250x keeps jumping timing
#1
250x keeps jumping timing
1987 250x runs great then dies. Every time, the timing is off. I reset it, but when turning the motor over after one full revolution the timing gear will be off 2 teeth, then 4 after the next rotation and so on. The cam chain is tight, but I can move the cam gear and chain without turning the crankshaft. If I turn the crankshaft the cam spins but does not keep correct time. What happened?
#2
250x keeps jumping timing
First make sure piston is TDC when setting timing. There are only a few reasons why this happens. 1st-piston wasnt @TDC. 2nd-chain is loose so it throws everything off, 3rd-cam gear is wrong size, 4th-chain tensioner is not working or bad. If you can turn the cam gear/chain with out the crank moving then I would guess either bad chain or bad tensioner. That shows loose chain.
#3
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