Intake Cam profile question 03 YZ450

2 replies to this topic
  • shortburb

Posted September 29, 2008 - 08:27 PM


Iv been having some hard starting issues lately and havent checked the valves in a while and all my intakes are tight...No biggie Ill get some shims tomorrow...

While checking valves I noticed all 3 intake lobes on the cam (look like they) engage at 3 different times...the lobes are 'twisted' slightly in relation to each other. The bike runs great and makes power but to me having all 3 valves open simultaneously would create a deeper vacuum for more fuel....

Know what I mean?

Is this how it is or has my cam somehow 'twisted'? The cam is in great shape not a mark on it no heat marks that I can see...nothing...

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  • grayracer513

Posted September 29, 2008 - 09:13 PM


The outer lobes are aligned with each other, and the center lobe is rotated slightly to compensate for the fact that the center valve enters the head at a slightly different angle than the other two.

  • shortburb

Posted September 30, 2008 - 06:19 AM


Thank You

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