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Old 05-07-2013, 05:32 PM
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LR Jerry LR Jerry is offline
Motorized Bicycle Elite Member
Join Date: Dec 2011
Location: Oak Ridge, TN
Posts: 1,019
Default Re: Brand new to gas bikes.

Most of these two stroke engines are low compression so that they're easy to crank. So unless you've up the compression to around 15:1 don't run premium. 87 is best for anything 9.1:1 or less. It has to do with a process called detonation . This is the point of combustion due to compression. The objective is to have the detonation and the spark at the same time so you get maximum burn. Running premium in a low compression it will spark before the detonation point. This results in power loss and residue being left in the cylinder. If you run 87 in a high compression the detonation point occurs before the spark resulting in knocking and the engine still trying to run after its cut off. If you up the compression it will give you more power but also will be harder to crank.

I use to be making the same mistake about premium gas. Like most people I thought higher price and octane more power. This forum taught me better. To conclude unless you've up the compression considerably use 87.
Land Rider Jerry

Last edited by LR Jerry; 05-07-2013 at 06:13 PM.
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