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500855 Rear master cylinder rebuild kit, Kelsey-Hayes

Fits: 79-81 XL Sportster; 79-84 FL; L79-8…
79-81 XL Sportster; 79-84 FL; L79-83 FX; 80-85 FLT/Touring
OEM: 42374-77B
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£9.86

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Estimated delivery: 3–15 working days

Part #: 500855 | Pack: KIT

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Specifications

Brand
MCS
Part Number
500855
OEM Reference
42374-77B
Pack Quantity
Sold as kit
Category
Master Cylinder Rebuild Kits
VAT Rate
20%

About This Product

If your rear brakes are feeling spongy or sticking, this master cylinder rebuild kit is exactly what you need to get things back to factory spec. It’s designed for the 3/4-inch piston Kelsey-Hayes style master cylinders found on several classic models. This kit fits 1979-1981 Sportsters, 1979-1984 FL models, late 1979-1983 FX models, and 1980-1985 FLT Touring bikes. It is a high-quality reproduction of the OEM 42374-77B kit. Sold as a complete kit, it includes the necessary components to refresh your master cylinder internals, ensuring reliable hydraulic pressure and consistent braking performance for your vintage Harley.

Manufacturer part number: 500855.

Fitment

62 models

79-81 XL Sportster; 79-84 FL; L79-83 FX; 80-85 FLT/Touring

Cafe Racer
1 model
Brand Year Model
Harley-Davidson 1977–1978 Sportster 1000 XLCR-1000
Electra Glide
14 models
Brand Year Model
Harley-Davidson 1979–1980 Electra Glide FLH-1200
Harley-Davidson 1979–1980 Electra Glide FLH-80
Harley-Davidson 1980 Electra Glide FLHS-80
Harley-Davidson 1984 FLH Police 80 FLH
Harley-Davidson 1979–1980 Glide Classic FLHC-80
Harley-Davidson 1981–1984 Police Electra Glide FLH-1200
Harley-Davidson 1981–1984 Police Electra Glide FLH-80
Harley-Davidson 1983 Police FLH
Harley-Davidson 1979–1980 Police FLH-1200 FLH-1200
Harley-Davidson 1980 Touring Electra Glide Classic FHL-80
Harley-Davidson 1979 Touring Electra Glide Classic FLHC-80
Harley-Davidson 1980 Touring Electra Glide FL-80
Harley-Davidson 1979–1984 Touring Electra Glide FLH-80
Harley-Davidson 1980 Touring Electra Glide Sport FLHS-80
FXR
8 models
Brand Year Model
Harley-Davidson 1989–1990 FXR Convertible FXRS
Harley-Davidson 1985–1986 FXR Custom FXRC
Harley-Davidson 1984–1986 FXR Low Glide FXRS
Harley-Davidson 1986–1993 FXR Sport FXRS-SP
Harley-Davidson 1986 FXR Super Glide FXR
Harley-Davidson 1986 FXR Touring FXRD
Harley-Davidson 1984 FXR Touring FXRDG
Harley-Davidson 1984–1990 FXR Touring FXRT
FXR Police
1 model
Brand Year Model
Harley-Davidson 1984–1995 Police Low Rider FXRP
Low Rider
2 models
Brand Year Model
Harley-Davidson 1979 FX Super Glide FXS-1200
Harley-Davidson 1979–1980 FX Super Glide FXS-80
Police Electra Glide
1 model
Brand Year Model
Harley-Davidson 1979–1980 Police FLH 80 FLHP-80
Roadster
1 model
Brand Year Model
Harley-Davidson 1979–1980 Sportster 1000 XLS-1000
Softail
7 models
Brand Year Model
Harley-Davidson 1983 Dyna Glide Glide Custom FXDG
Harley-Davidson 1983–1984 FX Low Rider FXSB
Harley-Davidson 1981 FX Super Glide Fat Bob FXEF
Harley-Davidson 1981–1984 FX Super Glide FXE
Harley-Davidson 1981–1982 FX Super Glide FXS
Harley-Davidson 1981–1984 FX Wide Glide FXWG
Harley-Davidson 1981–1982 Super Glide B80 FXB
Sportster
3 models
Brand Year Model
Harley-Davidson 1981 Sportster 1000 XLH
Harley-Davidson 1979–1980 Sportster 1000 XLH-1000
Harley-Davidson 1981 Sportster Roadster 1000 XLS
Super Glide
5 models
Brand Year Model
Harley-Davidson 1979–1980 FX Super Glide Fat Bob FXEF-1200
Harley-Davidson 1979–1980 FX Super Glide Fat Bob FXEF-80
Harley-Davidson 1979–1980 FX Super Glide FXE-1200
Harley-Davidson 1983–1984 FX Super Glide FXS-80
Harley-Davidson 1980 Super Glide B80 FXB-80
Tour Glide
3 models
Brand Year Model
Harley-Davidson 1979–1980 Tour Glide FLT
Harley-Davidson 1980 Touring Tour Glide FLT
Harley-Davidson 1983 Touring Tour Glide FLTD
Touring
15 models
Brand Year Model
Harley-Davidson 1981–1983 Electra Glide FLH
Harley-Davidson 1981 Electra Glide FLHS
Harley-Davidson 1983–1984 Electra Glide FLHT
Harley-Davidson 1981 Glide Classic FLHC
Harley-Davidson 1983–1984 Glide Classic FLHT
Harley-Davidson 1981 Glide Classic FLTC
Harley-Davidson 1982–1984 Tour Glide Classic FLT
Harley-Davidson 1981–1984 Tour Glide FLT
Harley-Davidson 1981–1982 Touring Electra Glide Classic FLHC
Harley-Davidson 1983–1985 Touring Electra Glide Classic FLHTC
Harley-Davidson 1984 Touring Electra Glide FLH
Harley-Davidson 1981–1984 Touring Electra Glide Sport FLHS
Harley-Davidson 1983 Touring Electra Glide Standard FLHT
Harley-Davidson 1980–1985 Touring Tour Glide Classic FLTC
Harley-Davidson 1981–1983 Touring Tour Glide FLT
Wide Glide
1 model
Brand Year Model
Harley-Davidson 1980 FX Wide Glide FXWG-80

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Who are we? Leeds Harley-Davidson - Iron City Motorcycles

Who are we? Leeds Harley-Davidson - Iron City Motorcycles

This product is fulfilled by Iron City Motorcycles, Leeds' authorised Harley-Davidson® dealer, serving the UK with a full range of Genuine Motorclothes®, dealer merchandise, and official Harley-Davidson parts & accessories — available for UK and international delivery.

From OEM Parts to retro lifestyle wear to aftermarket stockits we have what you need to keep you riding all year round.

Use our official OEM parts finder to browse our full Genuine Harley-Davidson® Parts and our associated approved aftermarket catalogues.

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