Master Cylinder Rebuild Question

So I have a little Yamay RT 180 that I like to mess around on..I just rebulit the master cylinder front brake and I'm having a little problem with it. I replaced the whole thing with a new spring, plunger, and seals. The brake is now always a little bit on..and when I do grab the lever it feels super tight to me. Not sure if I need to re-bleed or should I take some fluid out of the resavoir...anyone?

Thanks, RANK

What do you mean by:

"The brake is now always a little bit on.."? Is the brake dragging? How did you check? Did you raise the front wheel and spin it without the brake to see if it rotates freely?

Did you do anything with the wheel cylinder when working on the master cylinder? There could be some dirt or rust in there that is keeping the pads from retracting fully.

Did you completely replace all of the fluid when rebuilding the master cylinder? Flush the brake line and wheel cylinder? There is a chance that you got some dirt or debris in the brake line and that is contributing to your problem.

If you didn't take the wheel cylinder apart and clean it, I would start there. Make sure there is no dirt, grit or rust in there. Check the pads for any potential damage and wear while you have them out.

Then I would flush all of the brake fluid out of the system (wheel cylinder, brake line, master cylinder). Take the brake line completely off and blow it out with compressed air to make sure there is nothing in it. Completely disassemble the master cylinder and clean everything with solvent. Get everything spotless before continuing.

Reassemble everything, fill with fresh brake fluid from a new can and bleed.

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