***LIMITED ITEM PLS ALLOW 4 BUSINESS DAYS HANDLING TO SHIP*** Piston set 3-3/16 inch bore standard size has a compression ratio of 8.4:1. Set includes Hasting 3 piece rings 2 wrist pins and 4 circlips. **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 HARLEY: 1972-1985 XL,