It turns out that there are big differences between summer and winter blends. I looked into this because soon I'm about to head to my closest E-0% fuel supplier with jerry cans to have E-0% ready for my old carbureted bikes. But I'm going to wait until all Northwest refineries have done their swap over and delivered their summer blends to their gas stations.
 
 Essentially, winter fuel blends have a higher "Reid vapor pressure", RVP, meaning they evaporate more easily in winter to allow easier cold starting. Refineries use butane to achieve this, but butane has lower BTU.
However, summer blends have higher BTU, so they offer 3-10% better fuel economy.  Summer/winter blends differ based on geographic locations and historical temperatures, generally Pacific Northwest delivery summer blend gasolines have 2.5% more energy [BTU] capability than winter blends.
  Current 2024 summer blend delivery for purchase in the PNW no later than April 15.

Well, that may explain why my car indicates high 9s l/100km in the summer, but struggles to stay below 11 l/100km in the winter.

There are lots of things affecting gas mileage.  If you never check tire pressure it will be lower in the winter.  This means lower gas mileage.  Air is thicker....means more air resistance.  Ice and snow builds up on the vehicle...more air resistance. 

I've given up trying to find E0 gas.  I'll just do a carb and engine rebuild more often.  Maybe once every 10 years instead of once every 20.

  There is no  E0% gasoline easily available in Canada as of July 2023 thanks to the current federal government. Anyone who voted  for this current  ‘situation’  is responsible.  I live 12 miles from the USA where it is still available.

  I check tire pressure every 7 days. I run 42 psi.

  Air density is thicker in the winter. This causes extra wind resistance, but also higher air density  increases engine power. Drive from sea level at Kona on the big island Hawaii to Mona Kea  at  13,800 ft with invisible density, the rental car barely makes it.

  Ice and snow causes wind resistance. There are many instances in winter where there is no snow or ice on the vehicle, but fuel economy is still less.

In general I would say 42 psi is a bit high, but it depends on the tires to some degree.  I normally run around 32 to 35 on my truck.

Most folks idle their vehicles in the winter after starting, but don't do this in the summer.  This hits their gas mileage.  A good wheel alignment will also help gas mileage, but this applies year round.

  I’ve run 40-42psi in my tires since I was 16. My last set of tires on my truck lasted 175,000 kms.

On my truck I run the tires at the spec pressure.  Can’t remember what it is off hand.  My tires are wearing like iron.  They are ok I guess for grip in the dry, but absolutely SH*T when there’s even a tiny bit of moisture on the road.  Slip and slide like on snot.  I can drift corners at will.  Just pray I don’t have to make any emergency manoeuvres.

I’d gladly give up some wear for better grip.  And that applies to both my summer and winter tires.  In the fall I intend to get some better snowflake tires that I’ll run all year round.  I only put on 5-10K km per year.   

Running higher pressures may give you a tiny bit of extra fuel economy but it would be very incremental and would (to my mind) reduce overall grip.  I’d rather give up a tiny bit of gasoline for better overall performance. 

  Regardless of what tire ‘type’ you use , you gain .2%  increase in MPG for every 1 psi tire pressure. Different tire types have different levels of rolling resistance, but that ratio remains the same regardless of tire type. One may mock .2%, I do not considering the city of Vancouver has the highest gasoline prices in North America, specifically because of taxes. Yes, Inuvik probably has higher gas prices, I’m saying a place where there isn’t a 2000 mile delivery by truck for fuel.

 My 0% ethanol fuel source will confirm summer fuel delivery on Monday. Their refinery is in Western Minnesota using Alberta oil.

  March 1st, it's confirmed that ethanol free summer blend gasoline is now available at all stations in WA State Whatcom County.

Ethanol free is available at my local Home Depot  store (Victoria) - in the lawnmower/garden tool section, comes in a 3 litre tin, for a mere $28 plus tax!  Says that it is 92 Octane and has 'preservative' in it.

   Aspen fuel.

 

  I understand many will be thinking that I go on and on over meaningless stuff, in this case the corn ethanol mandated in this restriction saddled country. But,,,,,,,,,

I carry my ethanol testing  kit with me to fuel stations. Monday I wanted to clarify a rumour of certain fuels currently 0% ethanol available as a summer blend . I can confirm today, June 1st, co-op 91, and Canco 91 are currently zero ethanol. For lawn care equipment, motorbike storage, etc, I cannot underestimate the situation. My 1991 BMW, my 1981 Laverda, my 1989 Honda RC30 and my 1982 Honda lawn mower carbs have NOT been rebuilt.

I have a 4,000 watt gas generator on my RV.  Last year I couldn't start it and I tried to take the carb off to clean it but I gave up without fixing anything.  Last week I brought the RV into a mechanic who had to pull the entire unit off in order to get the carb off.  It was completely plugged with dark green sludge...so bad that the choke butterfly would not move and the float valve was stuck shut.  You couldn't even see the jets because they were plugged and covered.  This is the result of about 12 years of using ethanol in fuel and of course not adding stabilizer for winter storage. 

I had to order a new carb for the engine.  It's scheduled to arrive June 4, and then I can re-assemble the engine and re-install it on the RV.  It's going to cost me about a grand overall, thanks to ethanol.

  My abhorrence for corn ethanol started back in 2002, when my Moto Guzzi V11 Sport fuel tank expanded one full inch over a winter with 10% ethanol in it., after a late summer tour of NW USA.  Research later found a multitude of issues covering many machines.

I've made a habit of using Top grade Premium gas, usually from Chevron, along with Stabilizer when I put the bike(s) away at the end of the season.  I run the tank until almost empty, then top up with the Premium and stable.  ALWAYS start and run until very warm around Xmas/New Years to let the older gas burn off and be replaced by the stabilized fuel in the tank. So far, (knock on wood) never had any issues getting going again in the spring, even with my carbureted machines.

I've used a stabilizer in the final tank of the season on my bikes but with the RV (220 liter tank) it's an expensive proposition.  But from now on.....

   June 25/2024, Otter Co-op 91 , 0% ethanol

July 9/24, still 0% ethanol  91 at Otter Co-op.

All Domo Gas stations in BC as of July 17,24. are ethanol free on their 91, on independent nozzle, and are advertising ethanol free.

If ethanol was mandated by government to be in all gasoline how do some fly under the radar. Domo/Co-op ? Totally happy it's available and hope to find some around Kamloops.

   I have to assume that the small gas suppliers must be having trouble sourcing ethanol, by contract because of their minimal influence compared to the mega size retail competition.

   I should re-emphasize that for those who don't care about the 10% ethanol mandate, please know that I understand, but that there are certain fuel systems including nylon fuel tanks that don't do well with ethanol.

I run regular fuel all the time, except the the last tank or two prior to storage. I would then add quality stabilizer for storage.

Something I wonder about is why some gas retailers bother.  If the gubmint mandates 10% ethanol, what’s in it for retailers to source and sell it.  Why would suppliers bother for such a small overall market.  Of all the drivers out there, there is a relatively small percentage that are willing to search out and drive a greater distance to get it.

   Very good questions Ross. 

I tried reading this but my head exploded.

https://www.bclaws.gov.bc.ca/civix/document/id/complete/statreg/22021#part3

Huh?

  I tried reading it. I’ve never voted for the utter heathens that invented this clean fuel standard or carbon tax requirement, so am not versed in that particular language.