Race Fuel Question

We have a yz112 supermini and it has 14.5:1 compression. What type of gas do you guys recommend using. On our previous bikes we have mixed C12 with 94 pump gas 50/50. That worked well and the price was fair to do so. But will a 14.5:1 compression ratio be too high for straight C12? on VP's website it says C12 is designed for motors 15:1 and under. A close by store sells C14 but they want $130 for 5g. That is insane!

Anybody found a cheaper way than running the real expensive stuff? Like running C12 with octane boost etc.?

Also has anybody tried AV gas? I heard it burns great and is very cheap compared to race gas. But you have to run your jetting extremely lean?

Any info is appreciated. We spent a lot on this motor and don't want to blow it up... but don't want to pay $26 a gallon if at all possible! Thanks

FWIW ive always heard not to run AV gas. Many articles on this and other forums explain why. It is tempting i know, and a lot cheaper than VP's or Sunoco's fuels. Have you tried talking to VP? Maybe a person to person chat with their tech line would help. Also, have you looked at the race gas chart on their website? i believe it suggests one or several fuels for class/type, including AMA rule restrictions. FYI i get MS109 its reasonably priced, im not sure if it will work for your application.


Edited by meinmoto

Straight C12 will work perfect for your bike, 100 LL isn't made for the revs or throttle response you're looking for

av gas is a great fuel. for modified 2 strokes.

but for your application, straight c12 should do the job perfectly. God i love that smell.

Edited by adam8781

So if I had a 105 cr85 that runs on race gas, I'v herd that if I put a lower octane gas in it, it wouldn't last very long. So basically if I were to start putting lower octane gas in it, what would I need to do?

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