450X top speed sputter

i was rolling down the orad in 5. long straight hit full throttle-- wow it flies. but it started sputtering. like go, pause, go, pause, only enough to notice, so i brought the speed down and it was gone. i didnt like it though for a new bike :naughty: any ideas? about 120 mile on, NO maintnance yet.

Sounds like the rev limitter, or severely bad jetting. If you're topped in 5th, at wide open, seriously, then I'd say limitter.

It sounds like the rev limiter. The 450X has more than enough power to pull to the rev limiter in 5th.

I just switched to taller gearing on my 450X. A tooth bigger on the front (14) and 1 less on the back(50). First doesn't need to be that low on this bike. Top speed should be about 90 with this gearing.


Not the rev limiter. even after the X hits the rev limiter it DOES NOT SHUTTER,SPUTTER,OR COUGH, it just "softens" and keeps right on going. I would look more at the ignition, or valves.

try unhooking the pink wire to see if it goes away, that will let you rev past the point of the limiter

but it started sputtering. like go, pause, go, pause, only enough to notice
Hmm... ironic? (nevermind)

It's the Rev limiter. It's subtle, but effective and I don't like it! :naughty::D

btw - Craz - Love the signature! :naughty:

thanks guys, i dont know what it is but im going with most of you and saying the rev limiter. ill do the gearing change. im alos thinking about throwing another grand at the dealer for the ice cube bore kit. bring her up to a 500 cc, well 498 if you want to get down to it. im sure the gearing will be way to small for that. so ill have to do something about it. im working now to get the money, but when i get it its back to the racing for me. just want to make my baby bettet then any other before i throw her at the gncc's, and enduros. and other mods you guys no of that would help bring the bike up in performance, or just things that would help. if you have something to say about the sputtering go with that too. thanks

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