Tight front brake caliper

[Guest]

I had the front tire on and off several times. The pads in the RF caliper are too tight to remount it. (I didn't touch the brake lever. Probably moving the caliper assembly around too much did it.)

So, how do I separate the pads enough to remount the assembly? Loosening the bleeder screw did nothing.

The bike will not be ridden until I've replaced all rubber parts in the brakes, including the hoses. That project isn't coming for another month or two. For now my goal is to not leave the caliper assembly hanging on a bungee cord.

 

[koolaid_kid]

Have you moved the piston all the way back in the caliper using a C-clamp?

 

[Colin Green]

I use a big blade screw driver to lever them apart (gently) I haven't had a stuck one yet but care would need to be taken to avoid damaging the pads.

 

[Guest]

A big screwdriver was enough to separate the pads and just barely get the caliper assembly remounted. To pull the brake pads and push the piston back it, requires that the actual caliper be removed. I don't see how I can do that without holding the assembly very tightly, such as in a vise or on the fork. So I can do it the right way when the time comes.

Thanks for the help

 

[Suzuki_Don]

A big screwdriver was enough to separate the pads and just barely get the caliper assembly remounted. To pull the brake pads and push the piston back it, requires that the actual caliper be removed. I don't see how I can do that without holding the assembly very tightly, such as in a vise or on the fork. So I can do it the right way when the time comes.

Thanks for the help

Try using a large "C" clamp and protect the painted surface of the caliper with a piece of wood (1" x 1/4"). If you are replacing the brake pads then the "C" clamp can push on the pad which is against the piston, if not then remove the pad and the screw part of the clamp can push inside the piston and push it back as you wind the clamp in. Or replace the pad with a piece of 1/4" thick wood for the "C" clamp to push against.

Loosen the master cylinder cap to allow pressure release as the fluid is forced back up the brake line. Make sure the reservoir does not overflow.

 

[duaneage]

Pop off the brake line, use rags everywhere since brake fluid is evil stuff. For really tough calipers (I've dealt with some absolute rocks before) I use a wood wedge between the pads and a clamp to force it through. Watch out for rapid brake fluid expulsions, it's the worst stuff in the world in your eyes.

 

[Big T]

I think the bike is telling you that a caliper rebuild is overdue. While you plan on doing it in a couple of months, you might as well start now so you have an idea of what needs to be done

Pry the pads apart, remove the pads, repeat on the left side. Pop the pistons out (difficult one 1st) and go from there.

I'm sure you'll find some interesting stuff in there

 

[Guest]

I already have all of the rubber parts for a complete rebuild of all cylinders. After I change the rear tire and rebuild the carbs, I'm buying new brake lines. Then I'll rebuild the entire system.

 

[Big T]

You may need pistons as well

All I'm saying is that you're taking the hard way on the brake rebuild.

Why be redundant? There's no parts to lose, save the bleeder.

Tear down the calipers now, see if you need pistons. Scrub out the calipers, which can be done with a Scotchbrite in the kitchen or utility sink. something to tide you over during the cold weather. New rubber, a bit of brake fluid and they'll be ready to pop back on when you get the new brake lines.

You may even decide to paint the calipers while they're laying around

 

[Guest]

I have too many projects going. I will not start the project of a brake rebuild until I finish others.

 

[Guest]

When you remove the wheel, use a wooden shim wedge to keep the caliper opened. If you can get them apart just a small bit' the wedge will open them if you tap it in slowly and wait a bit and then do it again. It's not really that tight, it's just a small return hole for the fluid to return to the master cylinder. so it won't move very fast. The constant pressure of a shim wedge will open them about as fast as gravity closed them. It helps to remove the reservoir cap. When you get new lines and rebuild, it's a real good time to switch to dot 4 fluid. With everything clean and nothing to contaminate the fluid, it works just as well or better than dot 3, and it won't hurt your paint at all. Get all the couplers and banjos perfectly clean too so nothing can mix.

 

[Guest]

Thanks, Old Vet. My rear wheel is coming off soon, and I'll use a wood shim with it. Switching to DOT 4 brake fluid also sounds like a good idea.

 

[GS750]

When you get new lines and rebuild, it's a real good time to switch to dot 4 fluid. With everything clean and nothing to contaminate the fluid, it works just as well or better than dot 3, and it won't hurt your paint at all.

Really? I was of the belief (20 years in the brake and clutch industry) that and dot 3,4or 5.1 strip paint as they are glycol based, dot 5 wont though because it is silicone based.