Std Dome Top Pistons with 9.6:1 Compression Ratio. Fits Big Twin 1984-1999 with Evo Engine. - Keith Black Pistons Foot Controls & Extensions * CNC Machined Aluminium

* CNC Machined Aluminium

* Direct replacement on almost all models with under handlebar control mounted signals

* Width 31

* Made of Lucite for best quality and durability

* Spring compression tool required for installation KM-K66030

Std Dome Top Pistons with 9.6:1 Compression Ratio. Fits Big Twin 1984-1999 with Evo Engine. - Keith Black Pistons Foot Controls & Extensions * CNC Machined AluminiumFeatures & Benefits: * Bore = 3. 498 * 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. Tech Tips: * 9. 6: 1 Compression Ratio with 80cc Head Chamber Volume. * Follow Ring End Gap & Piston to Cylinder Clearances as per the supplied Manufacturers