ok I just purchased a yfz 450 and it was supposed to be perfect well guess what it hs issues i was wondering if someone could answer some questions for me....
there is a switch in the throttle housing on the handle bars that tell something when the the throttle is closed. I have done a bunch of checking and the motor has not spark at idle if i take the slack out of the throttle (away from the switch) it will start and idle just fine....any ideas?

Not exactly sure what it does, give me a day to look it up and see.

mine was doing the same thing. splice the 2 wires together.

i think its the T.O.R.S SWITCH LOTS OF YAMIS HAVE IT. BASICLY YOU HAVE 2 SWITCHES 1 AT THE THUMB THROTTLE AND 1 AT THE CARB. ONLY 1 IS OPEN AT A TIME SO IF IT DETECTS BOTH OPEN AT ONCE IT LIMITS RPM TO 2500-3000 ITS A SAFETY FEATURE YOU CAN BYPASS IT BUT I MYSELF WOULDNT!!! ALOT OF TIMES YOU JUST NEED TO SET THE CABLE SLACK AT BOTH ENDS PER THE MANUAL

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