Mount Marks vernier pinion gears
Why? If your using one of Marks vernier pinion gears, you can fine tune your cam using the five key slots.
Each one gives a change of about 2 1/4 degrees.
Where to get? http://www.ccm-britain.co.uk/
Mark Says: Assuming you've followed the notes and came up with a timing figure based on the standard timing marks.
Make a note of this. Now make two more timing marks each side of the factory one with a marker pen.
Number them. 1 or 2. + or - . or whatever. Time the cam up on these marks and note the figures.
This will give you an idea of how the cam timing figures move.
My way:
If your "Calculated Cam Degree" from last page was 90 degree After TDC and you wish 100 degree After TDC.
Turn your engine to 90 degree ( your calculated cam degree ).
Now make a mark where your mark on the camwheel are.
Easy to remove and put back the cam in right place.
Remove the old pinion.
Turn your engine to the degree you want ie 100 After TDC.
Try to look which one of the 5 keyways would fit and put it on.
Now, cross your fingers and go back one page and make the "Calculated Cam Degree" again.
When you are satisfied, put on the cover and go back and do the "Calculated Cam Degree" again.
Can´t be done too many times.
Beware!!!
There is a risk if you don´t do this propery and the valves hits the piston!!!
Always on your own risk!!