QUESTION ENGINE/CYLINDER HEAD
Hi I just bought a low mileage '72 Combat Commando that has factory original engine specifications and am planning some engine mods for improved reliability. I see that you have various lengths of pushrods available. Could you tell me what length pushrods of yours would be best for a standard Combat engine?
Whilst the Combat had a higher cam lift and material removed from the head Norton's did not make a special pushrod for this engine, there are a lot of factors that affect the rocker geometry and I feel the only way to improve upon what you have is to do a dry build and watch it working, setting the rocker adjuster to sweep more or less evenly across the valve tip rather than merely from the center to the edge, or visa versa. We do stock a number of different length pushrods and also things like mushroom tappet adjusters and lash caps, (buckets to sit on the end of the stem thereby lengthening the valve) and we also do slightly shorter valves. Hope this helps.