front brake trouble

When I got the bike last year the front brakes had "frozen" up. I rebuilt the calipers (new seals,dust rings and pads) and they seemed to work fine for the limited riding I did after getting the bike running.

Long story short .... I went to get it out of storage this week and the front brakes are "froze"up again. I put the bike on the center stand and the back wheel is free but the front won't spin freely. It's like they are not releasing when I release the brake lever. I'm going to have to force them open just to get the bike to move then try (about 5 miles) with only the back brake or load it into my pick-up (not fun for a one man crew) to get it home.

How does the system work...Does the hydraulic pressure release enough for the pads to move back on their own or is it a matter of "wearing down" the pads to allow a free spinning of the wheel?

Is this a call to do a re-rebuild of the calipers or should I go straight to the master cylinder? I also did not touch the anti-dive (other than to bleed) could it be a problem with them?

 

I've seen this before. Take off your master cylinder, you are going to have to disassemble it pulling the plunger as well, and spray it out really good with Brake parts clear and hit it from every direction with compressed air.

What happens is inside the plunger housing to the resevoir, their is a miniskewl hole that releases the squeezed pressure from the plunger to allow fluid to release back up into the resevior and the plunger cylinder will hold an amount of brake fluid too. All it takes is a very tiny, and I mean tiny grain of a pebble or blockage of some kind to keep that release of fluid from coming back up into the master cylinder, more over acting like your lever is constantly being pulled.

Release a little fluid from the bleeder on a caliper and you should be able to roll your bike again, until you can get to it.
Goodluck

 

define..... won't spin freely
disk brakes always have some drag, especially if they've sat for a few months

 

Not able to complete 1 full time around when the bike is on the center stand and front wheel is in the air.

There had been 2 of us trying to push the bike to get it out of the shed it is stored in and we could not move it more than 25 feet(on the level we gave up trying to get it to go up the hill). It is not the normal drag that disk brakes have.

 

The front caliper needs to "Travel" along these two shafts which must move in and out within these two small cylinders.

Overhaul the mount. Clean-out the two cylinders and refinish the bore by twisting some medium steel wool stuffed in there. Change to fine steel wool after all the oxidation is removed.

The shafts have dust covers and O-rings. Be careful with the dust covers. The 0-rings are easily replaced if needed.

Shine and apply a new finish to the shaft by using 400, 600, 800, and 1000 WetODry strips in a "Shoe-shine type" fashion. Get the surface of the shaft looking brand new.

Lube the inside of the bore and the outside of the shaft with high-quality synthetic waterproof grease.

Join the assembly and "Burp-out" the air bubble so that the caliper travels freely along the overhauled shafts.

 

Rick
I'm not sure what shafts you are referring to. I know what you are talking about but when I had the calipers off the only shafts I saw held just the pads in place not the calipers.

Is that diagram for a 1983 900seca because mine looked different hears a look at what they are like.