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

VT No: 11-2256
Keith Black piston set is .040 oversize and is for a 3.498 " 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" 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.
Fits:
FL 1978-1984
FX 1978-1984
FLT 1979-1983
FXR 1982-1983
UOM: 2 - SET
Country of Origin: Imported

Size: .040
Manufacturer: Keith Black
2018 Catalog pages: 531

2017 Catalog Page: 535

V-Twin Manufacturing Part Number: 11-2256
Manufacturer: Keith Black
Manufacturer Part Number: KB297 .040

Harley-Davidson & Indian OEM Cross Reference Part Numbers:            

Replacement Items:
11-1367 - 80" Shovelhead Piston Ring Set .040

Detailed Instructions: CLICK HERE!