Replacement flathead 45 flywheels fit 1937–'73, 45" flathead engines except KH models. S&S replacement flywheels for KR/WR incorporate a modern crankpin taper, and must be used with a special tapered crankpin (34-2513, included). Compatible stock rods for KR or ironhead Harley-Davidson® Sportster® models, in conjunction with the special crankpin. A complete set of S&S connecting rods specifically designed for these flywheels are available. The S&S rod set includes the special crankpin, bearings, cages, and S&S heavy duty connecting rods.
Not available balanced or assembled.
Features and Benefits
- 3 13/16" stroke
- Fits 45" flathead, 45" KR and WR engines
- Complete S&S connecting rod set – includes special crankpin, rods, bearings and cages
- Compatible with stock 45" KR rods or rods for 1957–'84 Sportster models, when used with the special crankpin
Harley-Davidson® part number 23925-37.
Note: All reference to H-D® part numbers is for identification purposes only. We in no way are implying that any of S&S Cycle's products are original equipment parts or that they are equivalent to the corresponding H-D® part number shown.