S&S Cycle 2007+ BT 4.250in Bore 4.840in – Wrinkle Black w/o Highlight

S&S has been building big bore kits since the 60s and has it down to an absolute science. Our latest efforts are aimed at the Milwaukee Eight® platform (2017 and newer big twins) and open up a whole new level of performance for these engines. Combining a new design forged piston with their 4.25″ cylinders to net a tire melting 131 cubic inches when paired with their 4.625″ stroker crank. We build our big bore kits and cranks to much tighter tolerarances and with higher quality materials than the factory parts. This new piston/cylinder kit will be a solid platform for massive power.

• Must be used with our stroker flywheels to achieve 131″ displacement (part #s 320-0605, 320-0620)
• Powder coat finish match factory finish, giving the bike a “sleeper” advantage
• Huge displacement increase means huge power increase
• .030″ MLS (multi-layered steel) head gaskets
• Original engine serial numbers are retained
• Includes 131″ Cam Cover Badge
• Works with stock crankcases
• Retains stock engine height

Fitment:
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Harley Davidson FLHRC Road King Classic Base 2017 to 2019
Harley Davidson FLHRXS Road King Special Base 2017 to 2020
Harley Davidson FLHT Electra Glide Standard Base 2019 to 2020
Harley Davidson FLHTCU Electra Glide Ultra Classic Base 2017 to 2019
Harley Davidson FLHTCUTGSE CVO Tri Glide Base 2020
Harley Davidson FLHTK Ultra Limited Base 2017 to 2020
Harley Davidson FLHTKL Ultra Limited Low Base 2017 to 2020
Harley Davidson FLHTKSE CVO Limited Base 2017 to 2020
Harley Davidson FLHX Street Glide Base 2017 to 2020
Harley Davidson FLHXS Street Glide Special Base 2017 to 2020
Harley Davidson FLHXSE CVO Street Glide Base 2017 to 2020
Harley Davidson FLRT Freewheeler Base 2017 to 2020
Harley Davidson FLTRK Road Glide Limited Base 2020
Harley Davidson FLTRU Road Glide Ultra Base 2017 to 2020
Harley Davidson FLTRX Road Glide Base 2017 to 2020
Harley Davidson FLTRXS Road Glide Special Base 2017 to 2020
Harley Davidson FXBRS Breakout 114 Base 2018 to 2020
Harley Davidson FXDRS FXDR 114 Base 2019 to 2020
Harley Davidson FXFBS Fat Bob 114 Base 2018 to 2020