So, I bought this 1975 CB750 last Monday.  Running when parked…15 years ago.  Rode hard and put away wet.  Lots of corrosion.  Oh well.  I paid but lots and lots of corrosion.  That’s the bad stuff.  

It’s complete and original.  23,000 miles.  Chrome is mostly pretty good and should buff up ok.  Tank is not bad inside, no dents.  Side covers are badly broken though.  Seat pan has/is turning to dust.  

I’ve been working on it quite a bit.  Carbs disassembled, cleaned, and reassembled with no new parts, fingers crossed.  It came with a K&N air filter.  Tore down the front end.  OMG!  Worse than I’d hoped (only to be expected though).  The brake bleed screw welded itself to the caliper body.  Fork seals are shot.  Fork tubes are really really shot.  Steering head bearings are shot.  Handle bar switch blocks are seized.  Every nut bolt and screw requires a Herculean effort to remove.  One spark plug was dead.  One spark plug cap was dead.  Electrics mostly don’t work.

The good stuff is.  The valve clearances were good.  Pouts look good (didn’t check gap or timing, assuming they’re ok).  Compression is 145, 130, 160, 150.  Bby Kawasaki is giving me a pretty good deal on Shinko tires so I ordered some in the event.  I’ve put together a parts list of stuff it needs.  So far it adds up to $1600.  I bought a battery for $70 and various chemicals for $100.  I’ve got a rough price of $1500ish for paint.  

I’m gonna do a colour change to Planet Blue.  There’s a reason for it.  I’ve been looking for a ‘75 CB750 candidate for about 15 years.  I had a ‘75 Planet Blue CB750 when I met my wife in 1977.  So it’s gonna be blue.  

What’s the best way to remove this bearing race?

Cut it with a cutting wheel on a grinder, reeeealy carefully, part way thru.

Take some good piccies of the switches and I'll see what I've got.   Driving to Chilliwack on Tuesday, maybe we can meet...I can bring the box of switches.

Might have some nice turn signals, too.

How fortuitous.  Roy, Bob, and I are heading out to Chilliwack in the morning to deliver a motorcycle.  Should be out there around 10:30-11:00.  I’ll try taking pics of the switch blocks, but they’re hanging off the bike.  And they’re a bit of a pain in the ass as the wires run inside the bars.

Switch blocks.

Watching with interest.  I've seen a few CB750's lately and am considering buying one to restore.  The only Z1's out there nowadays are restored and not cheap.

Hey Bill,

Nothin’s cheap.  You know very well how it goes.  So easy to sink a ton of $ into a motorcycle project.  Just have to go in eyes wide open.  This bike I have, I plan on keeping as a really nice rider.  Probably not anywhere near perfect.  I may not even take out the motor.  I may not even be able to get a collector plate.

The ‘75s are not all that much in demand, so not particularly valuable, except to me.  Off the top of my head, I see $7,000.  That may well be light.  For a bike that might fetch $5,000+.  But this bike will be with me for a while.  I reckon it’ll be good for when the Tracer900 becomes too much bike and I no longer feel the need to moto tour.

But man, I’m looking forward to getting this girl going.  Gotta come up with a moniker for her.

Man, I really like working on these carbs.  So simple, easy. 

  ‘75 small tank Honda 4’s are great bikes, you’ve got a keeper. 

Nice project, great to see wrench's being turned.

I have a box full of various "OLD" cables in good condition if you want good/old rather than buy new. Measure lengths., and show photos of the ends, and I might have some you need. Choke, Brakes lines, clutch, etc. A few of everything.  Yeah, I'm a Hoarder who hates to throw 'good' stuff out.

Ya, ok. Thanks Ron.  I’ll try and do that today.  Was thinking I might place an order today but maybe I’ll wait until next week.  Best to chew on it a bit longer.

So, I have the bike strapped onto the lift with the front end off.  I pushed it out into the lane and did a pressure wash.  I got soaked.  The bike looks much more appealing already.

Took the forks apart this morning.  OMG.  The thick, black, stinky stuff that was in there was so gross.  Eeww.

Ron,

Need both throttle cables.

Push cable: housing is 0.92m, cable is 0.98m.  On the left in the picture
Pull cable: housing is 0.925m, cable is 1.010.  On the right in the picture

Ron,

Speedo cable: housing 1.018, cable 1.047.  On the right
Clutch: housing 1.267, cable 1.358.  On the left

Ron,

Tach cable should be ok.

Use a Dremel with a cutting wheel to cut it part way through, then use a screwdriver or chisel to crack it open.

Double post.

Ya, I’ll try some variation on that.

Burnaby Kawasaki would have the correct puller for that race.  I had one but I broke it.

I'll try measuring the cables first opportunity. I'm tied up Sunday with the local Xmas Toy run, and show and shine, but will get to using my tape measure SAP. 

Bit of cleaning and polishing today. 
Cleaned the inside of the tank with muriatic acid water mix (1:3), then phosphoric acid.
Polished the front fender and fork legs.

  Those buffed up really nicely!!!

Very nice.

Chrome still in good condition.  No dings in the forks.  Someone gave that bike some love in the past.

I'm watching a 77 KZ1000 rebuild on KZRiders and it's amazing how filthy the bike is while being put back together.  Some people just don't give a damn.

My little 550 by comparison is looking decidedly scruffy. I've concentrated on the mechanical and only lightly on the cosmetic, so far. That alloy is looking fantastic.  Another gremlin cropped up during the TOY RUN so it's back on the lift in the shop;.  DRAT.
While I'm out there in the next few days, I'll rummage through my box of cables to see if I can help Ross.

One fork leg needed a fair amount of sanding where  most of the factory clear coat was gone.  The other had much of the clear coat still there, so I had to remove the clear coat then sand and buff.  

Much of this bike will remain dirty.  I’m not gonna scrub the engine fins and stuff like that.  But as I remove parts, I’ll clean and paint them before I reinstall them.  The fork tubes were absolutely shot.  Chrome was worn completely away for an inch and a half above the seals and above that they were destroyed by rust due to the fork gaiters.  So, of course, since they were dismantled, it just makes sense to to a reasonable job of cleaning.  

For now I’m just going to make a really good clean runner of it.  I’ve pared back on my initial list of parts and thing I’d like to do to it.  Things like chain and sprockets as they’ve been replaced sometime in the past.  Not gonna pull the engine unless it needs work. I can live with it for now.  Side covers, decals and paint will have to wait as they will cost around $2,200.  At least for now, a collector plate is out of reach.  For sure, a reproduction exhaust is not in the cards.  

I actually like the faded patina on the tank and side covers.  The side covers are badly broken, one had a piece from its centre fall off.  I’ve stuck them back together with crazy glue as best I could and will reinforce them on the back with mesh and epoxy.  If that fails then I’ll buy aftermarket side covers and leave them unpainted for now.  I’ll likely fork out for a Delkevic exhaust though.

In summary, I’ve had to dial back my vision and expectations for this bike, at least for now.  I had a “wind in the hair” vision of a pristine “wow” bike.  I haven’t the resources to do that.

And speaking of resources.  Ron, no worries about the cables.  I’d prefer to have OEM cables, but I had to order parts, so I ordered some aftermarket.  

Today I’ll probably tackle the steering bearing race and clean up the front wheel.

Fork tubes are shot.

Ross, nothing wrong with a good runner with patina.  At least it will be an honest bike.

   The story of the CB750 Honda.

https://www.youtube.com/watch?v=s6SzJsHOR9o

My BS side cover repair.  Drywall mesh and epoxy.

As clean as it’s gonna get by me until the day when I pull the motor.

One parts order from PartsNMore (Ontario) should arrive Monday.  Another order from Dave Silver Spares (Pennsylvania) might arrive end of next week but probably the week after.  It’s shipped via USPS and left yesterday. 

I leave on a motorcycle trip day after tomorrow.  Heading down the coast for four days (short days) then heading east and returning via the volcanoes. Eight day trip. 

But OMG, the exchange is f-ing brutal.  I went into the bank today to get $100USD cash.  It cost $140.13CDN. 

So, there was a small package of parts from PartsNMore waiting when I got back from my motorcycle trip to Oregon.  I installed new spark plug caps.  Now I have good resistance through both ignition coils.  New spark plugs.  A bit of effort to install the new roller steering head bearings.  Had to grind out the upper head stock and sand off the lower steering stem.  Oil filter & o-rings.  Signal flasher.  And a bunch of of other stuff that has to wait until I get my order from Dave Silver Spares.  

Interesting when you order stuff from Dave Silver.  Some stuff is in the US warehouse, and some stuff is in the UK.  They ship the stuff from the UK to the US then ship the whole package here via USPS for $20.  Waiting for things like fork tubes, fork seals, aftermarket seat, tire rim tape (couldn’t get it at Bby Kaw), grips, and more.

Picked up tires (Shinko) and tubes at Bby Kawasaki today.  Manny offered to let me bring my wheels and tires in and get help and advise in spooning them on myself, now that things are slowing down in the shop.  

Set the carb float levels (they were way off) and did a bench sync.  Put in new side cover grommets (side covers slip on and off like butter).  

Done lots of other little stuff.  Cleaning and rough painting of black bits like the chain guard and triple trees, front rotor centre.  Rough and dirty cosmetic work.  Much of it may well get redone if and when I really tear it down.  

Probably a bunch of other sty I don’t remember just now.  But it’s coming along nicely.  My order from Dave Silver will hopefully arrive late this week.  Might be ready for start up in a couple of weeks.

Dang!  Looks like the carbs have to come apart.

Figured I should check that the fuel tees were tee-ing and not leaking (I re-used the o-rings), and that the needles were needling.  Everything was going swimmingly.  Had the carbs clamped in the workmate with fuel source jury rigged.  When I went to drain the bowls, only #4 had fuel.  Took the bowls off and made sure the needles weren’t sticking.  Maybe they were.  Checked fuel flow with the bowls off and fuel flowed just fine.  Put the bowls back on.  No fuel in them.  Pretty sure the needles and floats are working fine.  Only thing I can think is that the vent passages are plugged.  I’ll take them apart again and vibrate in in the ultrasonic cleaner again.

Dang!

 Carbs, the new nemesis, with 10% ethanol our new reality.

Took the carbs off the rack.  Soaked each one in acetone for an hour, blew them out, vibrated them for another hour, rinsed, blew em out.  I’ll reassemble the rack tomorrow and try a gasoline test again.

It seems the needles are hanging up.  I’ve ordered new ones.

I had the same sort of carb issues when redoing my '81-550 Suzuki.  Carbs were a REAL mess.  After several attempts and hours of work, I ended up ordering a good used set from the Salvage yard in Williams Lake.  Good Guy, and very helpful. Prompt service too. Bike runs OK now.

  Getting back to my years old rant, regarding fuel/carburetor management,,,,,now with minimum 5% corn maise, …..,,
 I will tell you that use of good gasoline and very careful with our 4-5.5 month off season storage, my Laverda, and my BMW Airhead have not had their carbs rebuilt, 32 + yrs. They seem to run fine, no leaks.
 

Regarding needles and seats, best to order Honda ones. In my experience non-OEM have leaked. I clean up the seats with Brasso and a Q-tip. It cleans and polishes them up nicely. So far no leaks. Cliff.

