MY BUD IS GOING TO COLORADO IN OCTOBER ON A HUNT AND HE HAS A 400 2 STROKE EXPLORER, JUST WONDERING IF ANYONE HAS HAD HIGH ALLTITUDE PROBLEMS AND IS JETTING THE BEST WAY TO CORRECT? THANKS

 

When I initially bought my 2000 xplorer they told me they would set it up for high altitude riding. When operating the atv at altitudes from about 6000-8200 ft it ran like crap, fouling plugs and such. So I took it to another dealer who set it up right. The first dealer changed just the jets, whereas the second dealer changed clutch weights also which made all the difference. It will either make or break your buddies trip.

 

Dial-a-jets man, Dial-a-jets!

Clicky here

 

yes they will have to re-jet...

The altitude issue is less oxygen. Less oxygen requires less gas. It takes about 10 minutes to rejet an xplorer. I live at 5000 feet and run a 185 most of the time. When I ride in the mountains above 7500feet, I rejet to about a 170. If I knew I was going to be mainly at 10K feet or above, I might do a 160. It is OK to run richer (bigger number) at higher elevation although it might need run as well, BUT IT IS CRITICAL TO CHANGE BACK TO A HIGHER NUMBER (Richer) WHEN YOU RETURN TO YOUR FLATLANDS. Running in a lean condition (low number) is not good for your piston & head.