question about mixing fuel

[renegade_xs11g]

My wife and I are heading north over Laborday weekend, planning about 1,000 miles our longest yet....

anyways to the fuel, I've bought about 3/4 of a gallon of racing gas '110' octane, I wonder how much I can mix per gallon and not go overboard....

the reason I ask is...I ran out of gas a couple of years ago and a really nice guy stopped and gave me some.
but he told me that I'd better get some gas to dilute the stuff, of course I asked the dumb question,

Well to make an even longer story......

he raced bikes, and I wound up nearly 15 mpg better and Wow what a diff in performance....

Can anyone clue me in on this????

[Crazcnuk]

Not sure what you are saying, but 100 Octane is as high as the octane scale goes.

Higher octane fuel burns slower and produces less power. If anything, if your motor is properly tuned, higher octane will give you less fuel economy.

However, if your engine requires high octane, so as not to knock, you can dial in more timing with the high octane fuel. this will give you more power and mileage on that type of motor.

The XS is better designed than mid 60's muscle car engines, though and has no use for the extra octane.

So, if you are saying you got 15mpg better on his cocktail, it wasn't due to the octane rating, it was either something else in the mix, or your bike is horribly out of tune.

[trbig]

Not sure what you are saying, but 100 Octane is as high as the octane scale goes.

There's a local station that racers use that has pumps for 100, 105, and 110 octane? I've always seen Sunoco pumps with a value listed over 100 octane.. usually 101-103??

Tod

[renegade_xs11g]

I gotta admit, it has been a couple of years,
but IIRC I had gotten somewhere around 50 MPG that next tank,

but, at the same time it's running A WHOLE LOT BETTER NOW than it was then, pu wire fix, mikesxs coils, and a few other things

[Crazcnuk]

http://en.wikipedia.org/wiki/Octane_rating

I stand corrected. It looks like they modified the Octane scale to add some more fuels over the 100 rating.

It also looks like most of the new higher octane fuels are alcohol blends?

[Ivan]

if it was racing fuel, it might have had a bit of nitromethane in the mix. I know they use it in some of the auto racing, not sure about bikes.

[HobbyMan]

It probably doesn't have ethanol in it. Many racing fuels still do not contain ethanol. Ethonal decreases your fuel economy. I have reaserched this before. Actually, burning slower can help your performance. (To a certain point) It can also decrease it. If it burn's slower, you get power as the piston continues to move. Its when the fuel is not completely combusted when it exits that you loose power. (It all depends on tuning and RPM ranges) Just octane alone will not give you that kind of increase (or much at all on our bikes). I would chock it up to ethanol. Ethanol has a lower btu rating than regular blended gasoline.

HORSEPOWER: Because Ethanol contains oxygen, it has a very low power stoichiometric when compared to gasoline fuels (6.5 compared to 12.5). Ethanol must be run at much richer mixtures than gasoline, more than offsetting the lower energy per unit volume.

from this site

[renegade_xs11g]

The brain works in mysterious ways!

Sometimes I can remember things in great detail....sometimes not.
Sometimes I can remember things in entirety....sometimes not.
Other times, well sometimes the fuzzy details become clearer as I think on it,

That is but 1 result of driving for a living, time to think

Think on this I did.....I can remember where I was, what he drove, and even some of our conversation...not much took all of 3 minutes to restart the bike
he said something about aviation fuel, but I can't remember if he told me any ratios, most folks I've met don't give recipes, just ingredients



Well, we're back from our trip, I start out mixin in a little bit of the 110proof
I wrote down miles, gallons, and mix rate.......
I didn't do the math, just did estimated mpg on the fly
BUT I did a consistent mix.....

I'll do the calculations and post them next weekend,
but, for now,
I'll say the results suprised me.............

We traveled from Jackson, Mi to Munising, Mi by way of White
Fish Bay, Mi and a stop off to see the Lower Tahqumenon Falls...I misspelled that didn't I???
then looped south and ran the North Coast of Lake Michigan back over the Macinaw Bridge at night, long before the Yearly BridgeWalk held ever year on Labor Day, never knew that

I'm babbling away, but all told we did approx 950 miles, snapped approx 200 photos,
used 11 tanks of gas, 1/2 can of SeaFoam,
3 Quarts of OIL, and no I didn't mix it in the gas, and no the oil isn't leaking, I DO have oil leaks but none are that bad.....gotta be burning it