Hard Starting? FYI........

Thought I'd pass this info on in the event it might benefit others. Have an '03 steel framed WR450, and the thing has been rock solid reliable (did starter clutch upgrade early on) since it was new. Always started easily, until recently when it took more than the usual effort, both hot or cold. The bike also seemed to boil coolant more easily on technical singletrack, but I thought it might just be my imagination.

Checked the valves and compression, installed new plug, but nothing had an effect. Pulled the carb off to give it a good cleaning and blowout, but everything looked good. On a whim I pulled out the choke knob and spun it with my fingers and found that the shaft was slightly bent, although it still functioned properly as far as opening and closing the choke circuit goes.

Turns out the slight bend in the shaft was enough to create a small vacuum leak at the shaft seal boot. $15 for a new choke plunger assy and the bike starts and runs like a top again.

FYI - If you have an Acerbis desert tank, be aware that any low speed tip over on the left side can cause this problem. A lobe of the tank hangs down close over the choke knob, and a good bump is all it takes to push the lobe in to bend the choke shaft.

Easy to fix, but not easy to find.......


silly little problems like that can be frustrating

My friend had a aftermarket gas tank vent malfunction and wouldn't let air in the tank.He was smart enough to diagnose it pretty quickly.But I dont think I would have

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