Any one else notice gas mileage has decreased significantly?

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SurvivorGuy

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I'm a gauge hawk and watch my gas mileage closely. I first noticed a difference a few weeks back on my FJR. I had just filled up with 91 with tecron as I always run the best petro in the FJR. Shortly after starting a ride on the highway, I noticed I had gone through 1/8 of a tank immediately! I kept a close eye and before I knew it, a 1/4 tank was gone. It was drinking gas at such an alarming rate, I thought I might have a fuel leak so I pulled over and inspected the bike. Nothing was out of sorts.

Then last week, I stopped by Costco to fill up and notice signs of 20% ethanol, which I do not ever recall seeing, so I did not fill up there and went elsewhere for gas. Wondering if the oil industry is cutting the petrol with ethanol across the board and not telling consumers.
 
FWIW, "Premium" fuel offers no advantage over regular for an FJR. Won't hurt anything but it doesn't improve performance or engine longevity in any way... (Different for an engine with higher compression that requires it to prevent knock.) I use high octane ONLY for the last two tanks of the season and only because where I live, "Premium" does not contain any ethanol - my preference for longer term storage.

Yamaha doesn't recommend anything higher than 10% ethanol so if you are getting 20%, that could be bad news. As far as I know, retailers aren't allowed to sell higher ethanol content without disclosing that to the customer. In northern regions, gasoline formulation is different in the winter from in the summer. The winter blend contains more volatile components to make starting easier (especially for carburetted engines) but fuel economy suffers. I wouldn't expect that a northern winter blend fuel is being sold where you are.

I would keep an eye on it. I have sometimes "filled" the tank and noticed the first gauge segment disappearing faster than expected. I attribute it to not getting the tank as full as I thought. Did you set the fuel mileage gauge when you filled?
 
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Then last week, I stopped by Costco to fill up and notice signs of 20% ethanol, which I do not ever recall seeing,
20%? I'd like to see a photo of that sign, please. I'm aware there is discussion and some debate on it, but pretty sure it would be newsworthy that some place has adopted that for their regular fuel supply. As noted, many modern vehicle fuel systems are not designed for the higher ratio.
 
20%? I'd like to see a photo of that sign, please. I'm aware there is discussion and some debate on it, but pretty sure it would be newsworthy that some place has adopted that for their regular fuel supply. As noted, many modern vehicle fuel systems are not designed for the higher ratio.
I stand corrected, the sign says 10% ethanol. I spoke with a representative at the Costco gas station who explained it is law in Maricopa County AZ that all gas stations use at least 10% ethanol blend.
 
FWIW, "Premium" fuel offers no advantage over regular for an FJR. Won't hurt anything but it doesn't improve performance or engine longevity in any way... (Different for an engine with higher compression that requires it to prevent knock.) I use high octane ONLY for the last two tanks of the season and only because where I live, "Premium" does not contain any ethanol - my preference for longer term storage.

Yamaha doesn't recommend anything higher than 10% ethanol so if you are getting 20%, that could be bad news. As far as I know, retailers aren't allowed to sell higher ethanol content without disclosing that to the customer. In northern regions, gasoline formulation is different in the winter from in the summer. The winter blend contains more volatile components to make starting easier (especially for carburetted engines) but fuel economy suffers. I wouldn't expect that a northern winter blend fuel is being sold where you are.

I would keep an eye on it. I have sometimes "filled" the tank and noticed the first gauge segment disappearing faster than expected. I attribute it to not getting the tank as full as I thought. Did you set the fuel mileage gauge when you filled?
Hi RossKean: I appreciate the heads up on Premium not being necessary. It appears that all petro here in A.Z. "by Law" AZ has 10% ethanol including premium. While I was in Idaho there were a few gas stations offering ethanol-free gas, but not here in A.Z.

in regards to the 1st gauge dropping quickly, I had filled the tank to the very top. Unfortunately, it appears gas prices have gone up and the quality down. Welcome to the new America!
 
in regards to the 1st gauge dropping quickly, I had filled the tank to the very top.
While I have experienced some tanks where the fuel disappeared faster than normal, it has been due to strong headwinds or an undisciplined right wrist. Reset your fuel MPG meter and keep an eye on it or calculate actual mileage for the next couple of fillups.
 
Unfortunately, it appears gas prices have gone up and the quality down.
Pure supposition. What basis in fact do you have that quality has changed? :cautious:

Hint: It hasn't changed. E10 has been over 90% of the fuel supply in the U.S. for well over a decade now, highly regulated and complex supply chain process.

That said, I would note the switch from winter-blend to summer-blend could be occurring now and there might be some slight changes in energy content (~+2% in summer gas) as compounds are shifted, but from what I remember Arizona (or some counties) is a boutique-fuel state and uses summer-blend year round.
 
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I stand corrected, the sign says 10% ethanol. I spoke with a representative at the Costco gas station who explained it is law in Maricopa County AZ that all gas stations use at least 10% ethanol blend.
Thank you on the clarification.

