BSA A65 Star

The BSA A65 Star was the 650 cc unit construction parallel twin that Birmingham Small Arms built from 1962 to 1972 as the successor to the older pre-unit A7 and A10 twins. Engine and gearbox shared one casting, the pushrod passages were cast into the cylinder block, and the design aimed to give a cleaner look and fewer places for oil to leak. It was developed under managing director Bob Fearon with chief development engineer Bert Perrigo, with the American market firmly in mind. Twelve volt electrics arrived in 1966 and an oil in frame chassis in 1970. Vibration and dated styling counted against it, and it was dropped as BSA ran into financial trouble.