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J&P Cycles® Master Cylinder Rebuild Kit

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Product may vary from photo(s).

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J&P Part: 2400390

Rating: Read Reviews


Instructions 2400390.pdf

J&P Cycles® Master Cylinder Rebuild Kit

• Meets or exceeds OEM specifications

• Includes metal piston

• For 3/4″ bore master cylinders

• Replaces OEM 45063-72

Product Specs

  • Bore Diameter: 3/4″ bore
  • Cylinder Bore Size: 3/4″ bore
  • Kit: Yes
  • OEM Reference: (OEM 45063-72)
  • Position: Front
  • Sold in Units: Kit


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Harley-Davidson® Models

Electra Glide Anniversary FLH : 1978
Electra Glide Classic FLHC : 1979–1981
Electra Glide Classic Side Car FLHCE : 1979–1981
Electra Glide FLH : 1972–1978, 1981
Electra Glide FLH-74 : 1979–1980
Electra Glide FLH-80 : 1978–1980
Electra Glide FLHF : 1972–1975
Electra Glide Heritage FLH : 1981
Electra Glide Police FLHP : 1981
Electra Glide Police FLHP-74 : 1979–1980
Electra Glide Police FLHP-80 : 1979–1980
Electra Glide Police FLP : 1972, 1974–1975
Electra Glide Police FLPF : 1972
Electra Glide Sport FLHS : 1977, 1980–1981
Low Rider FXS : 1977–1978, 1981
Low Rider FXS-74 : 1979–1980
Low Rider FXS-80 : 1979–1980
Sportster 1000 Café Racer XLCR1000 : 1977–1978
Sportster 1000 Electric Start Anniversary XLH1000 : 1978
Sportster 1000 Roadster XLS1000 : 1979–1981
Sportster 1000 Touring XLT1000 : 1977
Sturgis Belt FXB : 1980–1981
Super Glide Electric Start FXE : 1974–1981
Super Glide Fat Bob FXEF : 1980–1981
Super Glide Fat Bob FXEF 74CI : 1979
Super Glide Fat Bob FXEF 80CI : 1979
Super Glide Kick Start FX : 1973–1978
Touring Tour Glide Classic FLTC : 1981
Touring Tour Glide FLT : 1980–1981
Wide Glide FXWG : 1980–1981

Customer Reviews

 handysteve36 Posted:

Perfect rebuild kit for my vintage Electra Glide. Easy to set up. Works great. Highly recommended. Posted:

Worked fine, I used all the included parts. No leaks.

 gitche Posted:

Nice fit, easy rebuild with all necessary parts.

 mikewitt Posted:

This is a perfect fit. Much better than the same kit two years ago. On my 78 stock cylinder even felt fits nice. Always a tricky fix - or maybe I am just better. Buy it.

 DarkXstar Posted:

good kit does what it suppose to do. The return spring could be a little stronger.

 jeezlouise Posted:

it's a cheap kit but often the mastercylinder is just worn too much..

 leggsy Posted:

Worked well. Does not come with a new circlip though.

 harley61855 Posted:

got the job the first time

 enipper Posted:

Fast and dependable, also very helpful in the tech area. thanks J&P

 washley Posted:

perfect fit Posted:

Piston was milled wrong. Itwas out of round Had to put old one back in

 mtneerfans Posted:

Worked like a dream needed nothing.

 gtrepko Posted:

The new piston did not fit into the bore, wouldn't even start. The snap ring is too thick, would not fit into the groove properly. Had to re-use the old parts.

 Lance.gardiner Posted:

Fits and works just right

 roush360r Posted:

very nice kit, although it wouldve been nice if it came with a cover gasket.

 1930VL Posted:

gotta have it....

 walterleon3 Posted:

good kit, good price

 hocks22 Posted:

No problems,looks good and fitted fine.

 62duoglide Posted:

Worked great!

 reklawpj Posted:

Spring was way too soft, had to use the old spring.

 molley21 Posted:

work great

 bpc4035 Posted:

While the kit picture shows the seal for the cover it was not included. Also the plunger will not fit without modification. Poor quality construction.

 laddiemac1 Posted:

compared to the oem part...the spring is not up to par....too weak... needs to be thicker ....also the fiber gasket is thicker than the orignal hd part....

 supr2nr Posted:

Works great and great price. Everyone is right though the spring is a bit to weak so I had to use the original one as well.



 sws802 Posted:

Used this kit on a 1980 Sportster that I rebuilt. Everything was great about the kit except the return spring was a little weaker than the original and wasn't functioning quite right. I used the original spring and everything works great.

 cliffaddison Posted:

Sealing parts worked correctly but return spring was too weak had to use original.

 43king Posted:

Spring is to weak.

 vileija Posted:

The return spring was not strong enough to push the piston back. I had to use old spring which is much stronger and thicker then the one in the kit. All the other parts in the kit were good.

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