2014 YZ450F pops

[freestyle316]

I bought a new 2014 YZ450f and put a FMF slip-on on it and it has popped ever since. I have GYTR tuner and I have added full all across the board and yet it still pops. It only pops when I let off the gas. I've fought with this problem since I bought it. Bike runs great just the popping is very annoying. Do I need to add more fuel? Timing?  Please help.

[William1]

The stock muffer (which was/is excellent) miuffled the pops you now hear.

 

You can ensure you have no leaks by holding a wet towel over the end of the muffler and listen for hissing.

[Dexter42]

Popping can be related to many things such as, bad gas, dirty air filter, bad plug, air leak somewhere, even electrical. But since you just put a pipe on I would think it has to do with your mapping. I am fairly new at FI so I couldn't tell you exactly what to map but I have searched for maps and there is plenty of them out there. I know there's a full thread of them here on TT and yamaha has some on there website, have you tried any of them??

[freestyle316]

I have tried all the maps that motocross action showed on their website with no luck. The best luck I've had was adding +5 fuel all across the board with stock timing but it still pops. I put a new air filter on after every ride. I run T4 vp fuel.

[Dexter42]

...

Edited July 31, 2014 by Dexter42

[keenxxx]

The last 2 bikes that came through our shop "popping" on decel were from exhaust leaks. The first bike was leaking between the slip-on and mid-pipe. A coat of copper silicone sealed the joint and eliminated the popping. The next bike developed the popping after an FMF Powerbomb was installed. Owner installed the pipe but left out the copper washer... It didn't Sound like an exhaust leak aside for the popping. New copper washer and all was well.

Edited July 31, 2014 by keenxxx