I considered putting this in the ZX section but I thought the brake specific section would be better due to all the upgrade threads.

I was wondering if anyone has tried or knows what happens if you try to use the pistons from a Tokico master cylinder rebuild kit in a Nabco MC.

looking at them side by side they are clearly different, but only just.

It make be hard to see in the photo but there are small differences in the measurements between them (dirty is Nabco, shiny/bagged is Tokico).

The overall length looks the same. I haven’t measured them yet so can’t give you precise numbers.

Edited 18 hours ago18 hr by Matthew Abate

I would think if the OD's on the pistons are similar and both brake port holes are open at rest it would probably work...

That's really a risky maneuver. Overall length isn't as important as where the seals end up located when the cylinder is at rest. It would take a lot of study and investigation to know if it would work.

Off the top of my head, looking at the rearmost piston (the one that the master cylinder pushes against), it has the seal in a different location than the original. The front piston is harder to analyze since it depends on where the seal will end up when the stop screw hits the lip of the piston.

I'm just a guy with a keyboard, but I don't like it.

The stop screw catches the rear (left in photo below) piston in the narrower part between the seals, right?

I noticed that space on the Tokico kit (bottom) is longer than the Nabco version (top). There’s also more fluid in that area because the piston is narrower there.

The front (right in photo) piston is also narrower on the Tokico, but otherwise those are really similar in length. Virtually the same.

I wonder if the Tokico works in the Nabco but not the other way around.

Edited 6 hours ago6 hr by Matthew Abate

The stop screw catches the front piston like this:

And the rear piston position is established by the retainer clip in the back:

So the distances between those two reference locations and the "forward-most" seals on each piston is what's important. It looks like the front piston is really close, but the rear one is not. Might be "close enough", might not.