910-0684A 114" to 128" big bore conversion cylinder & piston kit
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Specifications
- Brand
- S&S
- Part Number
- 910-0684A
- OEM Reference
- —
- Pack Quantity
- Sold as kit
- Category
- Cylinder And Piston Kits
- VAT Rate
- 20%
About This Product
This S&S Cycle 128 inch big bore conversion kit is the perfect performance upgrade for 2017 to 2025 Milwaukee-Eight 114 inch engines. This version features black wrinkle cylinders with highlighted fins to match the premium aesthetic of your motor. The kit provides a massive displacement increase to 2092cc using forged 4.250 inch bore pistons and the stock 4.5 inch stroke. It is designed for easy installation with no case boring or flywheel rebalancing required. You will achieve an 11:1 compression ratio using your stock cylinder heads. The kit comes as a complete package including all necessary gaskets and hardware. We suggest pairing this with S&S high-strength head bolts to ensure long-term reliability under the increased power loads.
Manufacturer part number: 910-0684A.
Fitment
42 models17-25 114" M8
Police 8 models
| Brand | Year | Model |
|---|---|---|
| Harley-Davidson | 2019–2020 | Electra Glide Standard Police FLHTP |
| Harley-Davidson | 2025 | Police Electra Glide FLHTP |
| Harley-Davidson | 2021–2024 | Police Electra Glide FLHTP |
| Harley-Davidson | 2025 | Police Road Glide FLTRXP |
| Harley-Davidson | 2024 | Police Road Glide FLTRXP |
| Harley-Davidson | 2025 | Police Road King FLHP |
| Harley-Davidson | 2021–2024 | Police Road King FLHP |
| Harley-Davidson | 2019–2020 | Road King Police FLHP |
Softail 13 models
| Brand | Year | Model |
|---|---|---|
| Harley-Davidson | 2018 | Breakout 114 Anniversary FXBRS |
| Harley-Davidson | 2018–2022 | Breakout 114 FXBRS |
| Harley-Davidson | 2018 | Fat Boy 114 Anniversary FLFBS |
| Harley-Davidson | 2020 | Fat Boy 114 Anniversary FLFBSANV |
| Harley-Davidson | 2018–2024 | Fat Boy 114 FLFBS |
| Harley-Davidson | 2023 | Fat Boy Anniversary FLFBSANV |
| Harley-Davidson | 2019 | FXDR 114 FXDRS |
| Harley-Davidson | 2018 | Heritage Classic 114 Anniversary FLHCS |
| Harley-Davidson | 2018–2024 | Heritage Classic 114 FLHCS |
| Harley-Davidson | 2023 | Heritage Classic Anniversary FLHCSANV |
| Harley-Davidson | 2024 | Hydra-Glide Revival FLI |
| Harley-Davidson | 2020–2021 | Low Rider S FXLRS |
| Harley-Davidson | 2021–2024 | Street Bob 114 FXBBS |
Touring 14 models
| Brand | Year | Model |
|---|---|---|
| Harley-Davidson | 2023 | Electra Glide Highway King FLHFB |
| Harley-Davidson | 2021 | Revival FLH |
| Harley-Davidson | 2023 | Road Glide Anniversary FLTRXSANV |
| Harley-Davidson | 2020–2024 | Road Glide Limited FLTRK |
| Harley-Davidson | 2019–2023 | Road Glide Special FLTRXS |
| Harley-Davidson | 2019 | Road Glide Ultra FLTRU |
| Harley-Davidson | 2025 | Road King Special FLHRXS |
| Harley-Davidson | 2019–2024 | Road King Special FLHRXS |
| Harley-Davidson | 2023 | Street Glide Anniversary FLHXSANV |
| Harley-Davidson | 2019–2023 | Street Glide Special FLHXS |
| Harley-Davidson | 2023 | Ultra Limited Anniversary FLHTKANV |
| Harley-Davidson | 2019–2024 | Ultra Limited FLHTK |
| Harley-Davidson | 2019 | Ultra Limited Low FLHTKL |
| Harley-Davidson | 2019–2023 | Ultra Limited Shrine Edition FLHTK |
Trike 7 models
| Brand | Year | Model |
|---|---|---|
| Harley-Davidson | 2025 | Freewheeler FLRT |
| Harley-Davidson | 2019–2024 | Freewheeler FLRT |
| Harley-Davidson | 2025 | Road Glide 3 FLTRT |
| Harley-Davidson | 2023–2024 | Road Glide 3 FLTRT |
| Harley-Davidson | 2025 | Tri Glide ULTRA FLHTCUTG |
| Harley-Davidson | 2023 | Tri Glide Ultra Anniversary FLHTCUTGANV |
| Harley-Davidson | 2019–2024 | Tri Glide Ultra FLHTCUTG |
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