Inspired by our Pro Stock Drag Race engines, these updated big bore kit utilizes a Ductile Cast Iron liner wrapped in cast aluminum for optimum thermal conductivity and performance. Bolt-in kits do not require machining, rebalancing or engine removal, and include just about everything you’ll need to complete the installation. The biggest cylinder bore that can be installed in a stock crankcase without machining!
Features & Benefits
- Low friction Ductile Cast Iron liner
- 10.5:1 Compression -Bolts in. No machining, balancing, or splitting the crankcases
- 96 and 103" engines are boosted to 110"
- Complete kits include cylinders, pistons, gaskets, and instructions
- Wrinkle black cylinders – matches stock finish
- Although not mandatory, we recommend adding an oil cooler to bikes ridden in warmer climates
| Stroke |
Bore |
Cylinder Length |
Piston Type |
Dome Volume |
83cc CNC Heads |
85cc Stock Heads |
89cc S&S Heads |
| 4.375 |
4.00" |
4.937" |
Forged |
.75 pop up |
10.7:1 |
10.5:1 |
10.2:1 |
*Not compatible with S&S 79cc Super Stock® heads and 2014-'16 Twin-Cooled™ touring models. S&S does not recommend compression ratios higher than 10:1 for Tri Glide® or other three wheel models (including conversions) due to extra loads caused by the lugging nature of these bikes. Detonation and subsequent engine damage may result.
