It has been my limited experience that it is much easier (at least with motorcycles that do not use a common intake manifold) to determine a reasonably accurate intake valve closing number with the the throttle plate open (no intake restriction) in comparison to when the throttle plate is closed. Is this been the experience of others as well? I have attached a couple of examples.

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James the valve timing in the note section are they the specs or what you feel the scope capture is telling you?

Spence, those numbers in the notes are the correct cam timing specs. That is how I determined the cam timing was out. I have just found when the intake is not open when doing an ICCT it is really hard to see the intake closing point.