Backfiring Letting Off The Throttle

[Y2K81]

Well normally I'd take the carbs apart and soak things in seafoam but considering this is fuel injection I'm asking around.

Stock 00 motor
Yamashiki exhaust

Looking for ways to stop the backfiring when. I let off the throttle at high rpm.

 

[sixpack577]

New problem, out of the blue?
Have you changed anything?

 

[Mike Chambers]

Well normally I'd take the carbs apart and soak things in seafoam but considering this is fuel injection I'm asking around.

Stock 00 motor
Yamashiki exhaust

Looking for ways to stop the backfiring when. I let off the throttle at high rpm.

I run 2 brothers, and when I throttle off it back fires as it's sucks air back into the system, I find running an injector cleaner every so often will reduce,your yoshis may be doin same

 

[sixpack577]

Have both of you removed the P.A.I.R valve?
Blocked it off (marble mod), or installed block off plates on the reed valves in the valve cover?
If not, that's the problem.

 

[Mike Chambers]

Have both of you removed the P.A.I.R valve?
Blocked it off (marble mod), or installed block off plates on the reed valves in the valve cover?
If not, that's the problem.

When I spoke to Ray Clee (nz top mechanc,as mine is minor it's caused by air being sucked back up cans , normal but not a concern

 

[David Offor]

I've never heard that one before, I'm running a pair of open renegade cans on mine and I'm not getting any backfiring on the overrun, I was however, getting back firing, before changing my faulty ckps/stator assembly.
I think the mechanic is talking about backpressure but most bikers are running non legal exhausts and I can't believe they are suffering from backfiring on overrun.
Can you try putting the stock cans back on and see if that clears it up, it helped mine before I found my fault, if it doesn't sort out your backfiring, then I'd say you have a sensor fault.

 

[jermzfree]

The marble mod will probably fix your backfiring problem. Could have a faulty pair valve diaphragm allowing air into the exhaust during deceleration. Find a kid in your neighborhood, give him a quarter for a small sized marble, then stick it in the clean air return hose located on the right side of the air box.