I totally get what you’re saying about OEM needles and seats.  The problem I have isn’t that they’re leaking, although I have yet to determine that, it’s that they don’t seem to unseat once the bowls are installed. 

I got my aftermarket seat today.  When I went to put it on, I couldn’t find one of the hinges.  I’ve looked everywhere, it’s lost.  Hoping someone here has one, or maybe Bent Bike.  An aftermarket set costs over $50 plus shipping. 

Here’s a picture of it.

Are they rubber tipped needles and plastic seats or metal needles and metal seats.

If they're metal, you can use a little bit of valve lapping compound and lap the needle to the seat to remove whatever burr is making it hang up and make it seal better.

Gonna be a while till I can get back to the Honda.  My son, who lives in Vernon, broke his ankle on the weekend.  Surgery tomorrow.  He hasn’t anyone to help him out so I’m in Vernon for the duration.  So, he’s gimped and his cat is diabetic and needs food and insulin shots at prescribed times of the day. 

I was at a standstill with the Honda in any case.  Awaiting fork tubes, carb parts(needle and seats, carb holders and boots), help installing the front tire.  Then I can try and start it.  Then I’ll attack the rear half and electrics.

I suppose there’s an upside to being sequestered here in Vernon.  When I get back to the Big Smoke, there will be several packages of parts for the CB750.  I’ll have a couple of days work to do for sure.  Sitting here in my son’s basement suite, I really miss my shop and motorcycles.  Oh ya, I miss my wife too.

  Vernon has an extremely good tap room. Killing time is easy there,,,,,I had to work at the Fix Auto there back in 2018, nothing else to do there:

https://www.martenbrewpub.com/

I would need a designated driver.

Uber for the win. How far out of town does your son live?

Not out of town, but probably one of the highest elevation homes in Vernon, at the top of 43ave.

Up on the ridge, yeah that’s a long walk up.

Whoa!!  I know it’s never going to be pleasant when you start adding up costs.  Especially on old motorcycles.  I just totalled up what I’ve spent so far.  Dang online shopping, it’s just too easy. 

All in to date, I’m approaching $3800, including the three orders that should be waiting when I get home from Vernon.  That’s putting me on track for a complete cost of $6500-$7000 with new exhaust (Delkevic), paint & stripes, and a small contingency.  And all that assumes the motor stays in the bike. 

The things we do for love.

Oh, I know scary money to rejuvinate a bike.....a third of cost is shipping, and a big chunk replacing rubber parts.   Then sprockrets andf chain, a seat cover, and carb work, then tires......endless sieve.

Never do the math.

Yes, shipping is STUPID these days. And yes, don't do the math.

Ya, I know I won’t like it when I add up the cost.  And I haven’t in the past, except in a loose, in my head sort of way.  My finances now are much tighter than in the past and I’m quite a bit more concerned about my spending.  Plus I’m really curious with this bike to see where I end up in terms of value vs cost.

I was looking at kijiji last night, for CB750s just to see what’s out there.  Only the second time really that I’ve looked.  The first was when I was thinking about buying the one I have now.  There’s a few pretty good examples available, with stock exhaust, asking ~$6-7,000.  And not too far away, Calgary and one I think in Manitoba.  

In any case, I’ll have a pretty nice bike for under $7k.

I’ve been pretty good so far at avoiding some shipping costs.  Orders over $13 from some Canadian online sources have free shipping.  Dave Silver Spares is $20USD, but uses the postal service, so you get nailed by Canada Post for duties.  The US online sources charge a lot for shipping.  I think it’s a big additional source of revenue.  Sometimes you’ve no choice.  If that’s the only source for a certain part, then you have to bite the bullet and pay the shipping.  In future, for sure I’ll get my US sourced parts delivered to a US address.

Hopefully I’ll be able to come home in another week and I can get back to work on the bike.

So, I got home from Vernon this afternoon.  Managed to putter in the garage for bit.  Got the new fork tubes fitted.  Tomorrow, using the nice tire levers I borrowed from Steve, I’ll get the front tire on.  Then fit the wheel (I’ll worry about balancing later), the fender, and front brake.

Mike, the hinge you made for me fits really well.  Thanks again.  I’ll give it a coat of paint tomorrow.

So I got the front tire mounted no problem.  I installed the fender and wheel.  But when I went to assemble the brakes, I discovered that the supplier had sent the wrong lower brake hose.  I’m waiting to hear back from them.

So I got the rear tire off.  I actually just cut it off.  As with the front wheels, there is lots of really deep hard rust inside and lots of scars o the rims.

The big thing I did today is order an exhaust.  A 4 into 1 stainless megaphone from Delkevic.  $548.41CDN delivered to Point Roberts.  It shipped out today.

So the darned thing better run.

Lost of work done since I got home from Vernon.  Still awaiting needles and seats, and electrical connectors, but I think Canada Post has lost them.  Lower brake hose and exhaust will arrive next week.

Looks nice Ross,  I will have to pop by next week and see it.

Looking good Ross!

I’m pretty happy so far.  I’m at a bit of a standstill now until I get the needles and seats. 

Is it hard to get the carbs out for the needle and seat replacement ?

Old bikes are like having a lovely mistress.  Great to look at, but don't add up all the costs.

I installed the carbs ‘cause I wanted to see the effect of my efforts so far, even though I know they have to come out again.  I had no idea what a struggle they would be to line up the two airbox screws.  I think it “may” be that the aftermarket carb holders and boots are slightly different.  To answer your question, they’re easy to get out, but difficult to reinstall.  A second person would be helpful. 

The original holders and boot’s were as hard as rocks.  The oil of wintergreen/xylene bath had no effect.  They had to be replaced.

You're falling into a trap Ross.  The nicer you make it the more you need to do!

Try this with the carbs. Get a very thin piece of tin that will cover the air boots, bend a 90' along the length of it. That 90' bend will rest on the top of the air boots, make it say 3/4". I use a steel construction stud which is thin tin and cut off one of the 1 1/2" edges.

Put some lube on the tin face.
Rest it on the airboots.
Slide carbs into bottom of intake boots.
Lift back of carbs up and the bells should slide on the lubed face of the tin.
Slide the tin out and you should be pretty close..
Some heat with a hair dryer to soften the boots and remove any fasteners on the airbox might help with wiggle room....and good luck.....

I didn’t have much difficulty getting the carbs into the boots and holders.  The problem is that no two things can occupy the same space at the same time, or in this case, three things.  I can wiggle the carbs into the rubber bits easily enough, but then the airbox is pushed way aft and down from the mounting bracket holes. 

When next I need to do a final install, I’ll get some help to squish the bellows of the boots to line up the mounting bolt holes.  I imagine that the carbs will have to come on and of a few things before I’m finished. 

Do any of you guys know the initial setting of the air screws on the carbs for these older CB750s?  I currently have them turned out 1 turn from bottom.  Is that correct? At least as a starting point?

HAH........only FOUR CARBS?     Try fitting the rack of SIX from a CBX that has been sitting for a few years undisturbed.  It would make strong men weep.

Went to pick up my exhaust at Point Roberts today.  Had to pay PST, GST and duty.  All in, including gas, to get it home cost $635. 

  What’s the duty rate for vintage motorcycle parts?   CCS tariff code 9966 states that new or used  parts for vehicles 25 yrs old or older is duty free.

Looks like I was charged 10%.  Now, I didn’t press the fact that it was for an old motorcycle.  I don’t need to invite an issue with CBSA. 

So, my tally is now up to $4355.  The lower brake hose is scheduled to arrive Friday.  It seems Canada Post has most likely lost my needles and seats and electrical connectors.  When I finally get them (assuming that’s all the the carbs need), that $ will get me a good clean runner with lots of patina.

Having had it mostly dismantled (except the engine), there are still a number of things that need doing.  The wheel bearings seem fine, but to inspect them requires two special retaining ring tools to get at them.  I didn’t replace the chain and sprockets, as the ones on the bike are replacements that still look pretty good.  The fork ears are quite rusty if you look closely (and they are fairly pricey).  When I have it painted, I’ll have to get a stripe kit and lower tank mouldings.  The mounting nuts on the mirrors are really rusty, and to my mind, if I apply for collector plate, they would need replacement.  Stock Honda mirrors are still available, but also quite expensive.

For now though, I think I’ve done pretty much everything that’s required to make a cool runner.  Can’t wait to fire it up. 

I believe that's 'New', as in NOS, or used parts.

Well, ok then.  Next time I’ll try to get the parts duty free.  Thanks for the info Dave.

I just hope the border guard doesn’t take umbrage and send me in for a strip search.

  Don’t be afraid or intimidated coming back into your own country. This isn’t Venezuela,,,,,yet.

So, I started playing around with the exhaust to make sure it will fit.  Everything looks well designed and engineered.  Although it is fairly low slung. 

One of the spacer/sleeves for the fear mount at the foot peg is short.  It doesn’t account for the foot peg bracket itself.  So I have to sort that out.

After coffee with the guys, I went home and worked on installing the exhaust.  Delkevic 4 into 1 stainless.  Fits really well.  Just need a modified spacer/sleeve at the foot peg mount.

One more.

  Loos good Ross!

I installed the modified spacer/sleeve at the foot peg mount.  Fits perfectly.  So the exhaust install is complete.  Should get the lower brake hose tomorrow.  No idea when the needles/seats and electrical connectors will arrive.  I suspect that Canada Post has lost the package. 

Got the lower brake hose this afternoon.  Installed it and fitted it to the new calliper.  Pumped up the system no problem.  But….the brake sticks solid until I disassemble it.  Can’t figure it out.  Very frustrating. 

Gonna leave until tomorrow.  I’m off just now to see Colin James and his blues trio at the Massey Theatre.

Colin James in Massey Theatre was sooo good.  Nice small venue.  We had quite good seats. Seven rows up, centre isle.  Wasn’t too loud.  They played some older stuff, a number of songs from National Steel, and a couple of his latest album.  He’s starting on a new album in November.  They played two sets and, of course, an encore.  In the first set he played a different guitar on almost every song.

Slept on the CB750 front brake problem.  I think the problem is the pad on the inside.  I think the backing plate is too thick.  It’s not flat.  It has a weird convex bulge in the casting that I think is causing the problem.  I’ll do some checking, then maybe see if I can get someone to mill it down.

i had a similar problem with a honda pacific coast. the master cyl would not allow the fluid back in after releasing the lever. that tiny hole in the bottom was plugged. a fine sewing needle did the trick and now the brakes work great.

Ya. I unplugged the hole with a feeler wire.  But there may be multiple issues.  The caliper side pad is a tight fit and seems to bind.  This aftermarket caliper came with a domed cap that fits on the piston and the inside pad had a convex lense in the backing casting.  These things seem to make the thicknesses squeeze the rotor tight.  I dunno.  I’ve tried all manner of fitment combinations and can’t get it to work.  I think I need a second set of eyes and thoughts.  I’m not above asking for help.

Ok.  So I got it figured. 

I had bought an aftermarket calliper.  A complete unit including pads.  I thought it was a fair deal because the original one was toast.  Figured it would be plug and play.  NOT.

