YZ426F jetting @ 5000'

Just bought a YZ426F with an aftermarket Dirt Squirt exhaust pipe. I know the stock jetting has been changed, but is most likely set up for sea level. What will happen if I don't rejet for 5000'?

If it is jetted correctly for sea level and the temp is close to the same as it is at 5000', the bike will run rich.

It will be much hotter. Probably in the high 90's. I'm guessing it will be ok for a few rides in the dunes...

Jetting is extremely easy to change. If you are going up in elevation just go buy the next couple jets below the one you currently have and bring them with you (might want to bring an extra spark plug too just incase). Ride your bike around a little bit with each jet in and figure out where it's running the best.

That's usually my simple approuch for a 4stroke though. Although, most of the time going from 1500 ft where i live to the coast with different air conditions as well, i'm fine with the same jetting.

I am at 5000 feet and Im At a 158 main, 42 pilot and 2nd slot on the needle...

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