Actually, it's an Arizona law and not just the county. Arizona Revised Statute 3-3494
 
Pure supposition. What basis in fact do you have that quality has changed? :cautious:

Hint: It hasn't changed. E10 has been over 90% of the fuel supply in the U.S. for well over a decade now, highly regulated and complex supply chain process.

That said, I would note the switch from winter-blend to summer-blend could be occurring now and there might be some slight changes in energy content (~+2% in summer gas) as compounds are shifted, but from what I remember Arizona (or some counties) is a boutique-fuel state and uses summer-blend year round.

The knowledgeable gas attendant at Costco stated AZ requires a minimum of 10% ethanol which leaves the door wide open for a larger percentage of ethanol in the mix which would cause fewer miles per gallon. Call it supposition if you may but it's not just me who is seeing fewer miles per tank.

Say what you may, I say more $ at the pump for less quality petro,
 
Costco gasoline is Toptier rated (so that is good from the standpoint of keeping your engine clean), 10% ethanol will decrease your mileage by approximately 3% (over non-ethanol fuel; hardly noticeable), and as mentioned earlier regular is the preferred recommended fuel for your motorcycle. It has also been postulated that decreased fuel mileage can be attributed to the need to replace sparkplugs. I think you're off base in blaming the gasoline's quality.
 
Pure supposition. What basis in fact do you have that quality has changed? :cautious:

Hint: It hasn't changed. E10 has been over 90% of the fuel supply in the U.S. for well over a decade now, highly regulated and complex supply chain process.

That said, I would note the switch from winter-blend to summer-blend could be occurring now and there might be some slight changes in energy content (~+2% in summer gas) as compounds are shifted, but from what I remember Arizona (or some counties) is a boutique-fuel state and uses summer-blend year round.

UNLESS you are in a place that had both high summer temps AND under scrutiny for their air quality so run winter blends all year long. [That's a story about how to challenge Subaru Engineers in Japan on how to tune for the muy malo combo.]
 
UNLESS you are in a place that had both high summer temps AND under scrutiny for their air quality so run winter blends all year long.
It surprises me that they run winter blends in a hot summer. (Not saying that they don't) I don't know what it does to tailpipe emissions in terms of ozone/hydrocarbons/CO/NOx etc., but winter blends contain higher concentrations of volatiles and will contribute more to hydrocarbon emissions due to simple evaporation. Charcoal canister doesn't get it all and becomes saturated quickly. Greater likelihood of vapor lock as well.
 
I just completed a 2,500 mi trip from Seattle to Palm Springs and back (by car). I did the exact same trip last year. I did not notice any difference in mileage, so I would not say quality has changed on the west coast. Prices were higher this year, but who cares...
 
It surprises me that they run winter blends in a hot summer. (Not saying that they don't) I don't know what it does to tailpipe emissions in terms of ozone/hydrocarbons/CO/NOx etc., but winter blends contain higher concentrations of volatiles and will contribute more to hydrocarbon emissions due to simple evaporation. Charcoal canister doesn't get it all and becomes saturated quickly. Greater likelihood of vapor lock as well.

No canisters here either.
 
No canisters here either.
I was referring to charcoal canisters generally present in many vehicles including most cars - not specifically the California version of FJR. There are good reasons for NOT running winter blends in warm weather - not the least of which are volatile losses and fugitive hydrocarbon emissions. Vapor lock can be a real issue and problems with saturated charcoal canisters (on FJRs) are documented (even with regular fuel blends). Problems with fuel "boiling" in the tank are far more likely with winter fuels. (I seem to remember some cases of fuel "fountains" with Gen I bikes with hot engines parked in direct sunlight.)

As I mentioned, I don't know how the summer/winter blends affect CO/O3/HC/NOx emissions but raw hydrocarbons making it to the atmosphere will be higher for winter blends in warm weather.

Interesting side note - I bought by '07 slightly used from a guy in Connecticut (he bought it new from a local dealer). Despite its east coast origin, it was a California model and I experienced saturated canister related starting problems a couple of times (parked in direct sunlight on a hot day) before I elected to bypass the canister.
 
Phoenix is unique, we have challenges geographically that cause our emissions 'problems' to be higher than they should be. We're in a giant bowl, densely packed and high population.

That being said our emissions problems have gotten better over the years, and I'm not sure that we need emissions programs any longer. New cars are so clean that they are not the biggest problem.

enough soap box

We do have unique blends that are not shared w/ any other state/region summer or winter. We've had shortages here because of pipeline problems that caused us to ease fuel restrictions to get fuel from other areas.

I believe we went to year round ethanol a few years ago.

https://agriculture.az.gov/weights-measures/fueling/motor-fuel-quality/cleaner-burning-gasoline-cbg
 
Costco gasoline is Toptier rated (so that is good from the standpoint of keeping your engine clean), 10% ethanol will decrease your mileage by approximately 3% (over non-ethanol fuel; hardly noticeable), and as mentioned earlier regular is the preferred recommended fuel for your motorcycle. It has also been postulated that decreased fuel mileage can be attributed to the need to replace sparkplugs. I think you're off base in blaming the gasoline's quality.

I disagree with you and feel I am not off base.
 
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