Those of you with mid-sixties Norton, Matchless and AJS motorcycles will recognise the three hole hub cover which fits on the speedo drive side of the rear wheel. There are three grey or black grommets which blank the holes, once you’ve tightened the sleeve nuts. The hub cover part numbers are 06-7711, or 06.7711 or NM18348, depending on your spares list.

My original time-served hub cover

Having had the wheels on my 1966 Matchless G12 rebuilt with new stainless steel rims and spokes, it would have been a shame to refit the rather bruised old hub cover. I’d have preferred a matt one, similar to the finish on the one that came off. These days, shiny is the only option.

You would think it would be an easy swap out…but no.

If you decide to replace yours, take the old one and place it on a flat surface. Measure, with an engineer’s steel rule, the distance from the flat surface to the inside (or outside if you prefer) of the centre hole; my pictures will show you what I mean.

Mine measured 15mm to the inside surface but when I bought a new one from Andover, there was a 3mm gap between the outer edge of the hub cover and the hub itself; no way would it fit. I measured the offset distance and found it was just 12mm.

The Andover hub cover which would not fit

Andover believed their part was right so I contacted Norvil and AMC Classic Spares. Theirs measured 16.4 and 15mm respectively; I think the Norvil one was probably on the tolerance limit. Andover did refund me and I bought one from AMC Classic Spares which fitted immediately.