Replace air cut valve ass. or reed valve.?

[Mobile]

RE: the excessive backfiring can it be caused by a bad "Air cut valve"

or a bad "Reed valve" and has anyone had to replace them? and if so are there any after market ones available, and if so where from?

and could this be the reason for my excessive backfiring when down shifting, as my carbs are synced properly. I shall look for your response.

Thanking You..Mobile

[BuddyRich]

I'm pretty sure Reed valves are only used on 2-stroke engines.

[1BigDog]

Try plugging your AIS system. That usually does the trick. Im sure you can find info on it with a search. I took mine off completely but its a PIA.

[V7Goose]

RE: the excessive backfiring can it be caused by a bad "Air cut valve"

or a bad "Reed valve" and has anyone had to replace them? and if so are there any after market ones available, and if so where from?

and could this be the reason for my excessive backfiring when down shifting, as my carbs are synced properly. I shall look for your response.

Thanking You..Mobile

It is possible for the AIS valves to be bad, thus causing your problem, but I think that is highly unlikely. They would be easy to test with a vacuum pump (or even just sucking on the vacuum hose).

 

Your original post referenced plugs in "egr" hoses - I have no idea to what you were referring, since this bike does not have exhaust gas recirculation, and there should not be any "plugs" in anything, so that suggests something has already been modified.

 

I suggest you make sure you do not have any vacuum leaks in the caps or vacuum lines on the intake nipples. In addition, new plugs may help, since the popping is caused by too much unburned fuel getting blown into the pipes. Finally, if your AIS system has been modified at all, I can't help you much, since I know how the bike is SUPPOSED to work when set up properly. Changing that just introduces too many variables to attempt blind troubleshooting from a computer.

 

Here is another thread with a lot of discussion about this problem, including information about why you do NOT need to disable the AIS to solve it. In fact, disabling the AIS will simply make it harder to actually find and fix the real problem.

http://www.venturerider.org/forum/showthread.php?t=22961&highlight=afterfire

Goose