Popping through the exhaust on decel

[ricoman]

Had the same problem on my 05 RKC together with surging between 1800 and 2400 rpm. The surging was about to make me crazy. Installed a TFI from Dobeck and adjusted it a couple times. No more decel popping and no more surge. I went with the TFI as I don't plan any more engine mods other than the V&H true duals, SE slip-ons, stage1, and air cleaner already on the scoot. If I do any more I will go to a sert install. I do not think a properly tuned sert should result in any decel popping. There have been so many posts on ths (and similar topics) and most agree the sert install should leave no popping or surging.

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[tsprinkle]

I have an 06 Ultra Classic. I put up with the popping and backfiring for almost a year. At my 10,000 mile service I was complaining about it and the service manager came out. He looked at my VIN number and told me there was a service bulletin requiring a differant set of fuel injectors. They relplaced the injectors and the bike has never run better. I also found out that unless there is a mandatory recall, you may never hear about a service bulletin on your bike unless you complain about something it covers.
I think I was just lucky that the service manager heard my complaint and knew of the service bulletin.

[beemer737]

2000 88 EFI stage 1 with S/E slip ons, it popped for 6 years, recently added PCIII, S&S 510g cam, I can't get it to pop, same mpg.

[Taterdog]

If you get a PCIII and load the correct map for your config, just bump the 0's in the 0% throttle position up to 15's or 20's. That should take care of your popping.

I'd look into the V&H Fuelpak also -- getting very good reviews. Don't know much more about them thanthat. I've got a PCIII (my second as my first failed), but bike runs great with it.

Good luck, CB.

[BGHV65]

Hell, my '03 Ultra pops and burbbles on decel and has since putting on the V&H Pro Pipe. I also have the PCIII and a K&N, had it dynoed, etc. But you know what? I like to hear it, sounds cool to me. It was running way rich before the dyno and hasn't changed as far as the popping/burbbling. I may tinker with adding fuel in the low cells at some point but like several on here said, I don't worry about it...I just want to ride. Now if it ever backfires and blows the muff off, I'll probably look into what happened and fix it........right after I change shorts.......

[gunmetal]

2003, twin cam 88, EFI, vance hines, a simple way to stop the popping on deceleration is to simply add a tiny bit of throttle.

[2000FiveOh]

Originally Posted by Anthony8858

I have an 05 RK with SE pipes(recently changed to V&H mufflers), Air filter, download. I too had popping on decel......But NO MORE!!!


Here's what to do:

First off I have to correct a few responses. The condition is caused by a lean condition, not a rich one. When you let off throttle, the bike needs a little more fuel in the 0% throttle position. The ONLY way to fix your problem is with a fuel manangement system. I recommend a power commander III. This will allow you to connect your bike to your PC and simply raise the fuel value on decel (0%), and eliminate your problem.

You won't get a decel pop unless there's unburned fuel in the exhaust. Unburned fuel equals rich, not lean. If the combustion process completely burned all the fuel there'd be none left to ignite. But, we all know these engines are not that efficient. Most decel pops are a result of an exhaust leak, which creates a leaner condition. A leaner condition, not necessarily too lean.

The bottom line is these engines will pop and fart through carb or the EFI. On stockers, the mufflers hide most of the pops. On free flowing systems the sound is heard more, obviously. There's no way to totally eliminate the popping.

[2000FiveOh]

Originally Posted by Taterdog

If you get a PCIII and load the correct map for your config, just bump the 0's in the 0% throttle position up to 15's or 20's. That should take care of your popping.

I'd look into the V&H Fuelpak also -- getting very good reviews. Don't know much more about them thanthat. I've got a PCIII (my second as my first failed), but bike runs great with it.

Good luck, CB.

15 or 20 is way too much. Each bike will respond different. The best way to do this start at 5, that should quench the popping. If it doesn't, bump it to 7, then 9, etc, until the popping is gone.

I wouldn't increase anything in the 1000 rpm box. Try 1250 - 2000 and see what that does. If that doesn't work, bump it to 2500, etc.

+3 in the 0 column, from 1250 to 2500 eliminates any audible popping in my bike. Like I said, each bike and tune is different, so it's just a matter of experimenting, without tossing unnecessary fuel at the problem.

[Anthony8858]

Here's how I got rid of mine:

I hooked up my bike to a laptop computer, with the PCIII software running.
If you rev the bike a bit, you'll notice what RPM's the bike decel pops. It's at THOSE RPM's, that you gradually increase the fuel in the first column (0%) until the popping is gone.
Typically, most bike seem to respond by gradually adding fuel in the 1250-4000 RPM range in the 0% column. In some cases, I've had to add some fuel in the 5% column around 2000 RPM's

[goodbirds]

I've noticed on my 07 Ultra that the popping or grumbling occurs below 2000 rpm. Above 2000 rpm, and five seconds after closing the throttle, the engine sounds like a engine brake has engaged. Is it a fuel shutoff situation then?

I really don't mind the soft grumbling sound on decel. Sounds like a motorcycle.