Stalling problem

I have a 2003 YZF450 that usually runs great. I raced a Hare scrambles yesterday and had a hard time keeping it running. I have a GYTR flywheel that helps but for some reason it would backfire and then stall in the slower sections. It was around 45 degrees here yesterday. I am thinking that it was either too lean or the idle too low.

Anyone else experience this problem?

Thanks,

Paul

If you have not already, you might want to bump the pilot to a 48 and turn your idle up 1/4 turn when your doing a lot of slow stuff. Make sure you use your fuel screw to fine tune it all.

A 48 pilot is too big for a 03. They come stock with a 42.

It sounds like it was a little cold outside and running a bit lean. I would try to turn out the fuel screw and see if the popping goes away. If you have to turn the screw out more than 3 turns to make it run right, then you should replace the pilot jet with the next bigger jet (a 45).

Remember, a properly jetted YZF will have some (not a lot) popping on deceleration.

I rode my 03 this past Sunday (50 deg), I had to adjust the air screw out a little and it ran fine.

Fine tune your fuel screw and if there is still a problem then try adjusting your idle up a little bit...I'll do that when I'm running a HS on tight trails and it helps quite a bit.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now