2001 YZ426

Let me start by saying I love my bike but it has been very tempermental. I had a hard time getting it to run right and finally did after tweaking the carb with the jet needle and the pilot screw and switching to 110 octane fuel. The last two times out its not been running right again. Pulled the carb and cleaned haven't put it back in yet but hopefully it will be ok again. Now to my real question. I live and ride in south Florida, a buddy and I are going out to Colorado Springs for a week of trail riding in Sept. What do I need to do to the bike so it will be even half way reliable? Right now its not reliable at sea level let alone at 8000 - 14000 ft elevation.



The JD jetting kit would be your best option. I live in COS and never had the bike running right until I bought the kit. I have mine set for 6000-9000 feet and it runs well (don't quote me but I think its a 56 main jet, 3rd clip position and 2.5 turns out on the air screw). I can pick up the directions tonight and let you know for sure.

I have an 02 426 and have had the same problems. The Ty Davis crew couldn't even figure it out at the last WORCS race (its not like they were going to spend a lot of time on it though). They said 4 strokes shouldn't be that temperamental but mine sure is.

Hope you have a good time in the mountains.

Thanks for the info. If you can the exact directions would be very helpfull. If yours runs good with those settings theres no reason why mine shouldn't. Thanks again.

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