backfiring

[brad_300ex]

my 400ex is backfiring. what should i do. help. thanks

[Blake24]

running lean.......are you running any mods?? if so which ones.....:D :D :D :D

First you will need to let everyone know what has been done to your quad, and if any changes were just b4 the problem.

[brad_300ex]

everything is stock except a kandn air filter. thanks

[Rastus]

Did you rejet it when you put the filter on?
Also, did you check all the exhaust for leaks( there shouldnt be if its stock)

[brad_300ex]

the jetting is stock. i took off the exhaust from the engine to clean it and i put it back on and it backfires
thanks

[nakomis0]

Does the 300ex have the copper washer where the engine meets the exhaust, like the 400ex? If it does, you need to replace those when you swicth exhaust..or when you take it off to clean it I guess.

[rdmex]

i think u need a new exaust, u can still buy mine that fmf megamax II for 65 shipped
i will ship it to u for 65, let me know

[yamaha1470]

I have a question. My totally stock 400ex no mods no jetting changes just straight from honda sometimes makes a pop like 1 second after u shut it off. what is the cause of that? It only does it sometimes and doesnt do it while riding (or at least hasnt yet)

Thanks

[jleable]

sounds like my its overloaded with fuel when you shut it off and the heat made it ignite. Thats just a guess cause I dont know didly!

[yamaha1470]

any1 else know what it could be?