| Forged from high-silicon aluminum alloy for maximum strength and dependability.. Innovative forging design and piston skirt provide maximum horsepower and torque.. Wiseco High-Performance piston kits are priced with piston, rings, pins and circlips (unless noted otherwise).. Oversize pistons require cylinder sleeving.. SPECIFICATIONS. Displacement: 183cc. Bore - Standard: 64.00mm. Bore - Actual: 64.00mm. Bore - Oversize: STD. Stroke | 57.00mm. ITEM CONTENTS. 2520CD - 64.00 mm Ring Set. CW16 - ROUND WIRE PIN LOCKS 16MM (PAIR). S256 - PistonPin 16mm x 2.047in. NonChromed TW |