Interesting statement in the article:
"The earliest Commandos were built at the old Matchless factory in Plumstead, South London. With the Plumstead site slated for redevelopment, assembly moved to a new facility in Andover, Hampshire (on the famous Thruxton circuit), while engine manufacture went to the Villiers factory in Wolverhampton, West Midlands.
This presented an opportunity to tidy up the Commando engine. Principally, contact breaker points were moved from a chain-driven jackshaft behind the cylinders (where the magneto had been on the 750 Atlas) to the end of the camshaft—simpler and less prone to wear. The new Wolverhampton motor became the 20M3S, while production of the old 20M3 “jackshaft” engine stayed temporarily at Plumstead pending the plant’s closure. (The numbering scheme works like this: the 750 twin engine was Norton’s Model 20, and the Commando engine the Mark III version; hence 20M3.)"
However this part , while not about "R", Does not seem correct:
"The
S made a radical styling statement. Its
five-inch headlight wore a chrome “halo” attached to a special top triple tree. "
HiRider was 5"
Also Is gortnippers's pix of "an R" or
muddygoggles "R"???