if your happy with it set to what ever it is,index the cam and sprocket together with neat sharp prick punch marks so you can reinstall it the same if you ever take it apart,or go the extra mile and have an engineering shop drill another pair of holes about 180 degrees away from the factory ones but say 5 or whatever crank degrees you want different from the tooth(i dont like slotted cam sprocket holes),have it stamped say +5 or what ever it is on the side that faces the points and factory cam marks,if you reverse the sprocket the cam will be retarded that amount!five crank degrees is only two point five camshaft degrees,takes some good accuracy to square it away,a lot of vehicle engines through the smog years had the same cam but the key way or timing marks were moved to retard or advance the cam,this is how myths started about early and late cams etc being better,it was only the timing,some makes even did alter the lobes,mix that with the wrong sprockets marked differently and you can see how guys have bad results with cam swaps?if you expect proper performance this is why you must degree your cam in automobile engines.
be sure to check your piston to valve clearance if you alter the cam timing,the valves come closest to the piston during overlap,you can crush plasticene in the engine and have a look,or using soft springs on the valves(you only have to set up one cylinder with valves and light springs,leave all the other valves out) rotate the engine to overlap,then measure how much further you can push the valves down by hand untill they foul the piston,both valves are open a little here,this is done so at a certain rpm some new fuel flushes the old burnt out,its called scavenging(degrees of overlap),mild cams have less,wild cams have more,wild cams dont idle well because of it.
thats trying to keep it quick and dirty 70CB750,dont you ever change your avatar,i dig it!
