These big bore pistons work with the stock 4" stroke flywheels to convert any 1999-'06 HD® big twin engine from 88" to 97" displacement with 9.7:1 compression with stock heads. Stock cylinders may be bored to accomodate larger pistons, but we recommend S&S 3.927" bore cylinders which feature high strength alloyed cast iron liners. Pistons are compatible with stock rods with tapered wristpin ends. S&S® 3.927" bore pistons are machined to such close tolerances that it is not necessary to measure the piston. Just bore cylinders to nominal diameter +/- 0.0005" for correct clearance. Additionally, the low friction coating on the piston skirt makes taking measurements very difficult. 3.927" standard bore.
Key Features
Brand Manufactured by S&S Cycle
Category Engine Components
Type Piston Sets - Powersports
Specifications
Length 8.63 in
Width 4.75 in
Height 4.75 in
Weight 2.85 lbs
Rider Benefits
These big bore pistons work with the stock 4" stroke flywheels to convert any 1999-'06 HD® big twin engine from 88" to 97" displacement with 9.7:1 compression with stock heads. Stock cylinders may be bored to accomodate larger pistons, but we recommend S&S 3.927" bore cylinders which feature high strength alloyed cast iron liners. Pistons are compatible with stock rods with tapered wristpin ends. S&S® 3.927" bore pistons are machined to such close tolerances that it is not necessary to measure the piston. Just bore cylinders to nominal diameter +/- 0.0005" for correct clearance. Additionally, the low friction coating on the piston skirt makes taking measurements very difficult. 3.927" standard bore.
Please review manufacturer details to ensure proper fitment before ordering.