Exhaust Backfire
Thread Starter
|
Road Warrior
Joined: May 2007
Posts: 1,586
Likes: 1
From: Clinton, Ohio
RE: Exhaust Backfire
I have a feeling the previous owner just put the pipes on it, and nothing else. I haven't been able to check the A/C since I don't have an allen wrench big enough to get the cover off yet.
Ultimate HDF Member
Joined: Feb 2007
Posts: 7,663
Likes: 7
From: Northeast Ohio
RE: Exhaust Backfire
Number one issue to look for when popping on decel is an exhaust leak. It sucks in addtional air into the exhaust to get the A/F mixture right to where it actually ignites (pops) in the exhaust. Think of your propane grill, it wont light if you have turned it on and have not lighted it right away. It needs more air to ignite and that is why you eventually get the "whoosh" when it lights.
Those of you richening it up at idle to eliminate popping are getting the mix of fuel going into the pipe with air to the point where it won't ignite- it is out of the flammability range. This is a fix for carburated bikes.
Fuel injected bikes actually lean out the air fuel on closed throttle deceleration, not allowing enough unburned fuel into the exhaust to ignite. I run a DTT and the A/F ratio on a closed throttle decel actually goes up to about 18:1 or better. This is not allowing any fuel into the cylinders and ultimately being pumped out into the exhaust. How do I know the A/F on decel, I can download the last 2 hours history of what the A/F and timing is based on throtle position. Big advantage of running the DTT TCFI IID.
Those of you richening it up at idle to eliminate popping are getting the mix of fuel going into the pipe with air to the point where it won't ignite- it is out of the flammability range. This is a fix for carburated bikes.
Fuel injected bikes actually lean out the air fuel on closed throttle deceleration, not allowing enough unburned fuel into the exhaust to ignite. I run a DTT and the A/F ratio on a closed throttle decel actually goes up to about 18:1 or better. This is not allowing any fuel into the cylinders and ultimately being pumped out into the exhaust. How do I know the A/F on decel, I can download the last 2 hours history of what the A/F and timing is based on throtle position. Big advantage of running the DTT TCFI IID.
Road Captain
Joined: May 2007
Posts: 596
Likes: 7
From: Illinois
RE: Exhaust Backfire
Mine pops like crazy, too. Mostly on decel, but sometimes if I'm in 1st or 2nd gear,off idle, but not revving, I hear the "pop......pop..pop.pop......pop .I told the dealer about it, which ageed it is lean, but said there's nothing they can do, until I do a stage 1. They said it's $150 not including dyno runs, and I have to have them install the parts, to keep the warrantee. WTF, I can't afford the parts, let alone what they charge for labor and tuning. Imiss my carbs...
Intermediate
Joined: Jun 2007
Posts: 40
Likes: 0
From:
RE: Exhaust Backfire
I had to wait five months before V&H came out with pipes for my '06.
(I refused to put slip ons..on)
Instead, I cut the stock mufflers right past the weld and blew out the stock baffles and wadding. The bike ran fine. After I installed the V&H's, I remapped at the dealer along with the HD hi flo air filter.Then I started to get popping upon decellerating.
I heard of two fixes to the problem.The PCIII should do the trick if done properly.
I also was told that removing the cross overs and welding the holes may solve the backfire. I haven't done either....yet.
(I refused to put slip ons..on)
Instead, I cut the stock mufflers right past the weld and blew out the stock baffles and wadding. The bike ran fine. After I installed the V&H's, I remapped at the dealer along with the HD hi flo air filter.Then I started to get popping upon decellerating.
I heard of two fixes to the problem.The PCIII should do the trick if done properly.
I also was told that removing the cross overs and welding the holes may solve the backfire. I haven't done either....yet.
Thread
Thread Starter
Forum
Replies
Last Post
irlm1
Ignition/Tuner/ECM/Fuel Injection
30
Apr 22, 2023 06:52 PM
