deceleration back fire [Archive] - Kawasaki Motorcycle Forums

deceleration back fire

07-30-2012, 05:06 PM
Hello Gentlemen,
I was wondering if anyone has made a blocking plate for the reed valves on the 1700 engine. I have installed the blocking plates on my Honda 1800 vtx F model. When I blocked of the deceleration popping stopped and the engine seem to run alot better as far as performance.
I am considering using rubber caps to block off the reed valves to stop the air injection to the exhaust.


uechi kid
08-03-2012, 02:38 PM
I can't seem to find any block off plate. In the mean time you might consider marbling the air hoses.

Vaq Now
03-02-2013, 12:50 PM
Depends on what year bike he has my 2011 vaquero air hose is under the head covers the only way to get to it . They do make covers for the 1500/1600 nomad. just what i'v read on other forums.

09-15-2013, 02:21 PM
I have 2012 voyager an changed exhaust to [email protected] slash cuts an a cobra fl2000 fuel processor. It popped bad. Talked to the local dealer ship an plugged air hose going to reed valves. remove right air cleaner cover an plate on throttle body.Plugged air hose at about 10 oclock with just a marble.It took out about 90 percent of popping an fuel miliage went way up.

10-03-2013, 12:15 AM
Have a 2011 Voyager with V&H slash cuts and have two friends with Vaqueros same mufflers all are plugged (helped some) all still pop. The V&H's did help with some of the heat problem and increased the performance alot, didn't realize how much until in put the stock mufflers back on for a week, back with the V&H's and the popping! Let me know if you find a cure...PLEASE!

10-04-2013, 12:31 PM
popping on deceleration is a sign of running lean. There are two possible causes:

1) If you have reburn emissions controls, when you decelerate, air gets pulled into the exhaust and allows the unburned fuel (however little) to reignite. Can also happen with exhaust leaks, but that's less common.

2) The more common cause is that reducing the backpressure has changed the intake draw in your carb and you are running lean because of it. If you can, try applying "a little" choke and decelerate. If the popping goes away, it's time to rejet. The fact that the factory pipes to NOT pop is a good clue that this is the problem.

Since you have a more recent bike (my experience is from OLD bikes), you might also be able to adjust the electronic ignition using "Power Commander" (IIRC) to adjust the performance parameters.

Regardless, you are probably experiencing an slightly over-lean condition. Getting more gas into the fuel-air mixture is the most likely solution.

10-12-2013, 11:06 PM
My buddy has a fuel pack of some kind that is supposed to adjust multiple times a second/minute think its a Cobra brand and he has the same popping as I do. I think our problem is #1, sucking cool air back into the pipes. Have been going to try to make a screen baffle and see if it would warm the air and stop the popping.?

11-14-2013, 09:22 PM
Can also be by a exhaust leak, check your bolts at the head had some guy's say theirs have come loose and also where the mufflers slip in, make sure it's tight. When I changed my exhaust the decel popping was more noticeable. Plugged the hose when I changed my intake out and adjusted my fuel processor and 98 percent of it is gone. I would check for leaks and if not that look into a fuel processor. I would stay away from the Cobra, haven't read to many people with good results, just my opinion.