08 450f Timing Problems

5 replies to this topic
  • fixxor

Posted May 11, 2013 - 11:47 AM


Hello, my 08 450f started getting hard to start. Meaning not compression when kicking, just it would not start like it used to. I had to kick it like 30 times for it to start. When it finally did it ran fine. I did this 2 times and rode it for a little bit. Now I tore it down to check timing and valve clearance and I am finding this. Cams are WAY off, I did not think it could even run with them like this? Am I missing something? Now here are the questions, I know I need to replace the timing chain and tensioner but..

What damage could have been done?
What else should I do besides the chain and tensioner?

Here are some pictures to help. I would really appreciate some feedback.



  • mpmoto

Posted May 11, 2013 - 06:43 PM


was the engine noisy ? like valves tapping piston ?

fit a new chain and a new tensioner would be a good idea too. one it's all fitted and timing set, check the position on the lobes on the other side.

you want the point end of inlet lobe at approx 10o'clock

you want the point end of exhaust lobe at approx 2o'clock

cam gets have been known to spin on the camshaft giving incorrect timing

  • mpmoto

Posted May 11, 2013 - 06:45 PM


I forgot to add, you might want to check the timing chain gear on the crank for wear.

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  • fixxor

Posted May 11, 2013 - 08:59 PM


Thanks for the reply. The engine sounded the same to me. When I change the chain I believe I have to take off the cams. Can I check to see if anything was damaged then?

  • mpmoto

Posted May 12, 2013 - 01:13 AM


you wouldn't know unless u took head off. you would know if the valves were tapping piston as it would of been very noisy.

  • fixxor

Posted May 12, 2013 - 07:59 AM


Ok. Thank you.

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