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100 oct unleaded to 110 oct leaded

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I have a 07' YZ250 running on 100 octane unleaded mixed 32:1, and its perfect! If I was to switch to 110 leaded fuel, would I need to go up or down on jet size, or will it probably be ballpark the way it is? Thanks

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The octane rating of gasoline defines the gasolines anti knock index, the ability of the gasoline to stand up to detonation. This in turn, has nothing directly to do with jetting.

You will not see any increase in performance, what-so-ever.

You will see more money coming out of your wallet.

The octane rating for your bike as defined in the manual is 95 RON, which is not 95 AKI which is the standard that we use here in north america. Even if you live overseas, 100 octane is plenty in terms of what the engine requires in order to prevent detonation using the stock jetting, and the stock compression ratio.

Whenever you increase the compression ratio in your bike you need to increase the octane rating that it was designed for, this is the only time you'll need higher octane rated gas.

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My head is milled, and can't run less then 100 oct. Thought maybe the lead would affect the jetting some.

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Not a motorcycle, but still 2 stroke motors.......

Not exactly the answer to your question either as both are leaded.

In my outboard hydroplanes I've been able to switch between VP C12 and 100LL AV gas without making any changes at all in timing or jetting. No difference in performance either....

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