The inside pad was too thick overall because of the convex bulge in the backing plate.  I reckon it’s there so the pad can find its own seating square against the rotor.  Problem is, it pushes the pad up against the rotor too much by the same amount as the thickness of the convex lens.  It had to be milled off.  I used my hillbilly mill aka an angle grinder.  Problem one solved.  But it still would stick solid upon actuation of the brake lever.

After much removal and re installation, I determined that the calliper side pad was a bit too tight of a fit, and was binding.  So I used my hillbilly lathe, aka bench sander, to remove some material from its circumference. 

Front brake now works just fine.  But what a pain in the a## for something that was sold as being specifically for my bike.  I got it from Dave Silver Spares so I figured they would know what’s what.  NOT.

So now, it’s just the carbs I have to get finished.  I still have not received the needles and seats that were sent via Canada Post five weeks ago come Monday.  If they don’t arrive Monday they’ll mail another order.  You know, I’ve never really had a problem with Canada Post, even at Christmas time. 

I tried cleaning and polishing the seats with various products.  They’re bright and shiny but the needles still hang up for some reason. 

So, I cleaned the needles and seats…again.  Needles seemed to be dropping down.  Ok…I’ll give it a try. 

Installed the carbs.  It was waaay easier this time.  It would sorta fire.  Checked the carb drain screws.  #1-fuel.  #2-no fuel.  #3-no fuel.  #5-fuel.  Dang, what a PITA.

I’m getting impatient and frustrated.  All that’s left to do for now is the needles and seats, and front wheel balancing.  Unless, of course, I decide to do a full year-down.  Although I may also do paint in the spring if $ allows. 

When Canada Post works as it should, it works pretty well.  I got my replacement order this morning.  One week from Ontario.  Packages from the same place but sent via UPS, Purolator, or Canpar (they use them all) takes a week as well. 

Anyway, the needles and seats got installed right away.  Synch and float levels done on the bench.  Checked that there was fuel in all of the bowls.  Yup.  Installed the carbs in the bike.  Temporary fuel tank.  Choke.  Key on.  In neutral.  Pull in the clutch.  Press the starter button.  And WOO HOO, she fired right up.  Started to chug shortly.  Choke off.   Idled it down to 1000rpm.  Running smooth, great throttle response.  Oh oh, pushing some blue smoke.  Smoke coming up from the front of the engine.  Let it idle and come up to temperature.  All smoke goes away.  Ooo ya.  Look at the gauges.  Damn, the tach isn’t working.  Shut it off.  Disconnect tach cable.  Damn, it’s broken.  But man, I’m really stoked how well it started and runs.  And man, the Delkevic exhaust sounds great!

Couple things to do still.  My fuel line is a bit too big.  1/4”.  It’s what I had on hand but I really need a bit smaller line and clips.  Repair broken electrical connectors, now that I have them.  I’ll order a new tach cable at some point but I don’t really need it just now.  I’ll wait until I put together another order.

You never know.  I might show up at coffee on it sometime.

a couple of puzzling things.

The brake light doesn’t come on until the front brake lever is pulled hard almost to the bar.  Rear is fine. 
The rear park lights don’t work (neither of them), signals work fine. 

In both cases, could be a dirty switch......trak them apart and give them a good spray with conract cleaner and four ought steel wool, or something similar.....nail file?

   Is the brake light switch on the front a pressure type switch?

Yup.  It’s a pressure switch.  Anybody have a spare one kicking around that they don’t need?

Pretty sure the real park lighting problem is a wiring issue I need to track down. 

Glad things are perking up.  BUT, don't worry about a parking light.  You are SUPPOSED to be riding the bloody thing, NOT parking it.

Heh heh.  Ya, and if you ride fast enough, everyone else is too far behind to care about park/running lights.  Myself, I like to be as visible as possible.  It’s not urgent, or essential, but I will take the time to track it down and get the lights working.

I’ll try giving Bent Bike a call to se if they have a pressure switch and tach cable.  Then I have to try and track down some good quality thin wall 5mm (3/16”) fuel line and clips.

Here's one for about US$11 including free shipping to US.

https://www.cb750supply.com/products/5/honda-electrical/46/brake-switches (https://www.cb750supply.com/products/5/honda-electrical/46/brake-switches)

I called Bent Bike.  He said he’d look around and see if he has a switch and tach cable and get back to me today or tomorrow.  They also sell the nice flexible thin was fuel line and spring clips. 

After getting some extra eyes to look at the wiring diagram, we determined that the rear signal are just that.  Not park/ running lights.  The front signals are dual.

Started it again this afternoon.  Checked again to see if everything was working.  Had to replace the high beam indicator bulb in the dashboard.  Now everything works.  Except the front brake light pressure switch.  It works but only at high pressure.  Ordered a new one along with a tach cable. 

I was hoping the weather would clear enough this afternoon to run the bike up and down the lane a couple of times.  No luck.  Here are a couple of pictures of how she’ll look in the mid term.  Long term hopefully will see paint, new fork ears, exhaust collars, mirrors, etc, etc.

What a great thread! Thanks for posting all your hard work. I'm just at the start of another CB750K resto. I've started with a pretty good K6 but as usual the further I get into it the better I want to make it. Cheers, Cliff.

Thanks Cliff. 

So, after running the bike on the lift for a bit yesterday, I switched it off, stuffed all the wires back into the headlight bucket and reinstalled the headlight.  I got some appropriate 5mm fuel line today and hooked it all up.  The weather is heavy overcast but dry.  I backed it off the lift into the lane for a test.  Fuel tap on, choke on, key on, clutch lever in, press starter button.   Damn.  Motor turns but won’t fire!   What the hell?   I just had it running.  Damn.  Back on the lift.

Check it has fuel.  Yup.  Check it has spark.  Nope.  Tank off, check coil connections, okay.  Remove headlight.  Pull out the wires.  Yup, a black wire from the right switch block had come adrift.  Plug it back in.  Hook up temporary tank.  Fuel on, choke on, key on, pull in clutch lever, hit the start button.  VROOM. 

So I put it all back together, back it off the lift.  Run it up and down the lane once.  Front brake is not working well at all.  I have a master cylinder rebuild kit, brake light pressure switch, and tach cable ordered.  Might be here end of next week.

But hey, it runs. 

One note of concern though.  At idle, in neutral with the clutch lever out, the transmission rattles quite noticeably.  The noise mostly goes away when you pull in the clutch lever.  Is that normal for a CB 750?  Likely causes?  Should I be concerned? 

  Ah yes, the dreaded “Hy-Vo primary chain rattle , a well known character trait of sohc 750’s. Two massive chains without tensioners connecting engine to gearbox.
 The noise of the chains can be dramatically reduced by proper carb synchronization, and slightly higher idle.
  The fix is a case split, but will often return.

Ya, I reckoned it was the primary chain.  I’ve read there is a hydraulic tensioner, but over time requires a bit if rpm to get the pressure up.  I also read that an engine imbalanced by compression differential can also be a factor.

I’ve not yet done a vacuum synch, only on the bench. 

Certainly normal for later model CB750/900/1100Fs.  Telltale sign is that the rattle goes away when you pull in the clutch.  The rubber dampers in the clutch basket get hard and shrink, leading to the basket rattling.  The rubber dampers are not supposed to be replaceable, but they can in fact be replaced and kits are available from various sources.  Not sure if all that applies to your particular model though.  

This is what the basket looks like with the back cover removed, revealing the rubber dampers (which in this case appear to be new).

Thanks for that Dave.

But back to my front brake.  Now, I’ve ordered a master cylinder rebuild kit.  Scheduled to arrive next Thursday.  It’s really just a shot in the dark.  There’s probably nothing wrong with the old one.  I think I’m just rubbish at brakes.

The SOHC engines are generally noisy I find, at least with mine. A carb sync does help. There is a damper for the primary chains but nothing in the clutch basket like the DOHC's.
If you pull the pan you can measure the deflection of the chains to see if they are still in spec. This is described in the workshop manual. Cliff.

If you pull the pan you can measure the deflection of the chains to see if they are still in spec. This is described in the workshop manual. Cliff.
[/quote]

Whoa.  I’m not planning on getting into major mechanical stuff just yet, unless it’s absolutely necessary.  From the little I’ve read, it’s not seriously as yet.  Dang, I don’t even have a manual.  ☹️

Man, what a storm last night.  We’ve been in our house over 20 years.  Never had the power out as long, 5 hours.

Today, I opened up the doors and did a vacuum sync.  My bench sync was so close, it really wasn’t worth the effort.  I’ve never really been good at setting air mixture screws.  But once again the bench setting seemed pretty good.  One turn out from seated.  

Now, if only I could get the front brake sorted.  ☹️☹️

Really looking forward to getting her out and put her through her paces.

Up to +- $4522. 

The Delkevic exhaust sounds really good in the shop, but is fairly loud.

It adds up fast doesn't it?  Chain, sprockets, tires, brake parts, battery, maybe a new seat....

Ha, I didn’t even get new chain & sprockets!

 
  There’s some great stuff for your bike available from this place !!!

   https://www.charlies-place.com/

AAAGGHH!!!  I’m rubbish at brakes. 

So I got the brake light pressure switch and master cylinder kit today.  Installed them.  Put some fluid in the reservoir.  Pumped the lever a few times.  Some bubbles came up.  Then nothing….  No fluid at all is going into the system.  WTF!?

   Often it take an overnight sit to allow the air to contain in one spot for easier displacement. often tapping the master cylinder and rolling it around to release air out of corners,,,,,yes its frustrating. 

I've been known to crack the bleeder, fill the reservoir and walk away for a time.

I finally bought a mityvac.  They work.

+1 on the Mityvac.

Yup.  Did that overnight.  No joy.

I think I got something installed incorrectly.  Gonna take it apart.

If you can see the bottom of the reservoir, there is a little hole there that lets fluid into the mc. Check to be sure the holes are clear.

With older machinery, when in doubt, use a larger hammer.  Might not work, but tends to vent the frustration.

The holes were free from the get go.  Not frustrated enough yet to use a hammer.

The calliper was pooched so I replaced it with an aftermarket unit from Dave Silver Spares.  Replaced hoses I got from PartNMore/Vintage CB750.  I reasoned that the master cylinder was probably ok and decided to save money.  Then I realized the pressure switch needed replacing and it wouldn’t pump up firm with the new parts.  Ordered switch and master cylinder kit.  Got them yesterday but installed the master kit incorrectly.  Dismantled it and corrected it.  The new switch works better.  The system is filling now and I’m working on getting the air out.  It’s still soft.  I leave alone for a while and come back to it periodically.  Each time, I get a tiny bit more air out at the master.  I have the master tilted so that air cannot hide at the banjo.

I don’t seem to be getting any more air but the lever still seems soft.  I’ll give it overnight and check for air tomorrow.

So after all of that, the brake still seems soft.  I’m quite certain I have all of the air out of the system.  I’ll have to ride it to see if breaking is satisfactory.  At least the new break light switch works.

I've always found air trapped in two places:

  * At the corners of the banjo bolts - bolt bleeding can help with that.

