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yz 250f gas

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Your bike will make more power with a good 93 pump than with 110 octane fuel. Octane is way to high for even mod 250F's and fuel burns to slow.

Shouldn't ever need more than 100 octane. Try VP MS98L it is 96 Octane. If you really want the fuel to make a difference you need oxygenated fuel like MR9, MRXO1 or U4.

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Your bike will make more power with a good 93 pump than with 110 octane fuel.

this statement is true provided all things are equal. Hot Rod mag proved this last year in a dyno test (using a v8 car motor).

Octane is way to high for even mod 250F's and fuel burns to slow.

however, this statement is entirely false. octane has ZERO, NADA, NOTHING to do with fuel burn rate. that is handled by the chemistry of the fuel, not octane.

for the bazillionth time, octane is the value associated with the resistance of a fuel to ignition. that is all!!! octane is not horsepower, it is not a fuel accelerant, it is not magic. what it does do is prevent the fuel from going boom to early (ie pre-ignition or detonation) and that is it.

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We use Monster 110 leaded race fuel. I use it for a number of reasons; jetting is so much easier to dial in, the fuel is always the same everytime I buy it, the lead helps cushion the valve seats, and it smells good. Plus with the high compression piston, its peace of mind knowing that it won't ping when its hot, muddy, and boiling over on the single track. :applause:

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I've tried several different types of race gas. My bike only like about 1 gallon of race fuel/5 gal of pump. Anything more than that and it starts to run poorly.

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Too much octane and your bike will run poorly. U4 is 92 octane but is oxygenated and will give you a boost that you can notice........1.5 hp is my guess.

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Too much octane and your bike will run poorly. U4 is 92 octane but is oxygenated and will give you a boost that you can notice........1.5 hp is my guess.

And insn't is $8 a gallon?

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So this discussion brings up a good point...

Here in California we have oxygenated gas during the winter as required by law. So the 91 Octane gas (they round down now instead of up, it used to be 92 octone using them R+M/2 method) has 5.7% Ethanol used as an oxygenate. Does it matter what is used as an oxygenate to produce that extra power? I'd be interested to see if changing what is used to oxygenate would produce different power. You could use MTBE, Ethanol, Methanol and other things to oxygenate gas, so I'm wondering which produces the best results.

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And insn't is $8 a gallon?

No way! Whoever told you that is feeding you a bunch of BS. We only paid $60 for a 5 gallon pail. :applause: Thats only $12 a gallon......but it smells so good!

Its not for playing......we were testing how it works in a race bike and will use it for racing. Its worth a try if you get a chance to use a gallon. Just use in straight no mix and store in the metal can indoors.

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Does it matter what is used as an oxygenate to produce that extra power?

maybe in ways you didn't even consider.

for instance, ethanol is gonna attract water. big time.

so storage is a big concern.

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:applause: man i know im lucky...:lol:

my local gas station(which happens to be right across from my local bike shop, no crap) carrys sunoco 112 octane leaded race gas!

all the local race car teams use it along with all the local racers :applause:

only 5.99$ a gallon...twice the cost of 93 around here but the performance is worth it to me!

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SUNRUH you are absolutly wrong when you say VP 110 is NOT to high an octane fuel for even mod 250F's and that VP 110 does NOT burn to slow for a 250F.

We have tested lots of VP fuels in my son's 250F's and even the best mods with the highest compression have never needed more than 100 octane to prevent detonation. Usually 96 is plenty. Running VP 110 straight in a 4 stroke motocross bike is a waste of money and will result in less power than 93 pump fuel.

In our experience, VP 110 just like VP C12 burns way to slow for 4stroke motocross bikes. The only time we have had any luck with fuels like VP 110 or C12 is when they are mixed with pump fuel and used in a mod bike for practice or to run through the bikes after draining oxygenated fuels.

Ranting about something for the "bazillionth time" that has nothing to do with my statement means nothing. Anyway, we all know the only person that has ever even counted to a bazillion would be Chuck Norris when he counted to infinity those 2 times.

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