Rolltide Posted May 25, 2014 #1 Posted May 25, 2014 Engine will backfire on deceleration sometimes. Dealer synchronized carbs and will still do it. Read about an AIS system and a post on how to fully plug. Can't seem to find can anyone help?
MikeWa Posted May 26, 2014 #2 Posted May 26, 2014 Page 6-16 in the Yamaha service manual. It is the job of the two air cut-off valves to shut off air flow in the ais system during deceleration. This is to prevent popping in the exhaust. They are controlled by two vacuum hoses. One at the base of a left and one at the base of a right carburetor. Make sure those vacuum hoses are good. If you are getting popping either one of the cut-off valves is not working properly or air is coming in somewhere else. If the engine is stock this sounds like a warranty issue to me. If the exhaust has been modified start checking there. Mike
Freebird Posted May 26, 2014 #3 Posted May 26, 2014 Here is a thread and some pictures. http://www.venturerider.org/forum/showthread.php?t=485
Rolltide Posted May 26, 2014 Author #4 Posted May 26, 2014 Thanks for the advice and link. This system reminds me of the air systems that GM put on cars in the eighties.
RSTDdog Posted June 1, 2014 #5 Posted June 1, 2014 My AIS is intact and the exhaust does not pop. When I did have exhaust pop on decel I found it was related to the carbs. I removed carbs, disassembled, cleaned, set the float levels and replaced the o-rings on the needle valves, re-install, carb sync, popping went away. Unless you bought your 09 before today in 2009, it is still under the 5 year warranty. Dealer should fix the popping issue, likely carburetor related.
vzuden Posted June 2, 2014 #6 Posted June 2, 2014 I had some popping once and a carb sync and a shot of Sea Foam took care of it. AIS has not been touched and I've got 30,000 miles on it.
kevin-vic-b.c. Posted June 2, 2014 #7 Posted June 2, 2014 The thread by Freebird is very good and very easy to follow. That being said... do not expect backfire to go away if it is carb or plug related. The AIS will or may make the issue worse but it is unlikely to fix the issue. Just my opinion after being there and chasing that. I am Canadian so cannot say it is my worth because we don't have pennies anymore so with inflation it has to be my nickels worth. Just saying
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now