Jetting at 10,000 feet

I am traveling to Crested Butte Colorado in the beginning of August. I have a 2002 XR 650L with a Uni Filter and a FMF Q series exhaust. Can anyone recommend what jets to take. Or if anyone rides at 10,000 feet with that set up can you recommend the jets to start with. :)

I also live in Texas and ride in Colorado above 10k every summer. I have the 650R though, not the L. So I don't know the specific jet sizes you have. BUT! I can say that I jet my bike about 10% leaner for the altitude. For example here in Texas a 650' elev., I run the 175 jet. In Colorado for above 8000', I run a 160, and sometimes a 155 if I'm going to alpine loop over in Silverton, which is mostly above 10k.

The 650R has a handy jetting chart in the owner's manual, I don't know if the 650L has a chart like that or not, you might check that out.

Also, changing the main jet could require re-setting the needle position also, usually one position leaner for higher altitude, but I leave mine the same with good results. High altitude trails are generally slower riding, and in very thin air. This requires leaving the bike somewhat rich to avoid overheating problems. Jet it rich enough to avoid overheating, and lean enough to avoid sputtering and fouling. Good luck with it ! :)

I have a 97 and from what I know the bike has not changed I use a 160 main with a 55 pilot, stock needle snorkle removed Supertrapp IDS silencer,sparky,smog block off, no problems, I ride from 1500' to 12,000' and no worries, of course bike does loose some power at the higher elevations, but the XR torque is still there, I have never fouled a plug, the only thing that I do at high altitudes is turn the idle up a bit, tipical Honda reliabilty. Have fun. :)

10,000 feet, damn. Don't forget an oxygen supply :)

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