
compression ratio: 9.75:1, +0.060", 3-ring piston. Compression rings = 0.0591", oil ring = 0.1181"
Mini All A Series engines with 1275 cc and A+ Series engines with 12H engine prefix
Sprite / Midget All 1275 cc engines
Mini All A Series engines with 1275 cc and A+ Series engines with 12H engine prefix
Sprite / Midget All 1275 cc engines