Ethanol free gas and performance?

sherob

Old Herder of cats.
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Brighton, CO USA
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I know my Camaro loved to drink the 91 real stuff, so did the C14... throttle response was much better. :thumb:
 

Sadlsor

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I get the gist of these comments, including minimizing variables (wind, terrain, average speed, fill point, etc).
Also makes sense to me, that a carbureted antique, ...er, I mean the ST1100 would behave differently than a fuel-injected 1300. To some extent, at least.
I can get pretty consistent with fill level, speed, and terrain although not perfectly. In any case, I'm not going to over-analyze this, and yes of course there will be (IIRC) about a little over a dollar per gallon difference in cost. And then there's the blending... if you're mixing pure gas with xx gallons left over in the tank at fillup.
It comes down to wondering if I can up my 42mpg in all-around riding to closer to 50mpg with non-additive fuel.
At my hypothetical figures, it will still only net me approximately 50 - 60 more miles per tank so a best-case scenario still barely covers the increase in cost.
And as the Bucc-ees is about 30 miles from the house, there's over half a gallon one-way.
*sigh*
Thanks for the mental gymnastics. It was fun.
But still, in the end even with FI, I suspect the pure gas would benefit the engine internals like pump seals, fuel supply hoses, and such.
 
Joined
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It comes down to wondering if I can up my 42mpg in all-around riding to closer to 50mpg with non-additive fuel.
You can increase your mpg significantly by driving at 50 mph on a straight and level highway - in top gear, of course. That would probably top 50 mpg. Our '89 Honda Accord got over 32 mpg on the Cleveland to Toledo run many many years ago. The interstate is mostly flat and i drove 55 -60 the whole way. This only happened once on a mpg test run - start w/ full tank and fillup when I got off the interstate (no stop and go driving.) It was deadly boring.
 
OP
OP
ASPC
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Louisiana
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I'm not arguing your point, however, there is a difference between theory and practical application. We know eth has a lower energy content, and can easily calculate what the reduction in mileage, power, etc. might be for gasahol, but do the bikes know that and actually deliver 2% less power on 90/10 or are they unhappy to the point that they deliver 5% less power and mileage? Inquiring minds want to know.
And timing effects fuel economy..
 
Joined
Sep 5, 2023
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Has anyone noticed an increase in performance when using ethanol free premium fuel?
At the moment I haven’t used it enough to tell if it’s just in my head or not.
But its got me wondering how much ignition retard the ECM is using when running 10% ethanol.
My bike also runs just fine on regular gas with ethanol all due to the ECM.

The first thing I have noticed is an increase in fuel economy, which unlike perceived seat of the pants performance increases can be seen and measured.

The difference appears to be significant.
CBDDEA20-7D9F-49AF-8613-ECD6AF952A4F.jpeg


Just getting my ST1300 ready to sleep and have problems from living at 5000 feet elevation with many rides to 8500. Lucky my local station has non eth and 91 octanes. I still get some ping this high up the octane really matters. Something to consider when going over Mountains. If you know you're going up stay away from cheap gas.
 
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