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Discussion Starter · #1 ·
Not a question but this may save some folks from hours of head scratching.
Been working on this quad for friends. (2000 big bear 400 4x4) It started one day - ran fine - moved indoors - the following day would not start. Has spark / fuel / great compression.
Probed everything out and all ignition components were ohmed out within spec.
(charge coil . pickup coil - coil - voltage regulator - stator) All good.
Compression good. Valve clearance good.
Checked timing and it appeared to jump - cam sprocket mark not lined up to the mark in the head - flywheel lined up to "T" (approx 3 teeth beyond TDC.)
Pulled the self adjuster - repositioned the cam to TDC thinking that was that.
Still no start.
After hours of trying to find anything - even close - on many forums - and the thought of spending a few hundred on a CDI I can't determine if bad . . . . Wondered if it was possible for the flywheel key to shear. Answer - it is.
Pulled flywheel - replaced key and retimed to TDC.
Problem solved.
Oh and check this first before you do an oil change and waste all the new oil you just put in. Hope this helps some of you out there.
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