YFZ won't rev
 

I've had my 450 for 11 day now and it ran perfect but yesterday i went out to take a ride and it cuts out on the top end, it almost feels like the rev limiter is kicking in but it isn't reving as high as it did before. What could be causing this all of the sudden?

YFZ won't rev
 

stuck choke? Bad gas? Not enough oil? Fouled plug? Horribly off jetting? All possibilties.

-Nick

YFZ won't rev
 

I would take it back and let them fix it.

YFZ won't rev
 

id hook mine upside down on a chain, and let it fall, try it, itll prolly work, be safe, have fun!

YFZ won't rev
 

its probably some stupid parking brake limiter. Yamaha finds ways of putting them on most of their products. See that its adjusted properly if it has one. ..

Or when its doing it, see if you can jiggle the lever and hold on at the same time.

YFZ won't rev
 

I don't think the 450 has a parking brake limiter does it? ?

I would take it back to the dealer and have them fix it under warranty, whatever is causing it.

RR1

YFZ won't rev
 

Did you find out what was causing it.....I've got the same problem.thanks.

YFZ won't rev
 

450 does have a parkin brake rev limiter!

YFZ won't rev
 

its a Yamaha

YFZ won't rev
 

i took my carb apart about 8 times one night cleaning and changing jets cause it was cutting out like your explaining. there were about 13 other people waiting for me so we could leave for riding trip. it turned out to be the parking brake. D@MN the parking brake, i cut the wires on mine.