BSA B44 Piston +20. 79.5mm
BOA45. 41-0797+20+20 = 79.5 mm GPM, cpl.
compr. ratio 9.4:1
Made by GPM
Middle gudgeon pin to lowest point of piston: 29 mm
Middle gudgeon pin to highest point of piston: 41,5 mm
Gudgeon pin diam. 19 mm
can be used f. Norton
Piston Clearance 0.12mm or 45thou