KB931C005 Performance, 1200cc B.T. forged piston kit. +.005"

If you are refreshing a classic Big Twin, this KB Performance forged piston kit is a solid upgrade for 1941 to 1978 1200cc Knucklehead, Panhead, and Shovelhead models. These +.005 inch oversize pistons provide a reliable 8.5:1 compression ratio with a 112cc head, making them an excellent choice for vintage builds. Forged from 4032 aluminum alloy with 11% silicon, they offer high strength and excellent resistance to cracking under pre-ignition. The kit is sold as a set, complete with offset wrist pins, retaining rings, and a full ring set. Due to the expansion characteristics of the forged alloy, we recommend a slightly wider piston-to-wall clearance of about .001 inch compared to cast alternatives. Always check the orientation marks for the front and rear sections before fitting.