Coming on cam
Despairing of ever finding a side case points exhaust cam at anything like a reasonable cost and asking Engineering Lad to try out a special nut to replicate the taper needed to carry a points bob-weight advance and retard unit, all of a sudden, just such a cam became available. The cam is almost the same as the one used in the distributor motor but has a short nosing on the end to take the advance and retard unit taper.
With a twin engine such as a Triumph, the cams are inside the crankcase, a single engine such as the BSA B40 I had until recently, the cam can be changed without splitting the crankcase… thankfully so too can the cams on a unit 350/500cc Triumph engine.
It is a little more involved than a single cylinder engine, but Triumph’s own workshop manuals claim it is still quite a simple procedure. Yeah, right…
Unlike the 650cc pre-unit Triumph twin I’ve had since
