I have been sitting on the report for a week. I will not be releasing the results until cam and followers have gone back to be tested by the suppliers. Let me dispel a few myths first. 4,000, 1200, 1500 , 26,000 miles before failure. They are the ones I know about. Why the disparity? Because I had the NASA coatings applied to both the cam and followers when the engine was rebuilt. The only reason my cam lasted so long was because of the coating. This was confirmed by the metallurgist. I am an absolute believer in the use of appropriate coatings on our old clunkers. Living, confirmed proof. During the rebuild, the cam and followers were liberally coated with the appropriate lubricant. To suggest that the damage occurred early due to incorrect lubrication is plain silly in my case as the motor would not have lasted as long as it did if it was damaged early. The engine builder is very experienced with Nortons. I was speaking to the boys at CIC Coatings yesterday, but Paul was quite coy about the actual coating applied. Trade secret apparently, but I will try to weasel it out of him for the edification of all.
I run Penrite 20/50 motorcycle oil with the correct zinc additive. The metallurgist agreed that the oil choice was appropriate. Oil changes were at 1000 miles, except on my big trip where the mileage doubled without a change. The engine was very clean inside on disassembly. The crank had to be reground and main bearings replaced.
All in all, a very disturbing report with ramifications for all. My reference to Andover Norton as the supplier of the cam was incorrect. The PW3 was supplied by Mick Hemmings about two and a half years ago.