New to FZ - Backfire on decel....

[Rage01]

I just purchased a low mileage (about 1300) 2009 FZ1. The previous owner put a Yoshimura Exhaust and the bike is backfiring a bit during deceleration. No changes have been made to the airbox or anything else. I think I may need a Power Commander...any other ideas?

 

[Oldschool]

I just purchased a low mileage (about 1300) 2009 FZ1. The previous owner put a Yoshimura Exhaust and the bike is backfiring a bit during deceleration. No changes have been made to the airbox or anything else. I think I may need a Power Commander...any other ideas?

This is totally normal and is caused by the AIS system. A.I.S. is the air injection system which injects fresh air into the head on the exhaust side to ignite any unburnt fuel to help keep emmisions down. With an aftermarket pipe you hear this much more than with the stock muffler. This is because the valve in the stock muffler (just behind the mid pipe) closes upon deceleration (on the Gen IIs) to quiet this noise. If it really gets on your nerves you can remove the A.I.S. system or just block the intake hose from the airbox (where it draws it's air).

Check out this thread: http://www.998cc.org/forum/gen-ii-how/7810-how-roth-ais-block-off-plates-installation.html#post33310

 

[whittlebeast]

What Oldschool said.

Beast

 

[viking1]

AIS block off + 1. It worked for me.

 

[Rage01]

This is totally normal and is caused by the AIS system. A.I.S. is the air injection system which injects fresh air into the head on the exhaust side to ignite any unburnt fuel to help keep emmisions down. With an aftermarket pipe you hear this much more than with the stock muffler. This is because the valve in the stock muffler (just behind the mid pipe) closes upon deceleration (on the Gen IIs) to quiet this noise. If it really gets on your nerves you can remove the A.I.S. system or just block the intake hose from the airbox (where it draws it's air).

Check out this thread: http://www.998cc.org/forum/gen-ii-how/7810-how-roth-ais-block-off-plates-installation.html#post33310

I understand. I had to do the exact same thing with my Yamaha Road Star. Well, thanks for saving me $350!!

 

[johnnyontherocks]

I wold also disonnect the plug that goes to the AIS pump motor while you have the tank up.

 

[Missyl1713]

If you don't have emissions tests in your area I'd just buy the block off plates and remove the whole AIS set up. Not only was I happy performance wise, but it made a LOT more room for plug changing.


Sent from my iPhone using Tapatalk

 

[FZ1inTX]

Or, remove the AIS system, take your stock plates, clean WELL and fill the holes with JB Weld. (http://www.998cc.org/forum/77580-post49.html) Fixed for under $5.00 and some of your time. Just be sure to cap off the hold in the airbox too.