late 750 on the right, not 850 as the DS scroll is not correct for '70's made 850 cam.
Why?i beg to differ sir.
Why?
every combat i have torn down had scrolled cams. i am not saying there were some with the non scrolled cams but i have not seen one.
Here's one...
Out of a Combat I'm rebuilding. No stampings to show it's a 2S but it's higher lift than std. Everything else definitely Combat spec.
SS stamped next to slinger ring IS the combat marking
Are you certain they we combat cams. Many of the combat engines were rebuilt with standard Commando cams which would have scrolled bearing area. The original combat cams shown in the parts book dwg as not scrolled and all the manuals warn not to use unscrolled camshafts with unscrolled bushes. The lobes on a combat when side by side with a standard Commando camshaft are very appearent.every combat i have torn down had scrolled cams. i am not saying there were some with the non scrolled cams but i have not seen one.
FWIWWhy, as LAB has said, but there are differences, the DS camshaft scroll for the 850 has the scroll break the end on 850 cams, when the 06.1084 was re-introduced the drawing was changed for the scroll to be correct for 850, this was changed in July '74 (amd 10) back to the original scroll end, so one cam fits all. The drawing has no change to the breather portion at all during all 17 amendments.
Many owners note that the when they fit a current cam in the 850 DS case and look in the oil hole, it the drilling enters the chamber at the end of the cam not onto the cam itself, as per the early cams, some leave as is, some nick the metal away at the old timed drive chamfered slots at the cam to aid the oil to enter the scroll.
All the cams with marking on the end, that I have seen, were aftermarket cams...like 2S, 4S, 7S or welded reground and end marked. Plenty of other hot rod cams were marked on the shaft area.Good Lord - so it is!
All the others I've seen had it stamped on the side of the lobe or on the end of the cam - never even thought to look there
All my OEM combat cams were plain shaft.?every combat i have torn down had scrolled cams. i am not saying there were some with the non scrolled cams but i have not seen one.
The 500-600-650 small barrel are in another part of the shop. Most of these large barrel desaxe engines were bought at an economical price. There are more, but mostly in rolling chassis basket cases, and mostly as research assets/subjects. I try but often fail to keep 3 Nortons road worthy. One each garden gate, featherbed, and a commando. Plus one modern bike(ducati) and a BSA A-10Wow. That’s an impressive number of motors.