  * In the Master cylinder bore.  With the bike on the side stand, setting the handlebars so that the rear of the reservoir is angled up as high as possible, pulling the clutch lever and let it snap back, helps pull bubbles back and out of the two MC ports - repeat until no bubbles comes out.

The banjos were tilted such that I doubt air would be trapped there.  I had the master well tilted so air couldn’t be trapped there either.  Dunno.  It must be in the calliper I guess.  My neighbour has a Mityvac that I can borrow.  I’m out of fluid though.  In any case, I can’t ride it until I get this sorted.  I rode up and down the lane a couple more times and it barely stops. 

At least having run it in the lane, I’ve determined that the gauges work.  Accuracy is yet to be determined.

I should have been clearer:  Bubbles are sticky little bastards and get trapped in the threaded holes at the 'shoulders'  of the banjo bolts.  At some point Honda, and others, started 'countersinking' the holes in the ends of the banjo bolts to reduce the cross-sectional area where bubbles can get trapped.  Loosening the bolts slightly while compressing the brakes allows the trapped air to be expelled, along with some fluid, past the threads.     The countersinking is evident in the attached picture of an aftermarket banjo bolt.

Those bubbles also stick in all the various corners inside a freshly filled master cylinder, and that's where the lever snapping can shake them loose.

Where’s a place locally where I can get some banjo bolts?

A quick google search shows mostly regular non countersunk bolts.

I dropped in to a Volkswagen dealership for my last purchase but they were very insistent I had to have a part number and they did not even know what a Banjo bolt was. First ones were wrong thread (1.25 vs 1.5 tip) then I figured it out and got and got another set. They were around $6-7 each.
Frank

Honestly, I have a hard time believing it’s banjo bolts.  They’re exactly the same as my Kawasakis.  Basically the exact same system.  I never had trouble like this with them.  I’ve bled this thing six ways from Sunday.  Pumped the calliper piston out a bit and pushed it back to bleed it.  I need a brake guru to give me some help.  

This morning I discovered a puddle of fuel under the bike.  Petcock is leaking.  Maybe just at the tank/rubber washer interface…I hope.  Took the opportunity though, to drain the tank and do some quantity measurements.  Once the fuel gets to the top of the petcock tube there’s 4.4 litres of reserve.  Then there’s still 1.5 litres remaining on the right hand side of the frame hump.  

I wouldn't replace them, I'd just 'bleed' at the banjo bole.  It can be a little messy, so you want to ensure paint is well protected. 

To be fair, brakes on 70's Hondas are pretty poor.

Maybe it's rotor / pad finish that's doing it.

Even the brakes on my Stelvio are awful until they've bedded in after a few miles.

No, Shawn, it’s the hydraulic system.  There’s just not enough pressure in it.  The lever is soft and goes all the way to the bar.  It’s not right.

I think the fuel leak was just that the petcock wasn’t tightened enough.

  It took me a month to bleed and evacuate the air from the rear system on my Laverda. Trapped bubbles in corners meant tape g with a rubber mallet, which did loosen bubbles which rose to the surface, but I ended up unbolting  it and rolling it around for a few minutes  each night after work. I still think I’ve got air trapped but  the brake works well.

Dunno what’s going on.  I think Apple changed things.  Can’t resize my photos anymore to post them. 

  I’ve consistently had problems putting pics on this forum. Gave up years ago.

When I started this thread it was quite easy.  When I chose the picture from my library, it asked me what size I wanted.  Now it doesn’t.  Won’t let me resize any which way I’ve tried.  They want me to use a third party app to do it. 

I too had to give up trying to send photos on the site in the past year or so.  I used to get at least 2 or 3 reasonably sized photos on an email, but no longer. Technology can be a total bitch at times.

Emailing photos to myself has always given me the chance to resize them. At least, this works in Windows. Select the photo(s) and right-click. Choose 'Send to email recipient'. A dialog box comes up with a whole list of sizes. I always use 600 x 800 - a good size for posting. When the email arrives (only takes a few seconds), I do a 'save as' in the original location and add an 'a' to the file name, so as not to lose the original.

Ya, we have Apples.  No Windows.

I’ve been looking on line for Honda seat stencils.  I’ve found two sizes.  5”x9/16” and 6”x 1”.  Which one is correct?  I think it’s the smaller one.

I still have the original cover I took off my 1976 and the Honda stamp is 9/16 tall by 5-1/16 long and the colour is light grey.
If you want it for reference just let me know.
James

Thanks, James.  Yes, at some point I’d like to see it.  I’ve heard of a couple of different paints for it.  Not sure which one would be more “correct”.  Krylon Fusion for plastic 42338 Nickel Shimmer, and Dupli-Color HVP105 White Color Coat.

I will bring it with me to Wednesday coffee.

I finally figured out that the aftermarket caliper I bought is sh*t.  There’s a machined grove in the base of the body where air is trapped.  
The pic is of the original caliper.  I managed to shrink it but can’t figure out how I did it to post a pic of the bad aftermarket caliper.

Ok.  The top pic is the original caliper the bottom one is the aftermarket caliper. 

I rebuilt the original one with David’s help except that where the bleed screw seats is so corroded that it won’t seal.  Lots of colourful language. 

  Aftermarket caliper??? Didn’t know there was such stuff out there.

Would anyone who has machining skills be able to help repair the bleeder screw seat?

I would need a lot more detail to be able to answer that question. Like any valve seat, there needs to be enough material on both sides to make a good match.

I tried to scrape out the crud.  With no success.  I may even have made it worse.

So I sent pictures to Dave Silver Spares along with my complaint/concerns about the caliper I got from them.  Their response was that it was fine, and basically that I don’t know what I’m doing.  They may be right, but  I’ve bled brakes many times before and never had this hard of a time. 

  English POME bastards!!!

I’m making a bit of progress on the front brake.  Now at least it pumps up with a few pulls on the lever.  But after a short time it’s squishy again.  Like I said…progress?

Ok, so you might need to borrow some tools for this but it's worked every time for me.
I learned about it while bleeding a Ford hydraulic clutch that had no bleeder screws. This is the way that Ford recommended bleeding the system.

Get a mityvac hand vacuum pump and a rubber stopper or some sort of cap that fits the master cylinder tightly and lets you connect the mityvac to the cap. You may have to make something. Mine is a rubber stopper with a piece of metal tubing in it.

Fill the system with brake fluid and leave a little space at the top. Put the cap on and connect the vacuum pump.

Pull vacuum on the system for about 30 seconds and release slowly. Repeat about a half dozen times and check to see if the system builds pressure.

I don't totally understand how it works but it has worked every time I've needed to use it. I think the vacuum helps the bubbles expand and work their way out of the system.

I've never had to use it on a motorcycle brake system but I can't see why it wouldn't work, or at least be worth trying.

So I asked Peter to see if he could clean up the bleader screw seat.  I didn’t really hold out much hope.  But he managed to do it.  Thanks very much Peter.  I’m 100% sure I have all of the air out of the system now, so rather than put the repaired caliper back on just now, I’ll run it’s is for a bit.  I hate brakes and brake fluid.

Ya, I think these brakes are just poor.  I’m 100% sure I have all of the air out of the system.  I’ve put a spacer in the lever to take up all of the space between the lever and the master cylinder piston.  The free play had been around 5/8”, now it’s about 1/16”.  The lever now, is firm and leaves room for fingers between the lever and the grip.  Still doesn’t stop the bike as quick as I’d like but it is what it is.  Maybe I’ve just gotten too used to the stopping power of my Tracer900.

A couple of days ago I took off the swing arm again.  When I initially took it off for cleaning and bushing replacement, I had inadvertently pressure washed out one of the felt dust washers.  Got some new ones in my latest parts orders, so I replaced them.  

Also in the parts order was a new rear wheel bearing retaining ring and removal tool.  In the past, the rear hub at the retaining ring has been punched so that the ring cannot back out on its own.  The bearings seem fine, but at the least I wanted to squooge in some new grease.  Had to use much force to begin the unscrew the retaining ring.  Immediately there was coils of aluminum coming off of the threads.  So I stopped and re-tightened it.  Leave well enough alone I guess until/if the bearings fail.  

The front wheel bearing retaining ring has been significantly damaged by a previous owner using a hammer and chisel/screwdriver, and punched several times.  I purchased a new ring and removal tool for this as well.  The front bearings feel fine as well, but I’d wanted to at least squooge in some new grease there as well.  But I’ll leave alone as well for now.

Sorry I didn’t get any pictures.  Would have helped explain things better.

Cheers,
Ross

My CB350 has the same ring holding the bearings on, by the time I got the front one off, I had to obtain another wheel, which was when I learned about respoking.

Regarding brakes, was wondering IF you had bothered to sand the pads.  If they are original, good chance they have hardened and "MAYBE" sanding them with coarse grit "MAY" allow them to grip better.  Just a thought as it has worked for me in the past.  I usually buff up New pads a bit as well before installing them.
Good Luck with the resurrection.

For the grease thing, you can buy an attachment for your grease gun that is a zerk nipple with a hypodermic needle on it.

Works great for balljoints, etc that don't have a zerk fitting. Just push it under the edge of the boot or even poke a hole and pump some grease in there.

Would probably work to go under the seals in the bearing too.

Ya, I scuffed the pads with course emery cloth.  Brake bits are all new top to bottom excepting the master cylinder body and switch splitter. 

Has anyone done back to back comparison between new rubber brake hoses and braided ones ?

I ask about braided lines because I’ve read read differing opinions as to whether or not they significantly improve braking.  Some people have said they improve braking significantly while others say that the difference from new rubber hoses is insignificant. 

over the years, "IF" I needed new brake hoses I would compare the price with stock versus braided. Can't say I've noticed a huge difference if pads are good and rubber hoses are in good shape.  On a race course there is probably a noticeable difference.

Go with the cost benefit.....either way, the hoses will possibly outlast you, and all of us, at this stage.

   Brake upgrades to my '74 Norton [SS Brake line and upgraded master cylinder] and BMW R100GS [SS braided brake line] have both vastly improved the braking capability as well as the 'feel'. Among th best money I've spent on these 2 bikes has involved SS brake line kit. 

So I’ve looked around a bit for braided brake lines to fit the CB750.  Sets are available that are reasonably priced.  Problem is that the reviews are not that good. Apparently some of them don’t fit all that well. 

Years ago I had some regular rubber lines made for one of my Kawasakis at Greenline Hose in Vancouver.  They did them while I waited and were only marginally more expensive than Z1 Enterprises.  I called them up today to see if they still did stuff like that.  The answer was no.  They’ve sold all of that equipment chain wide and no longer do it at all. The fellow suggested Gregg Distributors in Langley. 

So I called Gregg to see if they would make braided lines for me.  They would.  I asked for a ballpark price.  Anywhere from $50-$100 each.  So at some point, I’ll take in my old lines to see what it would cost and how long it would take.  The brakes on the CB750 need all the help they can get.

I have used "Russel" lines in the past. Buy the correct length and the banjo's that will work for you application. Harley dealers sometimes keep some Russel stock.

Not sure what you mean.  Do you buy the line cut to length and construct them yourself?

Russell lines come with AN fittings on each end. You buy the banjo from them and screw the line onto it.

