HardDrive’s Big Bore Cylinder Kits are an easy way to upgrade your V-Twin. All components are cast from premium materials, and the cylinders come powder-coated with machined finishes and match perfectly to Harley-Davidson motors.
All kits feature Cometic head and base gaskets and provide easily installed bolt-on horsepower. The Milwaukee-Eight 128ci kit ($1,298.95) brings stock M-8 114ci and 117ci motors to 128ci, with a 4.5-inch stroke and 11:1 compression. The M-8 124ci kit ($1,298.95) brings stock 107ci motors up to 124ci, with a 4.375-inch stroke and 11:1 compression. And the Twin Cam 110ci kit ($1,244.95) brings 2007-2016 stock 96ci and 103ci motors to 110ci, with a 4.375-inch stroke and 10.5:1 compression.
For more information, including charts with cam and component suggestions, check out the Hard Drive online catalog.