750 Combat setting up camshaft timing

I've got the Norris RX camshaft in the engine - engine without head in the frame. Next is checking the setting camshaft timing. Will be getting a .500 range dial indicator, extensions and magetic stand at the end of this month.
Question: splitting the difference in the open/close degrees from the Norris spec sheet max lift for intake is at 104 degrees ATDC and exhaust at 76 degrees ABDC. Would you agree this is a good starting point for checking camshaft timing? Plan is to check directly on the lifters. This method eliminates the question of start of openning differences - at 0.020 tappet clearance versus valve lift from the start of the quieting ramp.

Norris RX timing spec at 0.020" tappet clearance
Intake open 54 degrees BTDC close 82 degrees ABDC
Exhaust open 82 degrees BBDC close 54 degrees ATDC

That's the way I'll do my Norris D cam, set crank to max lift degree's, 104 ATDC
then set cam intake lobe peak there and nip up and see if everything clears then how it runs. More broad range power advancing and more peak power by retarding cam. Even half a degree can be felts or measured on dyno on potent pressing limit engines.

"More broad range power advancing and more peak power by retarding cam"

Steve,

This helps..Thanks. For a bit more broad power maybe I will advance a bit if possible. I know 2.5 degrees per gear tooth, so that might be too much. Do you know a source for offset woodruff keys?

Several places make vernier camshaft gears, I believe they are .5 degree increments.

Norris RX timing spec at 0.020" tappet clearance
Intake open 54 degrees BTDC close 82 degrees ABDC
Exhaust open 82 degrees BBDC close 54 degrees ATDC[/quote]


WHY , Well Then ; THATS Symetrical Timing , just like a Triumph Bonneville . :mrgreen:
Cant be too hard to GET RIGHT .

CHECKING on the overlap , IF youve set the clearances even , theoretically , It Will let go or grip a feeler guage
AT exactly the SAME degrees off T.D.C. on the oposeing cam flanks .Thats my theory and im sticking to it . :lol:

NOW the little TEETH give 15 degrees , and the chain teeth 15 , so one minus the other is 5 , or 2 1/2 if youre at half speed

SO , before lashing out for a five million dollar sprocket , and a new other one , and drive cog , Just to keep them Matched ,
setting up the cabboodle , if it lands 2 or 3 degrees early , if its a street bike , youre not going to loose any sleep , in fact
it might save fitting a new clutch too , as you might not need to slide it all the time getting underway . :lol: 8)