Mopac will have Russel brake lines, i've bought them there before.

I used these guys for custom length, black Stainless Steel Braided lines for my Voyager: http://www.apexbrakes.com (http://www.apexbrakes.com)  Very competitive prices, quick turn around, and they're in Canada.

I have used HEL brake lines on several bikes, including my Wee Strom, '79 GS750, and '77 CB750.   Work fine, fit well.  Most bike shops can get them.  In all cases, I ordered rubber-covered SS braided lines, look OEM.

I just took a look at the HEL website.  Not a bad price $119.  I think I’ll see what the price would be from the local Gregg Distributors in Langley.  I’ll support local if at all possible.

Actually $119 +$4 for black heat shrink cover +$6.20 for tax, total $130 round number.  Seems shipping is included from Calgary.

Hey Dave,

I tried the link.  Looks like maybe they don’t exist anymore.

So I asked HEL about shipping cost.  $15+tax.  That brings the cost up to $150 round numbers.  When I get ‘round to it, I’ll check at Gregg Distributors in Langley.  If they’ll do it for that price I’ll get them there.  I’ll bring in the original lines, so should be a guaranteed fit. 

Ya, something weird with that link. Try this one: http://www.apexbrakes.com (http://www.apexbrakes.com)

https://www.charlies-place.com/shop/brake-line-kits/

https://www.charlies-place.com/product-tag/cb750/

It’s been a few weeks since I really even looked at the CB750. 

The last couple of times I had a pretty hard time getting it started.  Seemed ok once warm.  Haven’t had a chance yet to take it on the street.  Couple things I was lazy with when I did my initial checks.  The previous owner assured me it had been running when parked.  Ok, I guess. 

I had checked compression, acceptable.  I had checked the valve clearances, pretty much spot on.  I had looked at the points, they looked ok so I left it at that.  Today I thought I’d actually check the timing and points gaps.  Using a test light to check static timing, the timing on both sets of points was a couple degrees advanced so I put them spot on.  The points gaps were a bit tight, .010” vs .014” (.012”-.016” spec)so I adjusted them as well.  In order to make it easier to turn the motor with a wrench while making those adjustments, I had removed the spark plugs.  They were all black and sooty, so I cleaned them up before reinstalling them.  So she’s definitely running rich.

After our conversation at club coffee on Sunday I reckoned I’d do the Wired George coil mod to ensure 12v at the coils as power goes through the kill switch to get to the coils.  But I checked voltage at the coils first.  Whoa, 12.3 volts there, so no need to mess about with a modification. 

Gonna hold off on anything else until we get some riding weather, see if I can get the rich condition sorted. Well… maybe if I get bored I might attack the front brake again with braided lines.  We’ll see.

  An original 45+ year old coil I would automatically have skepticism.

  Regarding the desired color of choice, how many times have you flipped your lucky coin??

The coil is easy to check.  Measure ohms on the primary and secondary sides.  I don't know Hondas but for Kawasaki the numbers should be around 4 ohm primary and 15,000 ohm secondary. 

For the carbs, I would check choke plungers if the engine is running rich and float valves are correct.

Ya, not at all concerned about the coils.  Have good spark.  I was just bored not having done anything on the bike for a while.  I’d done the Wired George thing on all of my Kawasakis just because.  Never really noticed a difference. 

And the carb choke is actually a choke not a fuel enrichment.

Yeah, the WG coil voltage improvement isn't something you will immediately notice.  I've done it on my KZ1000, but not my Z1B.  Both bikes run just fine.  I converted the KZ1000 over to 4 ohm Dyna coils with a Dyna pickup.  The Z1B is the same but coils are original.

I suppose time can degrade the coils, but I have really strong spark.  There’s not even 23k miles on this bike. 

Colour choice?  Flipped a dozen times.  I was really stoked when I got this bike for sentimental reasons I guess.  As I said, I had one in Planet Blue when I met my wife in 1977.  I thought (hoped) she’d be enthused as well…not so much.  I asked her opinion about colour choose if/when I have it painted.  Planet Blue or Apricot Sparkle Red?  Well…she couldn’t give a sh*t. 

Gotta get her running well first.  The bike that is.  My wife works just fine.  I’m still leaning towards blue paint.  For the bike that is.  My wife’s colour is just fine.

As to the rich burning condition, I wonder if the float levels are a bit high.  I set them using the dry setting method as per Honda.  I wish I’d kept the clear tube tool for my Kawasakis.  I reckon it would fit the Honda  bowl drains as well. 

The coil mod may help more just on startup than anything.

The starter will pull a lot of power out of the whole system and if you've got any way to reduce the voltage drop to the coils while the starter is engaged it will probably make a difference.

That mod is very popular with the 750/900/1100F crowd.  I'm not a big fan as it just adds more points of failure and if there is a voltage/current problem, just cleaning the various contact points in the circuits fixes it.  Having said that, measuring more than 12V at the coil is a very good sign, but the current in the coils can still be reduced by dirty contacts which may not show up in a static voltage test.  As a test, you could just run a temporary jumper directly from the battery to the coil and see if the starting behaviour improves (if you wanted to get technical, you could measure the current at the coil with and without the jumper and if they're roughly the same, you're good, and if not, cleaning the various contacts will fix it).

I’m pretty confident the starting issue is carburetors.  With clean plugs it starts with like half a crank.  I might just pull the carbs off again and lower the floats a couple of mm.

I agree really with everything you’ve said about the coil power mod.  I was thinking about doing it just because.  But when I saw 12.3v at the coils, what’s the point?

I don't use the clear tube method any longer.  I just pull the carbs off the bike, drop the bowls and set the carbs on four glasses with the floats moving freely.  Then turn the fuel on and let the glasses fill until the float valve closes.  Then measure the distance from the bottom of the miniscus to the top of the glass.  I actually do it with two carbs at a time but you can do all four that way as well.

What the heck is a miniscus when it’s at home?

Meniscus is the curve in the upper surface of a liquid close to the surface of a container.   Most liquids have this tendancy, including water, and gasoline.

Meniscus is a cartilage in your knee.  That’s what google says.  Had to look in our hard copy of Websters Dictionary to see a definition.  

Four glasses of gasoline with a rack of carbs balance on top sounds like a disaster waiting to happen.  In any case, I’d have to make an assumption as to a correct level.  Don’t know if Kehein carbs would be the same as Mikunis. 

Can confirm - had to have part of a troubling one removed from my knee (lagging result of a particularly unskilled dirt bike landing) many years ago.    ;D

Looks like I can borrow a clear tube unit next week.  Assuming the Mikuni drain plugs are the same as Keihin. 

Honda says, with the carbs upside down, the distance from the carb body cutout to the top of the float should be 26mm.  I’ve done that.  From what I can glean from the interweb, this should coincide with a bit below the bowl gasket using the clear tube method.  Just like my Kawasakis.  I’ll check it. 

I have a box of blue nitrile gloves.  They last about a minute before gasoline destroys them.  Is there a better option?   

A meniscus is the curved liquid surface next to the container! ;D

https://www.google.com/search?q=water+miniscus&oq=water+miniscus&gs_lcrp=EgZjaHJvbWUyBggAEEUYOTIJCAEQABgKGIAEMgkIAhAAGAoYgAQyCQgDEAAYChiABDIJCAQQABgKGIAEMgkIBRAAGAoYgAQyCQgGEAAYChiABDIKCAcQABgKGBYYHjIKCAgQABgKGBYYHjIKCAkQABgKGBYYHtIBCTY4MzZqMGoxNagCALACAA&sourceid=chrome&ie=UTF-8

Ok.  So patience is not one of my virtues. 

I’d arranged to borrow clear tube tools from James at coffee on Wednesday.  Couldn’t wait that long.  We met for lunch today and I obtained two clear tube units.  Nice because you can do two at a time.  I checked the levels with the carbs in situ.  All were exactly the same level, about 1/4” below the carb body flange.  A bit lower than I’d have them on my old Kawasakis.  But I’ll leave them as is. 

When I drained the bowls, the gas was quite yellow/orange with a fair amount of water in the bottoms.  So I emptied the tank and replaced it with new clean gas.  Fired right up.  All I need now is some decent weather. 

I may go out to Greggs in Langley next week to get a price on braided brake lines. 

CB750 specs say the tank holds 18 lt.  I put 18 lt in my jerry can at the gas station.  That amount fills the tank exact right up to overflowing with the bike sitting level. 

So, I’m sitting in the garage feeling pleased with myself about carb levels and confirming the fuel tank capacity.  I like knowing that stuff.  Posting stuff on BCCMC threads.  Having a coffee.  

I start smelling a strong gasoline smell.  Damn, is the petcock leaking?  Is one of the carbs overflowing?  What the hell?

I go over to the bike.  No fuel on the lift.  No drips on the petcock.  But the top of the tank is all wet with gas.  Damn, I forgot the lessons I learned about a full gas tank above a hot engine.  

Glad you're having fun with your new toy Ross. I'm enjoying the updates.

OH YEAH.  A hot engine, and a full tank then take a break in the Cafe before heading out.  Guaranteed gas overflow.  It's happened to me a few times before I learned my lesson.

Hey Howard,

How was the fit of the HEL braided lines?  I’ve read that the sets that come from 4into1 in the States don’t fit on the fender clip. 

It's been a couple of years, but I don't recall any problem like that.   I'm always prepared to modify as required to make aftermarket bits fit and work properly.

Ok.  Thanks Howard.

Caught a break in the rain today.  Ran the CB up and down the lane 5or 6 times.  Starts and runs really well now.  Plugs look good.  I think the float levels are a bit low but I’ll leave them for now. 

I think having the timing and points gaps spot on likely helps.  But I really don’t understand why the gas that I drained out of the bowls was so skanky.  It really wasn’t all that old.  I’d cleaned, rinsed, and dried the tank really well.  Maybe not well enough. 

I’m really unhappy with the front brake.  Have to squeeze pretty much max to get it to stop.  I think my next step is to get braided lines and reinstall the stock caliper. 

Used GPS to check speedo.  Seems quite accurate up to 20mph.  Didn’t want to go much faster in the lane.  Too many kidz, kats, and cars backing out.  Some of my Zed speedos were way out of wack.

So I took my old brake lines out to Greggs to get a quote for black coated braided lines.  I want to support local, but the price is a bit high.  Their quote was $215.  I can get the HEL lines to my house for just under $150. 

Gonna try one thing at a time.  Cheapest, easiest, first.  I’d modified the brake pads to make them fit.  It was suggested at coffee one day (John) that that might be the issue.  I don’t think so, but maybe.  So I looked for another set of pads.  Everyone in Canada is out of stock for basic pads except Fortnine.  They have ceramic pads available with free shipping, so I ordered some.  Probably will take a couple of weeks to get here.  If they don’t help or if the improvement is minimal, then I’ll try braided lines with the original caliper (I know, that’s two things), then I’ll try a larger piston master cylinder. 

I always buy the softest organic brake pads I can find.

I don't care how long they last as long as they don't chew up the rotor and stop well.

The issue at the moment is one of supply.  Canadian suppliers that I can find are out of stock with no expected delivery date or backordered until end of March/April.  Except the ceramic ones from Fortnine. 

