S&S Cycle SS320-0598 4-1/2 Stroke Flywheel Assembly for 114ci to 117ci Milwaukee-Eight Touring 17-Up/Softail 18-UpThe flywheels are the heart of any performance engine and S&S Cycle has been perfecting the art for over six decades. Stronger, more durable, and trued to a spec others can only dream of, the new cranks for the Milwaukee Eight platform are the best of the best to build your high performance engine around. FEATURES & BENEFITS 4 1 2" Stroke (114 or 128ci) Balance Gear installed Heat Treated 4140 Material is harder & more than twice as strong as stock