Need Hot Start to start when engine is cold.

I know this has been asked before and I just can't find a definite answer with the search .So here goes.

I have an '02 WR 250F with stock jetting -except the fuel screw.I have it at 1-1/4 turn from seated.I have never taken the carburetor apart, but I assume all else is stock.

I recently traded for a Powercore 4 muffler , from an FMF Q.The header is a powerbomb SX.

Before I broke my collarbone and traded the Q , I did notice the bike was harder to start from earlier in the year,it is the same with the 4 ,but more pronounced.The weather here in Missouri has been abnormally HOT(could that be the problem?)

I'm sure the jetting is too rich.Do you have any suggestions for my jetting changes?

Thank You for any input. Mike

Try asking the guys on the YZ250F/WR250F forum. They have more experience then us with jetting the 250's. :)

It's a pretty simple issue really. If you need to use the Hot Start to start a cold engine, then your pilot jetting is way too rich, thus the need for an air injection to even things out. You can begin by closing the fuel screw and opening it 1/4 of a turn and see if that helps. Make adjustments out no more than 1 1/2 turns (in a rich condition). If this does not help consider opening the carb and droping the jetting 2 sizes.

Bonzai :)

You checked out the air filter?,if you need to lean a cold motor to start it it is perhaps to rich to start with! :)

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