I took the seat off my bike and found a RevTech DFO........ i had to do a search for this product as i've never heard of it before

 

[sm=massbounce.gif]Humor … Here is my two cents on the backfiring … First improper tuning is the likely culprit … Second, there maybe a leak somewhere in the intake … Third, the left muffler on stock bikes with the3 pipe-stock exhaust system has a smaller exhaust exit in the (left muffler). (To keep it from sucking of air)
The stock rear pipe splits off, one right one left. The rear right ties back into the front pipe. The left pipe is sort of a dummy, feeding the restricted left muffler. When your engine decelerates the headers turn into an aspirator, sucking spent gasses from the head pipes. Thus sometimes sucking cold air up from the left muffler and sometimes causing a backfire. Aftermarket mufflers have large baffles that may let more cold air into the exhaust system, making it pop more .. Now this may be all BS but that is my initials, so I am sticking by this story.

 

running a little lean fuel pak V&h