HEADS UP!!!

Site upgrade in progress... Core site functions are working, but some non-critical features/functions will be temporarily unavailable while we work to restore them over the next couple of weeks.

Please post any bugs you encounter, but before you do, check to see if it's already listed.

Thanks for your patience while we work to improve the community.

Sign in to follow this  
Followers 0
kizzle426

For all who deal with jetting...

3 posts in this topic

I got out to the track on Sunday...all fired up to race...then my bike doesn't start. I was so pissed. It started perfect a few days prior. When we did get it running it kept gunkin the plugs. We took it home ('02 yz426)and started fooling with the carbeurator. We moved the clip up one groove on the needle. Then I turned the pilot screw about 2 1/8 turns out from closed. We tested it out and it started and ran great...there were a few pops on decelleration at first but those stopped after it was good and warm. I'm writing(typing) this just to see if this worked for anyone else. Also I'm wondering if going up one groove on the needle from stock will make it too lean. just let me know. I know jetting changes with temperature and humidity so it might only be something I can know. Also, what are some long term bad effects of running to lean. let me know guys, but like I said it seems to be running better than it has yet. Thanks in advance for all your replies.

Share this post


Link to post
Share on other sites

If I'm not mistaken, running too lean will caue your engine to run too hot which then may cause premature wear. I don't think only moving the clip up one position could cause a dramatic problem... specially if the bike ran too rich before.

Again, I'm not the guru here but if I'm not mistaken, the fuel goes though the main jet before going through the needle jet. The way I see it, bigger main with needle down(clip up) or smaller main with needle up (clip down) are approximately equivalent when at mid throttle... I mean, it's not just the needle..

If the bike runs better, can't be bad...

Now let's hear the gurus :naughty:

Share this post


Link to post
Share on other sites

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
Sign in to follow this  
Followers 0