S&S CYCLE Bolt-In Sidewinder® 4" Big Bore Kits — 110", 10.5:1 – 08, 11-17 Dyna, 09-16 Trike, 10-11 Touring, 07-17 Softail

Bolt-in installation requires no machining, balancing, or splitting the crankcases; installation can be performed with the engine still in the frame. 🔧

Cast ductile iron sleeve in cast aluminum provides superior heat transfer and long service life.

Boosts 88" engines to 100", and 96" and 103" engines to 110" for increased displacement and stronger midrange power.

10.5:1 compression with stock 85cc heads offers a very streetable, dependable setup that also responds well to performance cams.

Complete kit includes cylinders, forged pistons, rings, piston pins, clips and gaskets for a full cylinder-and-piston replacement.

Not for use with S&S 79cc heads.

Not recommended for trike models or for Twin-Cooled models.