S&S Cycle 99-06 BT 3.927in +.010in Bore 97in Big Bore Forged Pistons

We use UPS, FedEx, DHL, and USPS for deliveries. We are not responsible for any shipping problems and shall not be held liable for any "reasonable" delay beyond our advertised delivery time-frames. Shipment by Ground Courier can take up to 15 business days for delivery. Express Courier can take up to 3 business days for delivery. Shipping time frames are once the order has been processed. Due to high demand, order processing can take 5 to 7 business days.

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" +.010" bore.