Bagger Big Bore Kits

S&S Cycle - 128" Power Packages fits '17-'20 M8 Oil-Cooled Engines This Power Package increases your 114"/117" with a 4-1/2" stroke M8 to 128". It is available in a wrinkle black or black granite finish and your choice of cylinders with or without...

S&S Cycle - Wrinkle Black 124" Big Bore Kit W/O Highlighted Cylinder Fins fits '17-'21 107" M8 Engines This is a bolt-on kit that features the biggest bore possible with no machining of the crankcases necessary! It includes all of the required...

S&S Big Bore Kit for M8 Harley Softail & Touring '17-Up This S&S Big Bore Kit is for Milwaukee-Eight Harley Softail and Touring models 2017 and up, including Softail Heritage Classic and Breakout. Available as a whole kit or as a cylinder...

S&S Cycle - 110" Power Package fits '07-'17 Twin Cam Engines S&S Cycle has created the largest big-bore kits available today, without doing crankcase mods! This kit increases displacement to 110" ('07-'17) and the cylinders fit to the pistons...

S&S Cycle - 96" Big Bore Kit fits '84-'00 Evolution Big Twin Engines (3⅝" Bore, 4⅝" Stroke, 9.75:1 Compression Ratio W/ Stock Heads) The cylinders featured in this kit are built with premium aluminum castings with cast-in iron liners. This kit also...

S&S Cycle - Wrinkle Black 110" Bolt-In Sidewinder® 4" Big Bore Kit fits '07-'17 Twin Cam Engines This Big Bore Kit has a 10.5:1 compression ratio (W/ stock 85cc heads) that will transform your engine into a street-ready and reliable machine...

S&S Cycle - 100" Power Packages fits '99-'06 Twin Cam Engines (Exc. '06 Dynas) S&S Cycle has created the largest big-bore kits available today, without doing crankcase mods! This kit increases displacement to 100" ('99-'06) and the cylinders fit...

S&S Cycle - 136" Big Bore Cylinder Kit fits '17 & Up M8 Engines S&S Cycle's Big Bore Cylinder & Piston Kit delivers a mighty bore increase (4.320") that, in turn, delivers a huge power increase! It is compatible with stock crankcases,...

S&S Cycle - Black 4.375" Stroke 129" Big Bore Cylinder & Piston Kit fits '17 & Up M8 Engines S&S Cycle's Big Bore Cylinder & Piston Kit delivers a mighty bore increase (4.320") that, in turn, delivers a huge power increase! It is...

S&S Cycle - Black 4.5" Stroke 132" Big Bore Cylinder & Piston Kit fits '17 & Up M8 Engines S&S Cycle's Big Bore Cylinder & Piston Kit delivers a mighty bore increase (4.320") that, in turn, delivers a huge power increase! It is...

S&S Cycle - Black Granite 128" Big Bore Kit W/ Highlighted Cylinder Fins fits '17-'20 114" 117" M8 Engines This is a bolt-on kit that features the biggest cylinder bore possible with no machining of the crankcases necessary! It includes all of the...

S&S Cycle - Black Powdercoat 117" Big Bore Kit fits '07-'17 Twin Cam Engines (4.125" Bore, 4⅜" Stroke, 10.5:1 Comp. W/ Stock Heads) This Big Bore Kit produces outstanding outcomes with stock cylinder heads. It comes complete with cylinders, pistons,...

S&S Cycle - Black Powdercoat 95" Big Bore Kit fits '99-'06 Twin Cam Engines (3.875" Bore, 4" Stroke, 9.7:1 Comp. W/ Stock Heads) This Big Bore Kit produces outstanding outcomes with stock cylinder heads. It comes complete with cylinders, pistons,...

S&S Cycle - Black/Highlighted 4.375" Stroke 129" Big Bore Cylinder & Piston Kit fits '17 & Up M8 Engines  S&S Cycle's Big Bore Cylinder & Piston Kit delivers a mighty bore increase (4.320") that, in turn, delivers a huge power...

S&S Cycle - Black/Highlighted 4.5" Stroke 132" Big Bore Cylinder & Piston Kit fits '17 & Up M8 Engines  S&S Cycle's Big Bore Cylinder & Piston Kit delivers a mighty bore increase (4.320") that, in turn, delivers a huge power...

S&S Cycle - Silver 100" Bolt-In Sidewinder® 4" Big Bore Kit fits '99-'06 Twin Cam Engines This Big Bore Kit has a 10.5:1 compression ratio (W/ stock 85cc heads) that will transform your engine into a street-ready and reliable machine which will...

S&S Cycle - Silver 110" Bolt-In Sidewinder® 4" Big Bore Kit fits '07-'17 Twin Cam Engines This Big Bore Kit has a 10.5:1 compression ratio (W/ stock 85cc heads) that will transform your engine into a street-ready and reliable machine which will...

S&S Cycle - Silver Powdercoat 95" Big Bore Kit fits '99-'06 Twin Cam Engines (3.875" Bore, 4" Stroke, 9.7:1 Comp. W/ Stock Heads) This Big Bore Kit produces outstanding outcomes with stock cylinder heads. It comes complete with cylinders, pistons,...

S&S Cycle - Stone Gray Powdercoat 117" Big Bore Kit fits '07-'17 Twin Cam Engines (4.125" Bore, 4⅜" Stroke, 10.5:1 Comp. W/ Stock Heads) This Big Bore Kit produces outstanding outcomes with stock cylinder heads. It comes complete with cylinders,...

S&S Cycle - Stone Gray Powdercoat 124" Big Bore Kit fits '07-'17 Twin Cam Engines (4.125" Bore, 4⅝" Stroke, 11.4:1 Comp. W/ Stock Heads) This Big Bore Kit comes complete with cylinders, pistons, rings and gaskets (head, base and exhaust)...

S&S Cycle - Wrinke Black 128" Big Bore Kit W/ Highlighted Cylinder Fins fits '17-'20 114" 117" M8 Engines This is a bolt-on kit that features the biggest cylinder bore possible with no machining of the crankcases necessary! It includes all of the...

S&S Cycle - Wrinke Black 128" Big Bore Kit W/O Highlighted Cylinder Fins fits '17-'20 114" 117" M8 Engines This is a bolt-on kit that features the biggest cylinder bore possible with no machining of the crankcases necessary! It includes all of the...

S&S Cycle - Wrinkle Black 100" Bolt-In Sidewinder® 4" Big Bore Kit fits '99-'06 Twin Cam Engines This Big Bore Kit has a 10.5:1 compression ratio (W/ stock 85cc heads) that will transform your engine into a street-ready and reliable machine...

S&S Cycle - Wrinkle Black 124" Big Bore Kit W/ Highlighted Cylinder Fins fits '17-'21 107" M8 Engines This is a bolt-on kit that features the biggest bore possible with no machining of the crankcases necessary! It includes all of the required...