THIS 1971 THUNDERBOLT HAS NOT strayed far from its Cardiff home since 1971. We spotted it at the South Wales Sunbeam Club Classic Show and thought you may like a closer look.
Jim Harding has owned this 650cc BSA Thunderbolt since 1993, and he’s the third owner. And it’s his second bike. The first was an MZ 150 he used to get to work on. Jim didn’t know anything about British motorcycles when he bought from a local owner at a time when oil-in-frame BSAs were about as unloved as it was possible for a motorcycle to be. And it was the A65 at its most basic. Not so much as a rev counter was fitted to this bargain basement model. When Jim got the Thunderbolt, it was a frame, an engine, and lot of worn-out bits in boxes that had been dismantled in 1988 for a rebuild that never happened. After five years, the previous owner’s unexpected new family required him to sell it to Jim, who snapped it up.
An A65 is a challenging first project, but fortunately for Jim, he was pointed in the direction of Cardiff-based BSA twin guru and SRM founder Steve McFarlane. The other advantage is that Jim was an engineer, working at the time for British Airways at its engine plant in nearby Caerphilly. You don’t get to work on Boeing 747 engines without knowing what you are doing and working out how things mechanical can go together properly.
Jim stripped the engine with the help of Steve, who sorted out the primary chain, cleaned out the sludge trap and gave it a crank rebalance. With few miles on the clock, the engine went back together with stock pistons. The frame was painted with two-pack black enamel, after a dipping to inspect that all was sound.
Jim, being something of a perfectionist, got everything that could be polished, polished by Caerphilly Polishers, starting with the brake hubs,and.
