Topic: Front Brake Question

[Accolay]

1977 CB550F. I'm having one heckuva time getting this front brake to work. I think I've read just about every brake post in this forum. I'm pretty sure I have figured out how to bleed this sucker. I think.

However, my problem is caliper A sticks to the rotor and will not return. Today I got a brass wheel for my dremel as mentioned on the forum, and I cleaned out the square groove. Got a little more stuff out of there, but not much. I've oiled the caliper holding pin to make sure it pivots, and it seems to. I'm using EBC brake pads.

The old pad on caliper A had this plastic ring between it and the piston. Should I be using this on the new pad? The new one did not come with one. I'm wondering if this will change the clearance and get rid of my problem. I want to experiment and see, but I also don't want to take the caliper apart again.

Also, how stiff should the MC handle feel when it's happy?

Thanks

[Accolay]

I forgot to mention a few other things: I have rebuilt the MC with new parts. New SS brake lines/bolts/copper washers from HEL. I used the existing piston in the caliper-it had very minor pitting. New piston oil seal and a new Speed Bleeder.

When I open the bleeder, caliper A does not let go of the rotor.
Something is amis then: I can get the MC handle to come all the way back to the handle. Still air in the system I guess? I've tried bleeding the thing over four days, letting it sit, pumping slow, pumping fast, praying to the motorcycle gods etc. and even disconnected the MC from the handlebars and the three way oil joint from the bike and tried to straighten the lines out to let any air bubbles find there way out easier.

What am I missing? What am I doing wrong? I hate to say it....but I'm almost ready to pay that 80$ an hour charge to drive it over to the local honda shop to have them abuse it for me. But I can't do that...not quite ready to throw in the towel yet.

[Blueridgerunner]

When I did mine, I cleaned EVERYTHING up really well. I did use caliper grease on the sliding portions of the assembly as well. I too, put a speed bleeder on.

[Honda_Nut]

When I got my bike, the front was dry. After filling and bleeding, it stuck. I cleaned the piston and put it back together and it was mushy/sticky after bleeding it four times. I took it back apart and found that the plastic ring you mention was in there cock-eyed and causing my problem. I doubt this helps you, but if someone else who made the same mistake I did reads this, it could help.

Are you completely sure all the air is out? Spongy and sticky usually means air. BTW, mine's rock hard at just about 3/4 pull now.

[super pasty white guy]

Are you sure that you've got it bolted up right?  One time I had the fender brace wrong and the brake would jam up.

Doh!

spwg

[Accolay]

To add insult to injury, my caliper adjusting screw broke. I'm turning it with pliers until the new one arrives.

I also cleaned everything in this rebuild. I soaked the caliper MC and oil joint in denatured alcohol for a few days, then used 0000 steal wool on some of the aluminum surfaces and blew everything out with air. I forgot that I also got a new little hose/pipe from the caliper to the new SS connections. I used dow high vacuum grease on the back of the pads and O'Reilly Dot 3 Brake Fluid. The only things that are original are the master cylinder, three way oil joint and the calipers. The only thing I couldn't find (locally) was brake parts assembly lube. I just coated the inside parts with a film of new brake fluid for assembly.

SPWG: Am I sure I've got it bolted right? My friend, I am sure of nothing!  I can definitely check that, but I want to think I have it right. I can pump on the handle, and the piston comes out- I can even hear a faint squeaking from the caliper holder moving when pressure is applied, but then caliper A doesn't come back. The caliper A pad drags on the rotor when the wheel is spun.

I guess I'm going to try and disassemble the caliper holder to oil it up to make sure it's happy and see if the three way joint is ok.

The caliper holder with its spring puts pressure on the caliper A pad. Is this correct? Anyone know if I have to use the ring between the caliper pad and the piston?

[Accolay]

Well...I disassembled and cleaned out the caliper holder pivot. It wasn't too bad, but new grease doesn't hurt anything. I think I'm going to leave the ring between pad and piston there. It doesn't make sense that it would change any clearance issues...or at least I can't think of any issues.

To the garage!