[franksc]

i have a 2004 sportster 1200 custom i recently put drag pipes no baffles on it when i let off fuel i get a lot of backfiring how can i fix this?

[Red Rider]

Ya gotta tune your carb, as you already know. You'll need to pass along what carb and jetting you have and then you'll get all the advice you need. Your primary altitude will be a factor, especially if you don't have a stock CV carb - but I'd guess you do. Decel backfiring is from running too fuel rich - if I remember right. Someone else will correct me if I'm wrong, of that I am certain!

[ringo912]

Also...when you run a drag pipe without baffles you lose performance, ie: horsepower and torque. It is also a lttle difficult to tune a carb running striaght drag pipes. You need some kind of baffle to stop reversion of the sonic pulse on the exhaust stroke. Drag pipes are really designed for drag bikes that have built motors with a lot of horse power. They may sound good, but they reduce the overall performace of a street bike

[scottf]

If you are looking for performance, drag pipes are the worst pipes you can have. They have no baffel, and you need back pressure for your engine to perform. The backfiring is caused by a to lean condition. You need to re-jet your carb to bigger jets. Any time you change either the air filter or the pipes, you'll need to re-jet.

[chucktx]

you will never be able to tune your bike for the street with drag pipes. about the only tuning you can do with open drags is wide open throttle. you can install a washer in the pipe and get some pretty good tuning results. as the others have stated....very llimited to tuning with drags.....hence the name!!