Initial timing and va lve piston check:
This is very important since when cams are advanced the piston clearance reduces dramatically.
And Lobe re=design can effectively advance the valve opening.
Set Intake and exhaust cams at initial LCs as indicated by provider`s set up instructions, and lash
By running the .050 plastic wire-tie between the Intake valve & piston, and .100 (or .080 ) on
the Exhaust side you can check if there is any interference and see that you have adequate
clearance between piston & valve. If by turning motor over by hand you feel some interferance
using a .050 thick wire-tie, (or .100 on Exhaust) but the motor continues to roll through, you are
at the limit! YOU MUST ROLL THE MOTOR OVER OVER BOTH FORWARDS &
BACKWARDS TO BE SURE THERE IS CLEARANCE AT THE LIMITS!! REMEMBER,
WHEN OFF THROTTLE THE CHAIN TENSION REVERSES!!
If it locks up, retard the cam(intake side, you would advance the exhaust cam a degree or more to
get more clearance) a degree (or a couple of degrees) and try again until the clearance is found.
I suggest as a test to find this limit, you advance the intake cam until you do, and permanently
mark that point on the cam cap. That will be the point where the cam must NOT be advanced
past. Then do the same with the exhaust only retarding it until the limit is found.
Timing initially is dependant on design of cam lobe. Aggressive large duration cams will be more
retarded.(intake) and advanced (exhaust) because of ramp & valve lift.
Tighten and instal lock nut on intake and bolt through sprocket and cam nut. Inspect carefully.
Roll the crankover by hand to verify timing.
When the intake cam is at the limit, or LC setting whichever is less advanced. You are there!