Cam identification

[dermothalcyon]

Hi all. I have a 1938 VG engine in my bike that has been fitted with a single lobe cam. Is there any way to tell if it has been ground with the quieting ramp? Should I stick with the 0.002" clearance?

[Roger Gwynn]

The only way is to use a dial gauge to see if it opens quickly or over many degrees. If you have an earlier cam you can compare the rate of opening.

[david.anderson]

If one of the standard cams has been fitted (rather than one of the competition cams) they can be identified. The early single lobe camshaft is cast steel, (the casting, rather than a machined face is visible on the innermost face of the cam ) the later ramp cam is a forging and can be identified by the horizontal hole through the lobe of the cam and the innermost face is machined.
Edit
From memory the early cam lifts the first .010" over about 25-30 degrees of engine rotation. The ramp cam would be 60-70 degrees for the initial .010" lift
David