Skip to content
FREE SHIPPING ON ALL ORDERS OVER $150 - JUST ADD TO CART (exclusions may apply)
FREE SHIPPING ON ALL ORDERS OVER $150 - JUST ADD TO CART (exclusions may apply)

S&S 136" Big bore kit M8

by S&S
Sold out
Original price $1,599.95 - Original price $1,599.95
Original price
$1,599.95
$1,599.95 - $1,599.95
Current price $1,599.95
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 4.320” cylinders to net a tire melting 136 cubic inches when paired with their 4.625” stroker crank. We build our big bore kits and cranks to much tighter tolerances and with higher quality materials than the factory parts. This new piston/cylinder kit will be a solid platform for massive power.
  • Huge displacement increase (4.320" Bore) means a huge power increase
  • Works with stock crankcases
  • Original engine serial numbers are retained
  • Powder coat finish matches factory finish
  • MLS (multi-layered steel) head gaskets
  • Retains stock engine height
  • Includes 136" Cam Cover Badge
  • Requires 4 5/8" Stroker Crank

Fitment :

  • '17+ Touring
  • '18+ Softail models

Notes:

  • For a build of this level, you should definitely consider the new MK engine cases!
  • Not recommended for Trike models due to the lugging nature

DISCLAIMER: NOT LEGAL FOR SALE OR USE IN CALIFORNIA ON ANY POLLUTION-CONTROLLED MOTOR VEHICLES.

IF FOR RACE OR OFF-HIGHWAY USE OUR CA EXHAUST WAIVER WILL NEED TO BE SIGNED AND RETURNED PRIOR TO SHIPPING. 

CALIFORNIA CARB WAIVER AVAILABLE HERE:

https://cdn.shopify.com/s/files/1/0157/0363/8064/files/CA_CARB_Waiver.pdf?573