ZIPPERS PERFORMANCE BIG BORE KITS HARLEY TWIN CAMS 07-17 HARLEY FXR SEATS to ensure optimum brake pat-to-rotor

to ensure optimum brake pat-to-rotor contact

220° full-coverage muffler heat shields house the Straightshots HS slip-ons and make them blue-proof for long-lasting style

Updated front and rear compounds offer enhanced wear resistance and wet-weather performance

Straight can mufflers with a specially designed baffle that is acoustically tuned to deliver a unique exhaust sound while providing maximum performance

Replacement retaining rings can be purchased separately

ZIPPERS PERFORMANCE BIG BORE KITS HARLEY TWIN CAMS 07-17 HARLEY FXR SEATS to ensure optimum brake pat-to-rotorZIPPERS PERFORMANCE BIG BORE KITS HARLEY TWIN CAMS 07 17 SELECT IN OPTIONS KITS FOR 2007 UP TWIN CAM ENGINES Factory 2007 up Twin Cam engines are equipped with 4 3 8 stroke crankshafts. The factory cylinder bore size of 3 3 4 yields the 96 displacement, which was gradually increased to 3 7 8 starting in 2010 for 103 displacement. We can turn your 96 engine into either a 103 or a 107, and your 103 into a 107 simply by resizing the factory cylinders.