03' xr120 help idle prob

I just finished the BBR 120 kit on my wifes xr100 and the sucker wont idle :bonk:

It will start if I give it 1/8 to 1/4 throttle and run fine untill I let the throttle go. I did notice I had no spark and wiggled some wires on the harness and it made a spark. So how do I test the coil? I have a stock control unit that I tried and it didnt change anything. I have a tryed a 38 pilot jet and a 48 both brand new and adjusted the air screw all over the place it made no difference. It also seems to get hot fast, might be wrong there. Any way someone give me another way to check something I am out of Ideas. :thumbsup:

no spark?.. at low rpm's?.. how do you start it then?, and when it does spark is ti a nice crisp hot spark or kinda a sluggish spark.. did you check your valve clearence? or how about your cam timing?

Spark looks ok but nothing like my jet ski does, Valve clearence is set to spec .003 cam timeing I have no idea I just lined up the dots one the cam and the flywheel to spec. I can start it just by 1/8 throttle and it revs up grate just wont idle.

Plugged pilot, air leak, bad ground, bad plug cap.

Well I can rule out pilot being pluged its new. Air leak from Cylender head or carb side? I'll go get a plug cap today just because they are cheap, and where is the ground wire?

Called BBR they said turn the idle screw in a bit and what do ya know works like a champ now. So FYI for all the guys doing the 120 bbr kit you need to adjust the idle screw in a 1/2 turn or so.

What carb? stock, 200x, mikuni?

What carb? stock, 200x, mikuni?

Stock carb

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