Oddly, the ceramic pads end up being cheaper than the less expensive organic ones.  The ceramic pads are $0.99 over the $49 free shipping threshold.

So I went back at the carbs again today.  Using the clear tube method, I set the fuel levels at 5mm below the gasket mating surface.  This turned out to be 23mm vs the 26mm spec when using the dry measuring method. 

Then I tried to fine tune the air screws.  Huh, no matter where I turned them, from seated to two turns out, I could discern no difference in engine idle speed.  So I put them back to spec setting, 1 turn out from seated. 

Starts and idles really well, good throttle response but smells rich.  Oh well, I can only do what I can do.  If it becomes an issue then I’ll get Rick from Burnaby Kawasaki to take a look at it for me. 

I’m thinking of putting some insurance on it tomorrow.  Just hoping I don’t have to stop too fast.  Projected delivery of my brake pads is February 15th

Regarding the air screws, almost sounds like they may have broken tips stuck in the ports.  Air screws have sharp tips when you remove?

If tips are lodged in the tiny orifice, I have had success using a short piece of nipped off sewing needle, to give a flat surface against the stuck point. Grip needle piece in needle nose vice grips, place on air screw tip, and tap vice grips lightly. With the stars alined, the tip should drop down into the float bowl area.

Hmm.  Interesting.  I’ll check them out Howard. 

Ya, I didn’t think so.  From what I remembered, the air screws were/are made with a flat tip.  And when I cleaned the carb bodies, I’m certain the ports were clean and I blew them out with my compressor. 

I do know that the pilot screws (as opposed to air screws) on my Kawasakis were long and pointy. 

In any case, I’m not going to worry about it too much just now.  I’ll wait and ride for a bit to assess.  I was thinking of putting insurance on it today.  As of Thursday, the long range forecast was sunny and dry for at least a week and a half.  Yesterday and today the forecast has changed dramatically.  Now it’s not so good.  So I reckon I’ll hold off a bit longer.

Yes, the air screws on Kawis are blunt and not prone to breaking but the fuel screws are very slender and sharp.  Do not over tighten.

Lately we are seeing high single digit temps here in Chase, but a fair amount of rain or fog.  Next week should be a bit cooler but sunny and low single digits.  The Goldwing is ready to go as soon as I see consistent double digits.

YOWZA, YOWZA, YOWZA!!!  I got it!  John, you were right!  My assumption that grinding of the pivot lense on the back of the wheel side pad wouldn’t matter was wrong!  Mia culpa.

I had ground it off because the dimensions didn’t work.  When bolted all together, the pad bound against the rotor.  I should have ground off some pad material instead.  Without the pivot lense, the wheel side pad never had full contact with the rotor resulting in diminished braking power.

I removed the pad.  I made a small domed button from a screw head and epoxied it onto the center of the back of the pad.  I sanded off some of the pad material so it would fit.  Reassembled it and today I tried it out in the lane.  WOO HOO!!

Not two finger braking by any stretch, but confident full force braking.  Scared myself a bit when it locked up and the front tire started to wash out.  WOO HOO!   Now I need a stretch of weather so I can insure and ride it.

When my new brake pads arrive that have the proper pivot lense on, I’ll switch out my jury rigged ones.  

Experimentation and innovation.  AWESOME

Definitely decided.  Definitely 100%.  Not changing my mind.  Gonna be Planet Blue.

"And this time, I mean it."

Ya but…the Flake Apricot Red is really sweet.

The past couple of days I’ve been reading some older posts on a SOHC forum.  Coming across some posts by Frank.  His passing has left a big hole in the community.

How soon we forget.  Granted my memory, for various reasons, isn’t very good.  What was Frank’s handle?

Doh!!  It just came to me.

Frank was a fascinating person.  I enjoyed his company when we met for coffee at the Ranch. 

Spent a day with him when I bought a parts bike from Roger Goldammer.

He was a character.

Got the “Honda” seat stencil today.  Applied and painted.  Because of the texture of the seat cover, the paint bled all around all of the letters.  I spent a bit of time covering it over with a black sharpie.  Just don’t look too closely.

There’s a ‘75 CB750 with  collector plate for sale in Chilliwack.  Looks in same or better shape than mine.  Been posted for 9 or 10 days.  Asking $4500.  Pretty good for a turnkey.  I’m up to $5500 and not even painted or collector plated. 

I used John’s timing light to check my static timing.  It was as near as dammit.  Confirms that static timing is quite effective when care is taken.

Have to bite the bullet and put in new float bowl gaskets.  I didn’t replace the original ones.  Probably really are the”original” ones.  They keep sluffing off debris.  I see it every time I drain the bowls.  I reckon the debris is getting sucked up.

I have the carbs off and blown out.  I’ll replace the gaskets before I fire it up again.

  I’ve decided purple is the best colour for your bike. Trevor would be in agreement I’m sure of it!!!

   :-)

Just for you, I’ll dye my hair to match.

I got some bowl gaskets from my friend who just bought a CB750.  It came with a bunch of spare parts.  Couldn’t sleep last night so I went out to the garage in the wee hours and installed them.  I’ll fire the bike up later this morning.

Should have fired it up then!

Your whole neighborhood could enjoy the Honda ownership experience.

 


 Don’t forget your new nose ring, and upside down cross tattoo on your Adam’s Apple.

So what are you up to in costs now?  And what's left to finish it?

Up to $5600.  Hopefully painting will come in at no more than $1500.  So round numbers $7100-$7500.  I’d initially hoped to come in under $7000.  Should be able to apply for collector plate. 

That's pretty good.  My Z1 resto cost $20k but it was in terrible condition when I got it.  Needed frame welding and a lot of parts to replace the non-stock ones.

I think your paint estimate is pretty good.

This CB750 project is no where near work you’ve done on your Z1. 

The big costs always seem to be chain, sprockets, tires, seat and paint.  I also did chrome, gauges and half the engine parts....cylinders, pistons & rings.  Oh...and a set of carbies.

Just because now I’m into CB750s, this is interesting.  It appears to be a completely untouched, low mile, ‘76 CB750.  I love the Antares Candy Red on the ‘76s. 

https://bringatrailer.com/listing/1976-honda-cb750-19/

That one looks nice!  Price is approaching KZ900.

There are a few on Facebook Marketplace.  Right now I'm cash poor, otherwise I might get serious.

17 quick bids, then stuck at $9K.  By the time it’s done and fees are paid, approaching $13,500 CDN.  Plus shipping etc, etc, etc. 

Sold for $9,100 USD.  Plus 5% commission = $9,555 = $13.377 (+-) CDN on your VISA card.

A very nice bike!  There is a 73 for sale on FB for around the same price.

I’m getting fed up with this thing.  I’ve had it firing on all four cylinders a time or two.  But #3 won’t fire now.  Has fuel.  Timing light shows it has spark. 

Today I took the rack of carbs off.  Cleaned the pilot jet, switched it to a different carb.  Blew out the #3 carb with my compressor.  Reinstall.  No joy.  WTF?  Next I’ll try switching the #2&3 spark plug wires.  When I feel like it, but not now.

Sounds much like the problems of old BRIT bikes. I was told by 'older' riders to push it over a cliff, then report it stolen.

  Internal combustion engines require compression. Fuel, and ignition. Regarding my own love/hate/love of my Norton Commando with original Amal Concentric carbs,  it was , after seemingly years of ‘bother’ that the upgrade to an easily sourced electronic ignition for the bike, whereby it’s become one of my most reliable engines in my busy little garage.  I’m not saying the specific issue with Ross’s Honda is carburetors, or electronics,  but I will say that old electronics have been the only component group that has left me at roadside with my old clunkers.   Carburetors generally have issues in their idle circuit, you can B.C. still get home on a main circuit,,,, I’m currently having issues with my  semi modern Honda XR650, after replacing all electric components, OEM and very cheap,,,,and Installing both Dynojet carb kits, and Dave’s Fix kits, it’s plainly a bad marriage of a CV carb and this engine.

I would think if fuel is getting to a couple of cylinders its probably getting to all of them.  But you could check plugs to see if they are wet.

My focus would probably be on the electrics.  Plug wires, coils and ignition. 

Run it and spray some carburetor cleaner into the throat of #3 while it's running.

If that cylinder lights off, it's a carburetor problem.

If not it's somewhere else.

Look for dead spark plugs. I've had them fire just fine out of the cylinder but when installed, under pressure they don't fire.

Are the valve clearances in spec?

It's just a big lawnmower engine, you can handle it.

It’s just the one cylinder, #3.  1,2,&4 are all hot.  Fuel in the bowl.  Timing light say’s there is spark.  That says the problem is in the carb.  But to be definite, this afternoon I’ll switch the 2&3 spark plug leads.  If it follows the wire, then it’s in the coil/wire.  If not, then it’s definitely in the carb.  

Compression is good.  Valve clearance is set.

I’ll take off the airbox and try spraying the carb cleaner before I tear apart the rack.

This bloody thing.  Aaaaggghhh. 

I came home after coffee and switched the 2&3 plug wires, no joy.  Switched plugs, no joy.  Re&re plug cap, no joy.  Checked resistance through the coils, both at 24 with 5ohm caps.  Drained bowls, turned on fuel & filled bowl.  #3 fired but not really hot but hotter than before when it was just plan cold. 

I dunno.  Could be an intermittent or inconsistent coil/electrical issue, or it could still be in the carb.

After all that.  I took the carbs off….again.  Pulled the float, fuel needle, and jets.  Sprayed carb cleaner in all the holes and blew it out with my compressor.  One more time.  Reinstall.  Start up, same same, warm but not as hot as the others. The whole time I’ve been using a laser thermometer so I can tell quite accurately individual exhaust temperatures. 

I’ve had the air screws set at stock, one turn out.  I’ve played with them before without any appreciable effect.  But I thought, what the hell, I’ll try again.  Turned the #3 screw in 3/4 turn.  Immediately audibly better.  Temperature came up right away.  Played around with it a bit and got it better.  They’re all still different temperatures, but at least they’re all HOT. 

Sounds like you might have a sticking float. If draining the fuel and refilling made a difference, it could have jostled the float into working properly. Can be maddening.

Fuel level will affect mixture so even if the screws are set the same, the fueling will be off if the float is hanging up and causing the level to be off.

Ya, I’ve been thinking about the float as well.  Gonna borrow James’s clear tube unit again and check periodically and see.

Sounds like electrics are operating as they should.

I've had floats in Mikunis stick along the side of the bowl if the float metal that joins them is bent even a tiny bit.  Don't know if your carbs are set up the same way.

So I played around with the #3 air screw and got it running much better.  Today I borrowed a clear tube tool from James again.  This afternoon I re-checked all of the float bowl levels.  #3 was a bit high so I adjusted the float tang.  I found it’s possible to do it without taking the rack of carbs off of the bike.  It’d be a bi*ch though if you didn’t have it up on a lift.

But man, she’s running really sweet, at least up on the lift. 

Have to wait until end of April to have enough $ for insurance. 

Patience, grasshopper.

Glad to see it's all coming together for you.

