Master Cylinder Differences

[Shipper]

My original M/C has a piston 65mm long. All sites seem to say the refit kit piston at 53mm will work. How can this be and what will the 12 mm less mean to performance? Any ideas? Its a 75 650xsB

Getting real excited about firing it up but need a solid front end.

Shipper

 

[tadd442]

I'd like to know as well....that's the same recommended rebuild kit for my XS2.

 

[Dustproof]

Logically speaking, unless you change the area of the face of the piston, it should not make any difference. It just means that there will be more fluid behind the piston because it's shorter, the bore diameter of Master Cylinder and Calliper hasn't changed, this is what gives you the ratio to apply pressure for best grip of the rotor.