help please.

2 replies to this topic
  • fastcat71

Posted July 07, 2015 - 07:37 PM


Hello everyone haven't posted much on here but just picked up a 07 yz450f for cheap. Ran awesome when I test rode it got it home started up the next day. Now it will not fire. Have spark have gas. Valve clearance is in spec timing looks like the exhaust cam is a tooth off but it ran literally yesterday like a charm. Only thing that happened was added gas and it kicked back starting it but still ran decent. I'm going to check the flywheel key tomorrow after I borrow a puller. Any other insight on what could be wrong would be greatly appreciated. Thanks

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  • billygildark5007

Posted July 08, 2015 - 04:27 PM


Your timing chain may have skipped if it looks like it's a tooth off. When you have the flywheel off remove the chain and look for kinked links or bound links.

  • fastcat71

Posted July 08, 2015 - 06:08 PM


Good news re timed the cams and checked for a sheared key. Key wasn't sheared but when I put a new key in it and put flywheel back on my timing marks were perfect. So not sure if previous owner error or what. But got her all buttoned back up and tuned on the carb now she's running like a champ. Small hesitation down low but all is good and I can stop thinking I bought somebody else's problem

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