Brake cylinder

[TimBell1962]

I read a few older posts about wooden feeling brakes (single disc) and replacing the cylinder with a 13mm. Is the cylinder fitted to mine standard as I didn't rebuild it and its not all standard? The caliper is a Grimeca, no markings on the cylinder, Brembo markings on the lever.

20251215_135118.jpg (493.69 KiB) Viewed 69 times

[Steve Brown]

No, that's not a standard master cylinder. Most were Grimeca and I think a few had Brembo? Either of those would be branded. If the one you have is Japanese it may well have the bore size in mm cast or stamped on it, usually underneath.
If your brakes don't feel 'wooden' and they have a little 'give' and feel quite reasonably powerful , you might have a smaller than standard cylinder bore there.