Master cylinder bore?

[scooter paul]

What's the bore size of a standard R80 G/S master cylinder please?
Paul.

 

[scooter paul]

I got off my backside and looked myself, it's a 13mm. Interestingly my R80st has a 12mm. I would have thought they were the same.
Paul.

 

[Beemerboff]

My 85 G/S had a 12 mm when I bought it, but no telling who fitted it
My local guy always sleeves them down to 11mm anyway, but a 12 mm will lock the wheel with the OEM caliper, HH pads and a oversize disk.

 

[ChasF]

My 13mm mc and standard disc will lock the wheel if I pull hard enough!

 

[Colt]

standard is 13mm on g/s and r80st I thought.