I’m sure hoping to get out to Saskatoon this summer, Shawn.  Not sure it’ll happen, but I’d like to visit my extended family, and you and Jen. 

We will likely be in Saskatoon in late August.  Then off to Semans to look for the grave of a lost great grandfather.

Keep us posted, we'll be sure to meet up with you somewhere.

Ok, so after a long long time at the body shop, I finally have the tank and side covers home.  The body shop is recommending that I hold off installing the tank trim, emblems and filler cap until next week.  There are several coats of clear on it and it’s a bit soft.  Don’t want to risk imprints from fingers or cloth.  I’ll have to turn the tank upside down on my bench to install the lower edge trim. 

I’ve gone with Planet Blue Metallic, and it’s really, really nice.

Couldn’t wait until next week.  I put the emblems, lower edge trim, and filler cap on this morning.  Turned out pretty ok.  Had to ream out the badge mount holes and filler cap bracket holes to remove excess paint.  Also had to scrape off a pit of paint from the inside of the filler cap brackets.  A bit too much paint buildup to all the filler cap to slip inside the bracket. 

But all good now.  I put in some fuel and now I’ll wait until the showers let let up later this afternoon to try it out around the neighbourhood.  It’ll be the first ride really.  So far I’ve only run it up and down the lane a few times. 

Fingers crossed. 

Sounds like almost a photo opportunity coming up, Ross.....

I’d love to post pics.  But I can’t seem to figure out how to do it on this forum anymore.

Took the Honda out for a toodle around the neighbourhood.  Runs well.  LOUD.  Had to readjust the clutch cable down at the bottom.

Starts and idles down nicely.  I reckon it's running lean.  Lots of popping on deceleration.

But man, is she beautiful.

  Richen it up 10%, the amount of ethanol you are probably running.  True fact.

I have the mixture screws set as per stock at one turn out.  I’ll try a 1/8 turn in and see.  Weather is crap for a while though.

Took the Honda to my son’s house in PoCo this morning to watch the MotoGP.  Man, what a race!!  Marc Márquez is the man!!

The Honda ran a treat.  Had it up to 60mph, or so the speedo said.  It felt like it.  I reckon I’ll be riding it to coffee on Wednesday.

  I’ve followed Moto GP for decades, even riding to Laguna Seca for at least 10 occasions from early 2 stroke 500’s to the Rossi days of power.
 Marques does appear more at home on the Ducati after a career on Honda. Good to see.

So I’m getting quite a bit of white, milky foamy stuff on the underside of the oil filler/dip stick.  I know this indicates water in the crankcase.  What could be the cause?   What might be a remedy?

The bike sat for many, many years.  I drained the oil, new oil and filter.  Could it be residual moisture from its long sleep?   It was very probably put away wet and forgotten. 

This afternoon, after riding to coffee I pulled the plugs.  #1&2 looked a bit rich, #3&4 looked a bit lean.  Turned the air screws out 1/8 turn on 1&2 and in 1/8 turn in on 3&4.  Try it again tomorrow maybe.

  The whitish buildup around the dipstick is a clear sign of the engine, and the oil, not getting up to temperature enough to evaporate the residual moisture buildup from multiple short trip runs. The machine needs to spend minimum 1/2 hr out on the highway, it will quickly disappear.

Ya, that’s what I’m hoping.  Thanks Steve.  BTW, after a couple martinis I posted a song.

  Two martinis!!!  I need 4 before I do that.  But only one to check them out.

A few bourbons and I posted the others.

Thinking of getting a Memphis Shades Classic Deuce windscreen for the CB750.  You forget how much grit hits your face when you’ve been riding behind a windscreen for years.  Had the Classic Deuce on my Kawasakis.  Not ideal in terms of aesthetics, but effective. 

I've ridden with a windscreen of some sort on all my bikes after I was riding my Brand '68 New Honda 450 on the freeway, from Chilliwack to Burnaby.  Intercepted a BEE or WASP heading in the same direction. SPLAT, right in my bare neck. Swelled up like I had a GOITER. Took a few hours, lots of wet cloths and a few aspirins to take the swelling down enough to feel up to riding back home to Chilliwack. Lessons hard learned, are well learned.

Check out these folks for a screen:  http://www.direction2.com/wsm.htm

Canadian, at least, been in business for a long time, good selection.

Thanks Howard.  The one from D2 that I might be interested in is the A33.  But I think it’s a bit bigger than I’d like, and I’m not enamoured of their mounting system. 

I am going to try and post a picture of Ross's bike

Okay Ross and his bike seem to have got wider after I took the picture

Ross and Steve you can thank me later for the body enhancements in the pictures!

4’  tall does not suit my double chin! 

Nice work Ross!  That paint really makes the bike stick out.

Yes, very nice !

Here's a photo Ross sent me.

Love to see those "Classic" brought back to life.  Good on You !!!

Well, at least you were able to post pictures….of a sort.  Thanks John.

Look'n good Ross.

Howard, how did you do that? 

Additional Options / Attach:

Yes Dave, I know that part.  But I can’t seem to be able to reduce the file size.  My apple products won’t let me do that.

Ahhh.  If you open the picture on your Apple, then take screenshot of the pix (and crop if necessary) and save, the file size should be quite a bit smaller (assuming file size is your issue?).

Tried that.

Firstly, I save my photos on my computer, as it is easier to access one of many photo resizers on the net.   Then just load which photo you want resized from your photo directory on your computer into the chosen resizer, and save in the photo directory with a new name indicating it is resized to 250kb.

Ahh.  So you use a third party app?

Try this.

Oh man. Don’t ask me to repeat the effort.  Not happy with it anyway. 

Looking great Ross! Well done!

So, yesterday I took the CB750 out for its first real shakedown ride.  Roy and I rode out to Agassiz.  There was a fellow out there who was selling a Dyna electronic ignition for $35.  I reckoned if it’s in working order, that’s a pretty good deal.  In any case it was a good reason to get my ass out for a ride. 

We headed out on the freeway.  I wanted to run it at speed and temperature to burn off the moisture that has been in the crankcase since I started it.  The bike ran well, as I expected.  An issue that’s become very apparent is the amount of effort it takes to turn the throttle.  It was an inordinate amount.  I’d only run it about 100 miles around town at this point.  I put it down to an overly strong carb return spring.  But as our ride progressed, the wrist twisting effort became greater, and the throttle seemed to catch and bind upon input.  Hmmm.

So this evening I pulled the tank and disconnected the throttle cables.  The return spring seemed absolutely fine when actuated be hand.  Hmmm.  The pull cable seemed a bit catchy though.  I opened up the right hand switch block to access the throttle grip tube.  Disconnected and inspected the cables there.  Really odd.  On the pull cable, the inner sheath had been pulled up and was wrapping along with the cable around the throttle tube.  Apparently, somehow the sheath has been pulled from inside the cable housing.  I pushed the inner sheath back down out of the way and applied some 3in1 oil.  Reconnected the cables to the carbs.  Feels great.  Now, if the issue reoccurs, I’ll have to replace the cable.  Cheap Chinese sh*t. 

Another small issue I noticed was a catch when I applied the rear foot brake.  I found that I had the upper bolt of the brake torque arm installed the wrong way.  The threaded end was catching on the actuator rod.  I removed the bolt, flipped it around so the threaded end was the other way.  Clearance achieved. 

These operations were performed under the influence of wine with dinner and bourbon afterwards.  So I’ll not be testing my repairs this evening.  That’ll wait until the ride to coffee at the Fort tomorrow.

Ross, when I put a Dyna on my '77 CB750 some years ago, it was $180. I'd say you did well.

  50 year old cables tend to act like 50 year old cables.

These are new aftermarket cables.

My LeMans has a Dyna ignition, you'll love it.

Coils are a bit spendy if you need to replace them but well worth it in the long run.

Glad you're getting it sorted out.

Glad you're making progress on the old girl. I have a habit of lubing the various cables each spring, prior to the first ride. Worked well, so far.  Over the years I've accumulated a box full of good used cables, throttle, choke, etc.  Even have a number of Hydraulic Brake lines I've rescued. If anyone needs something like that contact me with details.  It will only cost you the mailing fee.

Ok.  So I’ve ridden the bike about 300 miles.  Today my grandson had a baseball game that I attended.  When I left my garage, cold engine, I noticed a slight shudder as I engaged the clutch.  Hmmm.  I stopped and started again. No issue, so I went to the game.  All seemed fine until I approached the parking lot.  Leaving a stop sign, a pretty significant shudder upon clutch engagement.  Damn.  On the way home it occurred again with an accompanying significant rattle, which could have been the engine complaining about it.  I’ve not felt this kind of shudder anytime in the past.

Should I just go ahead and replace the plates, discs, and springs?  Are the parts at Vintage CB750 good quality?  I guess I’ll need the special tool as well.

Please chime in.

Cheers

  Been a while since I replaced a wet multiplate clutch, a year ago. New gasket, 10mm socket, new friction plates and clutch discs, proper torque specs for the 7-9 bolts to torque it down. I’ve never replaced the springs.
 What viscosity of oil you running?

In all the clutches I've ever replaced (or had out for other maintenance reasons) over the years, not once have I ever found a single metal clutch plate out of OEM spec.  I've replaced the clutch diaphragm spring on both my Vulcans (those springs are a known weak point that lead to clutch slipping).  In both cases, even the fibre plates measured well within spec.

I've never had a fibre plate measure less than the spec.  And I've never had a steel plate appear warped.  But I've had a couple of cracked or broken fibre plates.  I've replaced the springs on several clutches but not the big springs on the inner hub.  I don't have the tools to change those.

Be sure the hub bearing or bushing is in good shape.

Ya, I laid awake much of last night with it going through my mind.   I actually am fairly certain it’s not the clutch.  It reminds very much of the KZ1000 LTD I did.  The dogs and slots on a couple of transmission gears were worn and it jumped out of gear under load. 

I posted on the SOHC forum.  It was suggested that there’s an Allen screw on the end of the shift barrel that holds on the gear shift side plate that has possibly come loose.  Have to pull off the left side transmission cover to check.  Requires having a new gasket on hand.  I’ll order one today.  I’ll see if they’re available at Honda.  I’m sure hoping I don’t have to split the cases. 

Left side transmission/shifter cover gasket ordered.  Hopefully it will be here end of next week.

So having the gasket on order, I decided to open up the transmission cover.  Mine is a #3 cross head not Allen head.  Tight as can be.  Dang.  Now I’m thinking the worst.  Splitting cases and sourcing transmissions/parts.

Having occasionally had similar situation arise, I was advised to push it over a cliff and declare it stolen.

That would be JIS crosshead?  I use impact screwdrivers if they are tight.

  I’m assuming you mean Ohillips head rather than cross head Ross?
  Your entire motorcycle is fastened together with JIS head screwdriver heads. I strongly suggest getting all 3 different sized heads at Princess  Auto. You may need to buy a multi head tip mini box.

   Vessel JIS screwdrivers are the best made .

Ya, it’s JIS. Thought I’d push some buttons. 

The screw was staked at the factory and you can see it hasn’t moved.  I thought it would be too good to be true.  So I’ll get the gasket and ride it a bit more maybe, to try a get a definitive diagnosis.  But I’m pretty sure I’m looking for a transmission or parts there of.

