Third Time Lucky

Will this third BSA side-valve single measure up to the first one? Should you ever go back? Yes, of course you should if it provides a spark of joy.

- Steve Wilson

I’ve had a soft spot for BSA side-valve singles for 25 years. I acquired my first one, a 1955 600cc M21, in 1995, from dealer Andy Tiernan. It was extensively rebuilt by Sean Hawker, who formerly ran CMES, the classic electrical specialists. Sean and a friend had ridden their M21s on a 34,000 mile trip through southern Russia, into China, down through India and Malaya and all-round Australia, so he knew his side valves.

The following year, he and I took a 1500 mile roundtrip to a motor show on the Shetland Islands. Sean was riding his expedition bike. Neither of our BSAs missed a beat.

Peace of mind

When people ask me, or I ask myself, why the obsession and affection for 13 and 15bhp models, which where outdated even during their final decade of production, I recall something I’d written about the return leg of that Shetlands journey, riding from Aberdeen down the east coast of Britain on my own: “A breather pipe came loose, and the clutch got a bit snatchy, but at a steady 55 the engine never smoked or faltered. In the morning rush hour out of Newcastle, or crossing the mile-and-a-half Humber Bridge, or on the empty sweep of a Lincolnshire plateau, I came to realise what was missing – any of the usual anxiety about a breakdown, as the M21’s utter reliability brought peace of mind.”