fatboy poping

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Apr 27, 2009 | 08:46 PM

64 stroker

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5th Gear

Joined: Feb 2009

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fatboy poping

I have an 04 fatboy which is making a poping sound or backfire when letting off the thoutle when im at a higher rpm an sometimes it seems like it stumbles when giving it the gas ive changed the exhaust gaskets an even changed the pipes was wondering if i might have to rejet it any help would be welcome

Apr 27, 2009 | 09:03 PM

DaddyKnuck

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Joined: Aug 2007

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From: Blairsville GA

Quote:

Originally Posted by 64 stroker

If you're running a non-stock air filter and pipes and haven't rejetted it's probably lean as a snake. You might try a couple of cheap tricks before spending the money on a jet kit. Drill out the aluminum plug covering the idle mixture screw. Use a small bit and drill cafefully the cover is only a few MM thick. Once you pry the cover out, turn the jet clockwise in until it lightly seats. Pay attention to how many turns in. It iwll probably be about 1 turn, maybe less. Open it back up (counterclockwise) as many turns as you tightened it, plus 1/2 more turns. This is a good starting point.

Buy a few 3 MM flat washers. Pull the top of the carb and carefully remove the diaphram carefully and remove the slide. Pull the needle and space it up with one of the 3MM washers. Put it all back together and warm the engine up. Adjust idle so the bike runs smooth. Turn the idle mixture screw slowly in and then out 1/2 turn. At the point that the engine runs best (idle increases) you are good. If you still have a lean pop, you can add another washer for a little more middle.
Good luck.