sputtering

[pro-rider46]

my 450r is sputtering in the higher rpm range (7500-redline) and it is really starting to piss me off and i was told to replace the crush gasket on the header, so i did and it still sputters just as bad or even worse, the jetting is good and it seems to run fine with the jetting but can it be something more serious like bad timing or valve adjustment of something. i also put stp gas treatment in the gas in the tank just because i thought that it might have water in the gas. i puilled out the plug and it seemed to be a tan and black color without running it at all, it was also dry, is also blew compressed air through the carb and it still sputters really bad. sorry about the long post

any and i mean any help is greatly appreciated

[pro-rider46]

come on guys help me out here

[I wanna go FAST]

Do you have a pipe on the bike, and have you checked you air filter? i know when i piped my fourwheeler i had to rejet, and put a better filter on it plus i took off the airbox lid and it runs like a dream now.......

[Johnny B]

how do you know that your jetting is good? if you have too big of a main jet in it, it will sputter because too much fuel.

[TRX450RACER174]

Pull your plug and see how it looks, other than that pull the bowl and remove the jets and see if there is and debris in them. Do you have a pipe? your carb is might be dirty or check your a/f.

[pro-rider46]

i have good jetting, i have pulled the plug and it looked good but i replaced it anyways just cause i thought it might have been fouled. i pulled of the bowl, cleaned it with sea foam. the main and pilot are both cleaned. put some more sea foam in the top of the carb (where the needle is) also put some sea foam in the tank followed by some fresh 93. i cleaned the air filter also. i pulled the exhaust off awhile ago to polish the header and replaced the copper crush gasket. is there any other gaskets on the STOCK exhaust i need to replace. i have the stock exaust on it.the stock jetting with the lid works fine. could this be bad timing or a streched timing chain. maybe bad vavle clearences???

P.S. I have already reset my a/f ratio so its not that

thanks

[allstock]

did you check your pilot jet?

[pro-rider46]

yeah the pilot is clean with nothing in there

[honda4life72]

theres a gasket where the header hooks to the silencer

[pro-rider46]

do i need to replace it too or can i put hi temp gasket maker on it and have it work with out leaks

[I wanna go FAST]

i wrapped my header on my 450 with header tape and i have no leaks at all.. it looks a lil rediculous, but keeps heat down on the header and also stops any leaks from the header to the muffler!

[R_rocket]

if it doesn't run from 3/4 to w.o.t. then u need to put in a bigger main jet.

[400exrider707]

Definitely sounds like a jetting issue. Is your filter clean? I wouldn't put any sort of treatments in the gas tank personally, and to clean the carb... try carb cleaner, with the carb off the bike. A tan/black color is rich. The plug should be a light tan.

[pro-rider46]

i already put gas treatment in the gas and it doesnt do sh*t as normal. have you ever seen what seafoam is, it is not just a carb cleaner it treats gas aswell and works in diesels, fuel injected motors. so preety much anything with a motor can be used with sea foam. i dont think jetting is bad. i think it might be a bad stator.

[christ1647]

i know what your talking about have you tried to remove your big guns cdi and put stock back. Mine is like that with it in there. Dont know how to correct it ethier

[450rJam]

you keep dismissing the jetting ? what size is your main ?
you running the air box lid ?

with the k&n and the cam mod, your stock exhaust is putting a cork in your performance.
if your much larger than stock on the main jet your dumping too much fuel. it acts like a false rev limiter (just starts cutting out)
but runs ok up to 3/4 throttle.

[pro-rider46]

i have a 120 main (because the stock 118 broke) And the stock 48 pilot and i am running a lid till i get everything fixed, i took a look at my timing and valve clearences and they are dialed in. and my rev box is not in.

[450rJam]

it sure seems like a rich condition

you tried to run it with the lid off for testing ?

[christ1647]

my 06 trx450r wont run worth a damn with the lid off.

[pro-rider46]

yeah i ran no lid and it absolutely sucked jsut bogged real bad. why would it seem like a rich condition, if any thing it is real lean.

i singled it out and the only thing that it can be is the stator because its not jetting, its carb is clean, i dont have the rev box on and the timing and valve clearences are good also. the only thing left that i can think of would be the stator.:(