+.010in. Flat Top Pistons with 8.6:1 Compression Ratio. Fits Big Twin 1984-1999 with Evo Engine. - Keith Black Pistons Brake Hardware * Does not fit Touring

* Does not fit Touring Models with Lower Fairings

* Inner Diameter = 1

* Universal Tapered style

Bakelite cap

* Original Style Polished Stainless Round Spokes

+.010in. Flat Top Pistons with 8.6:1 Compression Ratio. Fits Big Twin 1984-1999 with Evo Engine. - Keith Black Pistons Brake Hardware * Does not fit TouringFeatures & Benefits: * Bore = 3. 508" * Stroke = 4. 250" * Hypereutectic Alloy is a cast 16% silicon content material. * Perfect for air cooled engines. * Low thermal expansion rate = tighter piston to cylinder clearance. * Complete kit includes: two pistons, rings, wrist pins and clips. * Replaces OEM # 21942 83 Tech Tips: * 8. 6: 1 Compression Ratio with 80cc Head Chamber Volume. * Follow Ring End Gap & Piston to Cylinder Clearances as per the