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backfiring...
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Tiny Pimpled Genitalia
 
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backfiring... - April 5, 2011, 11:18 AM

so i'm a little late with my 12,000 mi valve check / adjust. was planning on doing it over the winter buuuuut it hasnt happened yet.

so i get the bike out last week to tool around, and after it warms up i realize i get the occasional backfire on decel (chopped throttle); not the usual little pops and burbles that i'm used to, but more of a "whumpf" than a "bang". could be gas related i guess, it has a small amount of stabil and seafoam in the tank from winter...

header has never been off, so i'm thinking exhaust gasket is an unlikely culprit.

exhaust valve lift out of spec?

thoughts?

ps. this is a bucket/shim setup


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whoa preppy......
 
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April 5, 2011, 11:24 AM

have you done anything to the bike over the winter? Maybe check the air filter? Backfires and pops on decel is usually due to a lean condition. If you don't get the air box cover on tight or if you installed a K&N filter you'll see that happen.


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April 5, 2011, 03:10 PM

does have a k+n... installed a couple years ago. havent opened the airbox for awhile.


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April 5, 2011, 03:58 PM

Depends on the bike...you dont let us know what it is...depends on carbs vs Fi...
Can be (most likely) just old gas...even with Stabil, they don like old gas...flush and refill...

Might be plugged air bleeds on carbs.....
Paar Valve, TPS or exhaust mid-valve ........


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April 5, 2011, 04:04 PM

fuel injected, 2002 daytona 955. no exhaust valves / butterflies


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