Rocket Performance Garage 124" Big Bore Cylinder Kit - Milwaukee-Eight 2017-2024
About Rocket Performance Garage Llc
Rocket Performance Garage builds V-twin performance and custom parts, working in the modern bagger and Softail space.
The Rocket Performance Garage 124 cubic inch big bore cylinder kit is engineered for 2017-2024 Harley Milwaukee-Eight engines, increasing displacement for significant power gains. This kit features USA-cast premium cylinders paired with CP forged pistons, designed for measurable performance improvements without requiring an extensive engine teardown.
Why riders pick this
- Increases Milwaukee-Eight displacement to 124 cubic inches
- USA-cast premium cylinders for quality and durability
- CP forged pistons included for high-performance reliability
- 10.5:1 compression ratio for enhanced power output
- Machined fins maintain a stock OEM aesthetic
When you're ready to take your Milwaukee-Eight to the next level, the Rocket Performance Garage 124" big bore cylinder kit provides a robust foundation for increased power. This kit is specifically designed for 2017-2024 M8 engines, boosting their displacement to 124 cubic inches. Featuring USA-cast cylinders with a textured black powdercoat and precision-matched CP forged pistons, this kit ensures both performance and a factory-like appearance.
Boost Your M8's Displacement
- Increases Milwaukee-Eight displacement to 124 cubic inches
- USA-cast premium cylinders for quality and durability
- CP forged pistons included for high-performance reliability
- 10.5:1 compression ratio for enhanced power output
- Machined fins maintain a stock OEM aesthetic
The Next Step in Milwaukee-Eight Performance
A big bore kit is a critical upgrade for any rider looking to extract maximum power from their Milwaukee-Eight. The Rocket Performance Garage 124" kit is an excellent choice for riders seeking a substantial power bump with reliable components. While it offers significant gains, professional installation is always recommended to ensure proper clearances and assembly. Combine this big bore kit with a performance cam, a high-flow air cleaner, and a custom dyno tune to truly transform your Harley Touring or Softail into a torque monster.
Specifications
- Brand: Rocket Performance Garage
- Manufacturer Part #: 8-8101
- Displacement: 124 cubic inches
- Compression Ratio: 10.5:1
- Piston Brand: CP (forged)
- Length: 9 in
- Width: 8 in
- Height: 20 in
- Weight: 25 lbs
- Country of Origin: USA
Common questions
What Harley engines is this 124" big bore kit compatible with?
This Rocket Performance Garage kit is specifically engineered for 2017-2024 Harley-Davidson Milwaukee-Eight (M8) engines. It is not compatible with Twin Cam or earlier platforms.
Will I need a fuel tuner and dyno tune after installing this kit?
Yes, any significant engine modification, such as a big bore kit, requires a performance fuel tuner and a professional dyno tune to optimize air/fuel ratios, maximize power, and ensure engine longevity.
Is professional installation necessary for this big bore kit?
Yes, installing a big bore cylinder kit involves critical engine disassembly and precise measurements. We highly recommend having a qualified Harley-Davidson technician or performance shop perform the installation.
Ordering from Vtwinbikers
- Brand new, sourced through authorized US distribution — never used, never grey-market.
- Not sure it fits? Use Shop by Bike to filter by your year and model, or email us and we will confirm before you order.
- Harley-Davidson and Indian Motorcycle is all we do, so you are talking to people who ride what you ride.
| BRAND | Rocket Performance Garage Llc |
| TYPE | Engine |
| SKU | 276-02061 |
| WEIGHT | 25.0 lb |
