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Question for all you carburetor experts:

I am running the stock Jetting and have done the BK Mod. The bike runs great and starts 1-2 kick. What I have noticed recently is a little backfire on decel. And when I shut the motor down I get a Burp from within the pipe it sounds like. Almost like you would exhale after a hard exercise. :):D

Question: Will playing with the fuel screw help correct this. Or should I maybe look into a larger pilot jet.

Thanks in advance for the help,

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I am not sure about the burp, however the fuel screw will eliminate the popping on decel. Thurn it out to richen it up a bit. Some popping on decel actually gives better throttle response. Make sure the bike is thoroughly warmed up before making any changes. If you dont have a manual check out Motoman393's site as it has an online manual. Just follow the manual to the letter and it will go fine. remember to only make one change at a time to reduce the variables. Good luck

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If it feels good then I wouldn't worry about the minor popping or the soft backfire when you turn it off (mine does this too).

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The short answer is yes. The strange issue is the burp...That normally happens when gasses are not passing fully through the exhaust system and are ignited in the can or the headpipe with the rush of air entering the chamber when the engine is shut down....Basically loading up. Check your entire exhaust system for leaks. You may very well have a connection siphoning air into the system causing this problem. I've seen this twice before where removing and re-seating the entire exhaust system cleared it up.

Bonzai :)

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Hey yamakazee, thanks for the tip!!!!!!I've fought with my jetting for week to get rid of that darn popping.

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