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S&S 132" Big Bore Kit

Item: 403992

$1349.96 – $1484.96

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Select Your Vehicle - Fitment Guaranteed

S&S 132" Big Bore Kit


  • Huge bore increase to 4.320" means huge power gains on your Milwaukee Eight 114 inch engine
  • Retains stock engine height
  • Powder coat finish match factory finish, giving the bike a sleeper advantage
  • Works with stock crankcases
  • MLS (multi-layered steel) head gaskets
  • Original engine serial numbers are retained
  • Includes cam cover badge
  • Made in the USA
Specification Details
Bore 4.32 in.
Color Varies (make selection above)
Compression Ratio 11:1
Country of Origin USA
Displacement 132CI
Engine Type Milwaukee Eight 114
Finish Powder Coated
Stroke 4.5 in.
Warranty Varies (make selection above)

Vehicle Fitment


Fitment is guaranteed or your money back plus free return shipping.
Don’t waste time installing a product that doesn't fit. We worked hard ensuring that this product is an exact fit on the vehicles listed below.

Harley Davidson
  • FLFB Softail Fat Boy 2025
  • FLFBS Softail Fat Boy 114 2018-2024
  • FLHC Softail Heritage Classic 2025
  • FLHCS Softail Heritage Classic 114 2018-2024
  • FLHRXS Road King Special 2019-2023
  • FLHTCU Electra Glide Ultra Classic 2019
  • FLHTCUTG Tri Glide Ultra Classic 2019-2025
  • FLHTK Electra Glide Ultra Limited 2019-2023
  • FLHXS Street Glide Special 2019-2023
  • FLRT Freewheeler 2022-2025
  • FLTRK Road Glide Limited 2020-2023
  • FLTRT Road Glide 3 2023-2025
  • FLTRU Road Glide Ultra 2019
  • FLTRXS Road Glide Special 2019-2023
  • FXBB Softail Street Bob 2025
  • FXBBS Softail Street Bob 114 2021-2024
  • FXBR Softail Breakout 2018-2019
  • FXBRS Softail Breakout 114 2018-2020
  • FXDR Softail 114 2019-2020
  • FXFBS Softail Fat Bob 114 2018-2023
  • FXLRS Softail Low Rider S 2020-2021

Customer Reviews


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Questions & Answers


do i need to change my cams or anything else

These components are designed to bolt straight in place of the original cylinders and pistons for any machine you select from our fit guide. There's no need for cams or any other parts, Still, you WILL want to change fuel delivery, that's for sure, a tune is required if you expect your bike to run correctly. Depending on your situation, we recommend the Vance & Hines FP4 if you want to avoid a trip to the dyno. Or, if you have a technician you trust, we recommend a Power Vision 4 tuner to get the best possible engine performance. The latter, while more time consuming and costly, is the best way to get a custom map built that'll get you all the power possible from this big bore kit.

By Tom

what is the compression ratio with these pistons?

Assuming you're working with 0.030" head gaskets, you'd obtain a compression ratio of 11:1 with this cylinder kit.

By Tom

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