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Octane boost

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Old Dec 2, 2008 | 07:54 PM
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Question Octane boost

Where I live, the best octane you can get is 91. When I shift fast and hard I hear that clatter you get with cheaper gas. Is there a booster that works especially for the V twin, or is the normal gas treatments available just as good? Any recommendations welcomed.
 
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Old Dec 2, 2008 | 07:57 PM
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tune it to run on 91 ? cost alot but its A ONE TIME DEAL.
 
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Old Dec 2, 2008 | 08:18 PM
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During the gas shortage back in Oct. all I could get for a couple of weeks was 87 octane , I just put in about a 1/2 bottle of the STP boost at each fill up with no problems.
 
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Old Dec 2, 2008 | 08:33 PM
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H.D. part #99893-91A works well.
 
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Old Dec 2, 2008 | 08:37 PM
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Been running 91 octane for years in a mid bulid TC 88 and never had a problem. Not sure gas is the problem but your bike, your call.

Just my 2 bits,

Krusr
 
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Old Dec 2, 2008 | 08:45 PM
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stock 07 and 08 are prone to octane knock there is a free download from harley. but why not dyno it and know that its tuned for the type of riding u do
 
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