JE Pistons 370251 Flat 4.125" 120ci Big Bore Piston Set Harley M8 17-Up

• Forged from 2618-T6 aluminum for better aligned grain flow and higher tensile strength
• Skirt coating aids in optimal break-in for performance longevity
• High 11.0:1 compression ratio for improved performance
• Accumulator groove provides additional volume for combustion pressure

Specs

Bore Diameter 104.78
Piston Head Type Flat
Piston Volume -1.3
Pin Part Number 927-2500-15-51C
Piston Pin Inside Diameter 0.627
Piston Pin Length 63.50
Piston Pin Outside Diameter 0.927
Retainer Lock Part Number 927-073-MW
Ringset Included Yes
Ringset Number JG31F1-4125-2
Top Compression Ring Thickness 0.0472
Second Compression Ring Thickness 0.0591
Oil Ring Thickness 0.1181
Piston Material 2618
Forging Type Round
Piston Avg Weight 399
Compression Ratio 11.00:1