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rejetting carb after installing aftermarket pipes?

3693 Views 4 Replies 5 Participants Last post by  AzFAL
installed samson rolled thunder slip-ons on 2002 flht and changed slow jet to 48. still pops once in a while but getting alot of backfire on deceleration. from what i read, bike still too lean but looking at pipes, somewhat black instead of brown. should i adjust idle screw out to 2 1/2 turns, believe stock is 2 turns or should i change main jet? any info would be appreciated. by the way the pipes sound excelllent.
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The beauty of jets is you can change them. The sure fire way is to dyno the bike. Next bet is to read a set of new plugs. Performance pipes will give you poping on deacel- from a high rpm, what alot of riders do is try to have the jetting close enought to minize the pop pop pop. Bottom line is if the jetting is right on you still could have the pop.
A suggestion before you start re-jetting. Your new pipes do not provide the back-pressure of your stock pipes. I would suggest trying a set of power cones as a first step. They go in the top of the pipe by the heads. Then put in some new plugs and read them to see if you need to go richer or leaner.
Make sure you use some Permatex High Heat copper silicone on the slip-on joints. If they are sucking any air in on decel they will pop. Have had this happen a couple of times and when sealed properly they quit popping. ;)
Did you guys notice the date of the OP. I bet he's got it fixed by now, I hope. :)
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