A trick from the Bevel Ducati guys that I found when I was trying to get the clutch in my 860 to stop slipping (it worked) .

Those clutch plates probably sat dry and stuck together for a long time.

Before spending a pile of money on transmission parts, I'd try pulling the clutch friction discs out and soaking them overnight in some ATF.

Transmission fluid has friction modifiers in it that are specifically for wet clutches. Engine oil doesn't have this and since it's a unit engine....

Won't cost much and beats tearing down the transmission.

  JASO MA and JASO MA2 rated engine oils both have specific additives for wet clutch operation, and longer chain molecules for gearbox operation.

  Ross, are you concerned that you may have a bent shifter fork?

Could be a bent shifter fork.  Most likely if a fork is bent, it’s because the dogs and ears are worn, then the gears slip apart and bend the fork.  One problem causing the other, I’m thinking.

 Splitting the cases should not be taken lightly!!

Shawn, the clutch has been working fine.  It’s possible that it is to blame.  That would be an easy fix.  It doesn’t slip so much as chunk and juddder, and not all the time.  When I get the transmission cover gasket, I’ll ride it some more.  It could well be the clutch.  That would be my hope, but I’ll do some research in the meantime.

Steve, splitting the cases is the last resort.  I’ll certainly exhaust all other options first.

Another check before splitting the cases....drop the oil pan to see if there are any metal bits in there.

The shift cover gasket will be here hopefully by the end of the week.  At least then I can ride it a bit more to see what’s going on.

In the meantime, since I’d have to order a clutch cover gasket just to access the clutch discs, I placed another order.  I ordered gasket, clutch removal tool, friction discs, springs, tab washer.  And some rubber parts for neighbour’s bike.  Should be here in a couple of weeks.

So I got parts today from VINTAGECB750 in Ontario.  I had to wait for the special tool to remove the centre nut. 

I dismantled the clutch and measured the discs and plates.  They were all right on original spec.   The inexpensive (cheap Chinese crap) friction discs are barely within spec thickness and the friction material is much narrower than the original.  So I cleaned and sanded the plates with 600 grit paper, cleaned and oiled the friction discs, and reassembled it all.  The I measured the springs, they were well within spec, but the new ones were a bit taller, so I put them in.  Only 300 miles on the oil but I changed it as well. 

I ran the bike up and down the lane and all seems well.  We’ll see how it goes over time.  I’m confident that the clutch is fine.

So, yesterday at our midweek coffee, someone asked me how much my paint cost.  Rumours floating around that I paid around $4,000.  Not so.  But…I did pay quite a bit.  Now, I can rationalize and justify, but what’s the point.  I still cringe at the outlay. 

The short answer is, I paid $1500.  That was just to apply the tank stripes and paint.  If I’m honest with myself, just sandblasting, stripes, paint itself, and paint shop cost me $2173.94.  I also had to buy new side covers as well as the originals weren’t really repairable, $116.17.  So total $2290.11 as it sits. 

Unbeknownst to me when I started the process, there are complete body kits available from Yamiya in Japan.  Unfortunately the Planet Blue sets are sold out, and have been since I first found out about them.  Totally worthwhile, and in hindsight, a route I should have taken.  Could have had it delivered to Point Roberts for just under $2,000.  I certainly could have recouped some of that cost by selling my original tank, the original side covers are worthless, I have them hanging on the wall in my garage for artwork.  The Yamaha kit does not include emblems, lower tank trim, or gas cap.  All of which I also bought. 

Other than the $300 difference in cost, I’m really pleased with the results.  And I know that at least I’ve retained the original fuel tank.  I put some $ into the local economy as well. 

So, no, I didn’t pay $4,000 for my paint. 

I had two sets of Z1B colours done by Michael in Surry for $2,500.  I supplied the paint but I don't remember how much I paid for it.  That was a few years ago..maybe 2016?  So overall your price is OK I think.

I took the CB750 over to the Island yesterday for a Celebration of Life.  Except for a GPS snafu, the bike ran flawlessly.  The clutch seems to be behaving itself so far.  Could well be that the plates were sticking.  I’ll keep you posted.

  GPS's act very odd when the motorbike is 40+ older than the GPS.

Bit of an update.  The CB750 is running really, really well.

I finally got around to getting a match for a modern paint.  Honda Planet Blue matches really close to Ford B3, Atlas Blue.

So, at coffee last Wednesday we were talking charging systems.  Mrs. Wheels is having issues with the charging on her ‘81 CB650C.  It brought to mind the system on my CB750. 

The system on my CB750 has a separate rectifier and regulator.  What I’ve found on the interweb is that my bike charges at 12.4v@2,000rpm, 13.2v@3,000rpm, and 14.5v@4,000rpm.  That jives with my own checks.  So essentially it’s not charging at idle.  Given that it’s charging as it should from the factory, and I’ve had zero starting issues, is there any advantage to installing a new integrated reg/rec unit?  ie, would it charge better at lower rpm?

IMO, I wouldn’t bother. While your charging system is easily considered archaic, so is the regulator/rectifier  heat sink system, compared to modern charging systems in the automotive industry going back 25 years.  Most older machines,,,,I’m assuming your Honda included , have an on/off headlight and running light handlebar switch,  which is there for a reason, during startup and low rpm warmup.
  I replaced the charging system on my Norton because it’s charging system  is even more archaic than yours, with heat sink zener diodes placed on the side Z plates, which works fine until one zener decides it does not want to perform EXACTLY the same resistance as its performances match  partner on the other side,  which then  makes one try to take more excess electricity than it’s able, which causes death of the diode, and then the other, followed by overheated battery and overheated stator. My current setup using a Podtronics  solid state universal reg/rec  3 phase unit has worked admirably for 25 years, releasing g an exact 13.8 volt maximum steadily, the unit capable of negative ground, positive ground . I probably should have bought one of these for the Laverda during my recent charging issues with it.

By all accounts, the axiom “if it ain’t broke, don’t fix it” applies here.  It seems that charging doesn’t change with installation of an aftermarket reg/rec unit.  So unless, and until, the original regulator/rectifier system fails, I’ll keep it as is.

There may be a screw on your regulator that allows you to vary the voltage a bit.  You could probably get a bit more at lower rpm's but it would then charge at too high a rate at higher revs.

So, the other day I had the left side cover off to poke around with the regulator/ rectifier.  I had a bit of trouble getting it off. I guess I didn’t get it pushed back on properly.  I lost it somewhere on the freeway on my way out to coffee in Ft. Langley yesterday.  Dang.  Oh well, replacement cover and emblems are ordered.  I still have enough pain left over to get the new one painted. 

I’m having shoulder surgery August 1st so probably won’t be riding the CB750 until spring, so today I began bedding her down for a few months.  I’m hoping to get do a run with the Tracer900 up to Sicamous Sunday, returning on the 31st.  I’ll try to leave Sicamous early enough that I can get home and bed down the Yamaha that evening prior to my surgery the next day. 

In any case, that’s pretty much it for my motorcycling for this year, most probably until spring. 

Think positive.  You have the CB-750 sitting, just waiting for you once you feel up to giving it more TLC.  The Yamaha should be good to go come spring if you put it away correctly.  Modern machines are pretty good that way.
Good luck with your surgery. I had similar done back in '08, and after about 6 months of rehab was back on a bike for short runs.

So I have replaced the side cover.  Cost me $300.

  I can’t stop thinking of a perfect side cover skittering down the highway,  then crunched by a gravel truck tire.

Ross:  Somewhere in my heaps of junk, I have a bag of glue on plastic 'plugs' with lanyards attached.  They're perfect as a back-up for securing side covers (that's why I bought them).   You're welcome to have some if I can find them. 

That would be great Dave.  Probably need just for the left side.  The right side can’t come off if the oil dip stick is in place.

Ok.  I’ll try to post a couple of my collector plate photos.

Woo Hoo!!  I did it.  It’s a bit of a process.  If only I’ll remember how to do it next time.

Looks very good!

Definitely has classic lines.

Yes, very nice Ross!  You did a great job!

Beautiful as always.

Good job Ross, well done.

Thanks guys.  Hopefully I’ll be able to ride by spring.

Always great to see a "CLASSIC" rejuvenated.  YA DUN GOOD !

VERY nice.

So last spring I bought a used Dyna ignition off Facebook from a guy out in Agassiz. 

Should have waited until my shoulder was a bit better to install it but I was so bored.  Hadn’t intended to do until the winter.  Anyway, I installed it last weekend only to discover it is NFG.  The 1/4 pickup is open all of the time.

So I ordered a brand new Dyna off Amazon.  Installed it today.  Static timed it.  Eazy Peazy.  Will do a fine tune when next I start it, and that won’t be for some time.  Will wait until my shoulder is well enough to go for a ride. 

  Ya, used electrics, unless free.

I have one brand new that I tried to give to 754 but we never managed to hook up before he died.  I still have it in my shop somewhere.  I was thinking of putting it on my KZ650 but I don't know if it would work.

If the plate fits, I think it should work.  Give it a try.

I thought I’d re-check the compression on the CB750 to see if it had changed any.  Whe I bought the bike, it had sat for at least 10 years.  I check compression with a borrowed gauge before I fired it up. 145,130,160,150.  I thought, hmm not bad.  But I wondered if it might change after running it for a while.

So I borrowed a gauge from John D.  A different gauge.  Put it on the #1 cylinder and cranked it over.  What?!!  Only 90psi!  WTF?   Then I realized I forgot wide open throttle.  DOH!!  Then 120,130,125,135.  Not sure what to think so I did them again with the same results.  Not sure what happened with my initial readings.  I didn’t recheck them at the time.  But I’m happy with the results I have now.  As good as, or better than any of the Zs I had other than the ones with rebored motors. 

Did you do the compression test cold?  Eengine should be warmed up first.  The Z1 manual says if you have 15 psi difference between any two cylinders you should investigate. 

What is the specification for standard compression ratio?  For a Z1 engine it's 8.5/1.   That means 8.5 times 14.5 or about 125 psi. 

I actually don’t remember if I did it cold the first time.  This time it was cold as I have the tank and carbs drained until I can ride again.

Warm vs cold is a good point.  But I’m ok with the latest values.

A little carbon in the compression chamber makes a big difference.

So today before the Grey Cup, my neighbour and I checked the compression on his ‘75 CB750.

His bike isn’t nearly as nice as mine, but someone put a lot of time and $ into it to make it a really good solid runner. 
We started it up and got it good and warm.  All cylinders are right at 150psi or slightly above. 

Thank John, for the use of your compression gauge.  Now I’m thinking that I may have to start my CB750 to warm it and re-check the compression.  But that may well have to wait until my shoulder is better than it is at the moment.

I complain quite a bit about it, but my shoulder is getting better.  Just not as quickly as I would like.  But today I’m feeling like I’ll be riding again at some point.  Can’t wait.  This year has been a real bust as far as motorcycling goes. 

  I hear ya Ross. This year was a total bust for me riding wise. Zero travel was the call from my neurologist, and I gotta follow his orders. Cancelled 2 events and managed to get my money back.
  Hopefully 2025!!!