Possible plugged jet

I just bought a 2003 WR 450. When I was at the guys house riding it, it ran fine with no problems, but ever since I transported home in my truck which was about a 3 hour drive, it started to run like crap. When I have the choke pulled out, it runs like a dream, very steady idle, no problems at all. If it take the choke off, it has a very unstable Idle, i have to crank up the idle speed so it will stay running but after running it for a while once the bike gets nice and hot it idles higher, but still not very steady. This leads me to think that it is the carb, i have cleaned it once but maybe I missed something. i have had friends tell me it might be a plugged pilot jet but I just want to get some other opinions. I also plan on changing the spark plug.

Try adjusting the pilot screw first, Never hurts to throw in a new pilot jet i wouldn't recommend cleaning a pilot jet as new ones are very cheap!

Edited by PelvicThruster

Look in the tank with a flashlight, for any debris.

If there is debris, you will need to clean the tank, filter, and replace the fuel line.


Pull the pilot jet out and REPLACE IT. Don't try and clean it.


Pull the carb vent hoses (not the over flow) up and over the carb.

Best to even filter them, as that is the worst source of dirt into the carb.

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