450 timing question

3 replies to this topic
  • thumpyz

Posted March 07, 2008 - 01:17 PM


I was checking my valves, and when I put the motor at tdc my cam index marks and the "I" on the rotor dont jive. when I put it all back together, i have the "I" mark lined up and my cam index marks are lined up as well. The problem is that when i install my tensioner the "I" mark moves forward. Do I need to adjust everything so when it I tighten the tensioner everything lines up? I would think so, but I would like some experienced opinions as well. The "I" mark is about an eighth of an inch forwad of the alignment mark. Deos anybody think this has screwed up my valves? thanks

  • grayracer513

Posted March 07, 2008 - 01:28 PM


One more time. When checking the timing, start with the cams and crank about 5-10 degrees before TDC. Roll everything backward slightly to achieve this, if necessary. Then carefully roll the crank forward to TDC and check the timing. This pulls the front and top runs of chain tight, as they are when the bike runs. Then install the tensioner and recheck it.

What you see there is normal. The crank can move perhaps 20 degrees without moving a cam when the tensioner is out, and it takes almost no effort at all to move the crank when it's near TDC or BDC.

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  • thumpyz

Posted March 07, 2008 - 01:37 PM


:thumbsup: :eek: :D Why cant it just say that in the manual?

  • grayracer513

Posted March 07, 2008 - 01:39 PM


I think it does, but it's in "Engrish", so it can be a little unclear sometimes.

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