need help

[jimerson132]

i have a 05 450r and when i let off the gas i pops real bad know some people told me my valves are to tight? could that be it. and i have a tmm race pipe on it and its perty much stock other than that anybody can help me ill take the advise. thanks

[Brad_9876]

Mine did this real bad also when I had a pipe put on, check and make sure the copper crush gasket is in the headpipe. This was my problem.

[d3ktrix]

Did u rejet the carb when you out the exhaust on?
Did you remove the air box lid?

[jimerson132]

ya it was wrong size jet i put a 171 in it and it runs fine know...i had someone jet it and they didnt know what they were doing