8:1 Compression BSA B40 Piston +60 = 80.5mm Pin diameter: 19.00 mm Middle Gudgeon Pin to top of piston: 41.25 mm Length Gudgeon Pin: 66 mm Piston Clearence 0.12mm or 45thouwith Piston Rings, Circlips and Gudgeon Pin
BSA B33 Piston Ring Set / Piston Rings +040
+040=86mm
500cc
Oil Ring: 4mm thick, 3.5mm deep
Upper + Middle Ring: 2.35mm thick
Made in Taiwan - have proofed to be succesfull