BSA

C15 Star

249cc ohv single || 320lb || 70mpg || 70mph || 1959-67

Redesigned basic 250, with neat but restrained streamlined styling and unit construction. Some suffered bottom end and ignition troubles; most just whined on and on, as the basic design was rugged enough. Massive numbers were sold, which meant that even in the ‘classic’ age they were so plentiful that they are often neglected.

Buy with care, 1970s learner riders did terrible things to them. Sports version was the SS80, which was quicker and less reliable. C15T and C15S will cost more. Before paying a lot more for a T or an S, make sure they’re genuine.

Prices: low £1500 || high £3250

B33

499cc ohv single || 420lb || 70mpg || 80mph || 1947-59

Enlarged B31, with more torque so longer legs. Possibly the classic 1950s workhorse, this one will run and run. Plunger suspension from 1949, then the admirable BSA swinging arm frame arrived in 1955. Alternator/coil ignition in 1958. Similar values for the M33, which is essentially an ohv (B33) engine in a side valve (M21) bicycle. All extremely straightforward to maintain and easy to live with: a solid bet for any beginner.

Prices: low £2500 || high £4000