Do I need a brake rebuild? Problem inside

[Hucker]

I went to go replace my front pads lastnight and everything went great until I had to put the wheel on. Those new pads were awful tight, so I took apart the brake and squeezed down the pistons in order to have maximum clearance for the new pads. After opening the resevior on the bars, I pushed the pistons in almost all of the way. I knew oil would come out of the resevior so I was ready for that. After pushing the pistons back, and putting the wheel back on I had this problem. The bike would brake fine, but for some reason the pistons would not retract back enough to let the wheel free-spin. I bleed the brakes and made sure there was no air in the system. Now I might have screwed up, but I have bled brakes on a car nurmerous times and its pretty much the same system. My Clymer manual says that I might need new seals on the pistons???

Has anyone had this problem? Could it just be that I didn't bleed it correctly, or should I just go get a rebuild kit for the front brake and be done with it. Its a dual piston setup, like 99% of the 125/250's out there. Any help would be appreciated because this one has me stumped...

Thanks :)

 

[RM_guy]

You may have gotten dirt in between the piston and the piston wall in the caliper and it is preventing to piston from retracting at all.

Try this:
- Remove the rotor and pads and activate the brakes so the piston is exposed.
- Thoroughly clean the piston and caliper with brake cleaner.
- Push the piston back into the caliper and reassemble the pads and rotor.
- Keep an eye on the fluid level in the reservoir so as not to suck air or overflow it.

Good luck

 

[Hucker]

Thanks for the reply, so basically just lube up the piston with some brake cleaner and see if that gets it unstuck..

I'll give that a try.

 

[RM_guy]

You’re not “lubing” the piston. You’re just trying to dislodge and debris that might be in there.

 

[Hucker]

In the manual it shows how to actually take the piston's out. Should I do that just to be safe? And give it a good once over?

 

[RM_guy]

That wouldn’t be a bad idea if you feel comfortable doing it. When you have it apart look for damage to the seals, piston and bore.