80 FLH-FX Piston Set.040 Oversize - Keith Black KB297.040

Keith Black #: KB297.040

Keith Black piston set is.040 oversize and is for a 3.498 inch bore. Piston set has a compression of 8.3:1 and includes rings.

The Keith Black 390 hypereutectic alloy is cast in a permanent steel mold which makes it possible to build a light weight piston that makes more power and uses less fuel and lasts longer. Pistons are.040 oversize for a 3.498 inch bore and has a 9.5:1 compression ratio. The low heat transfer of the alloy keeps the skirts cool so piston expansion is minimal. The combination of a low heat transfer piston alloy and high compression ring placement increases power and economy. The high ring placement alone reduces detonation and increases the top ring temperature. **Note: Run engine at moderate speeds for at least 500 miles avoiding excessive running in lower gears in order to properly break-in new pistons and rings.

Fitment:

Installation instructions (PDF)