788977 Flywhl Assy 4 5 8 Str Full Width Wp Me1

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£1485.61

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Specifications

Brand
S&S Cycle
Part Number
788977
OEM Reference
—
Application
4 5/8" Stroker flywheels for custom-build High Performance motorsNote: These do not have the same connecting rod length as in 121CI VVT engines 2023 to present, Complete flywheel assembly with full width piston wrist pin ends and balancer gear installed
Pack Quantity
Each
Category
Crankshafts & Parts
VAT Rate
20%

About This Product

S&S Cycle high-compression 132CI and 136CI big bore kits for Milwaukee Eight engines. The cylinders keep the stock deck height and use the original serial number locations. No crankcase machining is required. The finish matches factory powder coat. Each kit includes gaskets. Fits Softail, Touring, and Trike models. Degree the cams and check piston-to-valve clearance. Do not assume the gasket kit has the base gaskets you need; check the contents before you open the cases.

Manufacturer's description

The crankshaft is the heart of any performance engine and S&S has been perfecting the art for over six decades. Stronger, more durable, and trued to a spec others can only dream of, these crankshaft assemblies for the Milwaukee Eight are the best of the best to build your high performance engine around. Made out of heat treaded 4140 material, harder and more than twice as strong as stock. The stronger assembly eliminates the need to weld the crankpin. The High Strength connecting rods are designed with Finite Element Analysis to eliminate weak spots and handle more power. Consistent balance and precision machining makes them capable of higher RPM and perfect for gear drive cams. Crankshafts that have connecting rods with tapered piston wrist pin ends can be used with stock or S&S pistons. The full-width version can only be used with S&S pistons and S&S Big Bore cylinder kits. Crankshafts with 4 5/8" stroke can only be used with pistons that are designed for this stroke.

4 5/8" stroke gives:

- 113CI from a 107CI engine with stock 3 15/16" bore
- 117CI from a 114CI engine with stock 4 1/64" bore
- 121CI from a 117CI engine with stock 4 5/64" bore
- 131CI with an S&S 4 1/4" Big Bore kit
- 136CI with an S&S 4.320" Big Bore kit

Fitment

42 models

Softail | Touring | Trike

Softail
16 models
Brand Year Model
Harley-Davidson 2023–2026 Breakout® FXBR
Harley-Davidson 2025–2026 Fat Boy® FLFB
Harley-Davidson 2025 Fat Boy® Gray Ghost FLSTFI
Harley-Davidson 2025–2026 Heritage Classic FLHC
Harley-Davidson 2023–2026 Low Rider® S FXLRS
Harley-Davidson 2023–2026 Low Rider® ST FXLRST
Harley-Davidson 2023–2024 SOFTAIL FAT BOB 114 FXFBS
Harley-Davidson 2023–2024 SOFTAIL FAT BOY 114 FLFBS
Harley-Davidson 2023 SOFTAIL FAT BOY ANNIVERSARY FLFBSANV
Harley-Davidson 2023–2024 SOFTAIL HERITAGE CLASSIC 114 FLHCS
Harley-Davidson 2023 SOFTAIL HERITAGE CLASSIC ANNIVERSARY FLHCSANV
Harley-Davidson 2024 SOFTAIL HYDRA-GLIDE REVIVAL FLI
Harley-Davidson 2023–2024 SOFTAIL SPORT GLIDE FLSB
Harley-Davidson 2023–2024 SOFTAIL STANDARD FXST
Harley-Davidson 2023–2024 SOFTAIL STREET BOB 114 FXBBS
Harley-Davidson 2025–2026 Street Bob® FXBB
Touring
20 models
Brand Year Model
Harley-Davidson 2026 CVO™ Street Glide® FLHXSE
Harley-Davidson 2026 CVO™ Street Glide® Limited FLHXLSE
Harley-Davidson 2026 CVO™ Street Glide® ST FLHXSTSE
Harley-Davidson 2023–2026 Road Glide® FLTRX
Harley-Davidson 2026 Road Glide® Limited FLTRXL
Harley-Davidson 2023–2026 Street Glide® FLHX
Harley-Davidson 2026 Street Glide® Limited FLHXL
Harley-Davidson 2023 TOURING ELECTRA GLIDE HIGHWAY KING FLHFB
Harley-Davidson 2023 TOURING ROAD GLIDE ANNIVERSARY FLTRXSANV
Harley-Davidson 2023–2024 TOURING ROAD GLIDE LIMITED FLTRK
Harley-Davidson 2023 TOURING ROAD GLIDE SPECIAL FLTRXS
Harley-Davidson 2023 TOURING ROAD GLIDE ST FLTRXST
Harley-Davidson 2023–2025 TOURING ROAD KING SPECIAL FLHRXS
Harley-Davidson 2023 TOURING STREET GLIDE ANNIVERSARY FLHXSANV
Harley-Davidson 2023 TOURING STREET GLIDE SPECIAL FLHXS
Harley-Davidson 2023 TOURING STREET GLIDE ST FLHXST
Harley-Davidson 2025 TOURING STREET GLIDE ULTRA FLHXU
Harley-Davidson 2023–2024 TOURING ULTRA LIMITED FLHTK
Harley-Davidson 2023 TOURING ULTRA LIMITED ANNIVERSARY FLHTKANV
Harley-Davidson 2023 TOURING ULTRA LIMITED SHRINE EDITION FLHTK SHRINE
Trike
6 models
Brand Year Model
Harley-Davidson 2026 CVO™ Street Glide® 3 Limited FLHLTSE
Harley-Davidson 2023–2026 Road Glide® 3 FLTRT
Harley-Davidson 2026 Street Glide® 3 Limited FLHLT
Harley-Davidson 2023–2025 TRIKE FREEWHEELER FLRT
Harley-Davidson 2023–2025 TRIKE TRI GLIDE ULTRA FLHTCUTG
Harley-Davidson 2023 TRIKE TRI GLIDE ULTRA ANNIVERSARY FLHTCUTGANV

Planning other changes? Find your model in the bike customiser.

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