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Discussion Starter #1
I posted this deep in a BS thread and would like it to get more light that it did. For those of you that have access to this stuff give it a shot! Ethanol burns cooler which is great and all, but when you toss some more timing to the mixture it becomes great!!

Hell at the least it is a cheap race gas (locally about 2.50). I would run up to a 13.5 compression piston with out any problems. I had my predator with 12.5 compression piston tuned for it (yes you HAVE to tune for it) and it ran amazing!!! The exhaust smelled pretty cool. Kinda like vodka. I talked to my dyno guy and he said that you can have two maps made for your bike. One for gas, and the other for E-85 and switch maps on the PC3 on a handlebar mounted switch. If you ever have to run other fuels this would be great.


E85 is 105 Octane, and requires you to much much richer than gasoline.

Theres a few differences you'll have to note:

E85 has a lower energy content that gasoline. This means less power per gallon. 1 gallon of gasoline contains 114,132 BTU. 1 gallon on ethanol contains 76,000 BTU. 1 gallon of E85 has roughly 83,263 BTU. MOST E85 isn't a straight mix of ethanol/gasoline. Its 85% denatured alcohol (~95% ethanol, ~5% gasoline). Thats 27% less energy.

Another thing is the A/F ratios for E85. The Stoichiometric ratio of Gasoline is 14.7:1, while it makes max power around 12.5:1. E85 has a stoichiometric ratio of between 9.73:1 and 9.8:1 (based on pureness), while max power is made as rich as 7:1, although recommended around 8:1.

So, less power, and richer A/F mixtures? Not exactly. Consider the BTU/gallon vs. the A/F ratio required to run E85.

Compare the stiochiometric ratios of the two. Gasoline is 14.7:1, while E85 is 9.8:1. I think my math is a little off on this but thats 50% more fuel. 1.5 (150%) x 76,000 = 124,000 BTU. Thats slightly higher than the power produced by a gallon of gasoline. Now take the max power rich A/F ratio of gasoline and E85. Gasoline is 12.5:1, while E85 is about 7:1. Thats about 78.5% more fuel than gasoline. 1.785 (178.5%) x 76,000 ~ 148,000 BTU. Thats roughly 29% more power than gasoline!
What else does this mean? Just by switching from gasoline to E85 and adjusting it to the max power rich A/F ratio in your turbocharged engine, you could pick up roughly 15% power. Another thing to consider it the octane of E85. Its 105. Think about running 105 octane gasoline in your car with a 7:1 A/F ratio. Detonation? Probably none. This means you can severly raise boost or advance your spark for higher power and not have to worry about detonation.

Another thing to consider. E85 is about as cheap as 89 octane gasoline, which is even cheaper than the 93 most SRT guys run. The only downside is that you'll probably see roughly a 25% decrease in MPG if you adjust the A/F ratios to run at the stoichiometric ratio of the E85 (you still won't have to worry about detonation at this ratio). With the increasing gas prices and the ever decreasing ethanol prices (it IS a renewable resource), in the years to come it may become cheaper to run on E85 than gasoline.
 

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Is there any kind of corrosion problem with it? If I remember E85 is quite a bit more corrosive then gas because it burns so clean so if you ride it and put it away for a week, could there be a problem?
 

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Discussion Starter #3
Is there any kind of corrosion problem with it? If I remember E85 is quite a bit more corrosive then gas because it burns so clean so if you ride it and put it away for a week, could there be a problem?

People tell you this, but they have no experience with ethanol. Maybe with alcohol but that stuff is quite different.

I left it in my predator for weeks at a time with no ill effect. I even took apart my carb and looked for signs of deterating (SP?) of the fuel system, and nothing!!!
 

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People tell you this, but they have no experience with ethanol. Maybe with alcohol but that stuff is quite different.

I left it in my predator for weeks at a time with no ill effect. I even took apart my carb and looked for signs of deterating (SP?) of the fuel system, and nothing!!!
Cool thanks. :thumb:
 

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would a stock injector work or do you need to go up to a 650 injector and would you not burn twice the amount of fuel there for your costs goes back up if you run E-85
 

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Discussion Starter #7
Jdog, I have never played with the injectors on the rappys so I dont know the what the stocker can handle. I would immagine that with you big build you are aready pushing the stock injector past 70% duty cycle, So i would not push it.


E-85 works on about anything, including 660!
 

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if i would run alcohol i would go for methanol but i would not be opposed to running E-85 in my wifes bike also were do you get E-85 i have not seen it in AZ.
justin
 

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Westren States Petroleum in Phoenix has it. TOM
 
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