This is the later B1 model with the larger spark plug.
Valve Guide Fitting and Removal Tool for Classic Vintage BSA Models
BSA C15 250cc STAR MOTORCYCLE METAL SIGN.(A3) SIZE.VINTAGE BSA MOTORCYCLES.
BSA Sloper Side Valve Gasket S
Vintage Washers Flat Valve Discs And Springs For Douglas And Other Vintage
Vintage BSA OHV Engine pre war B34 B2 250cc 1930s
Champion Spark Plug L82C Vintage BSA Replaces L7
