"Scotty" wrote
I, along with many of my friends have owned / ridden /
wrenched on many a Triumph / BSA / Norton and none of us
ever had ''Whitworth tools''.

yeah, those Whitworth Phillips head screws used to get
rounded pretty quick.

Y'all must be very young. By the 1960s Britian had adopted (BSS?) bolts using
US wrench sizes but with slightly different thread shapes. However, a few
Whitworth sizes were still found on accessories like carburettors, dampners and
dynamos. Six-point US box wrenches would fit all but a couple of them OK.