Topic: CB550 Front Brake Setup question.

[midwrestless]

Hey everyone,

First time posting on here. I recently decided to replace the entire front brake setup (caliper, master cylinder and brake line) on my '76 CB550. I bought all the parts from 4into1 that were compatible and all seemed well until I added brake fluid. I bled the brake line until I saw fluid come through the line and the bubbles stopped. After tightening the drain valve and capping the cylinder, I pumped the lever and felt the pressure of the fluid. Problem is that the caliper won't release now. Any idea what I did wrong or why this is happening? I'm new to the process and could easily be making a simple mistake that I'm not noticing. I couldn't find much instruction for adding fluid and setting up a brand new line. Thanks!

Caliper - http://4into1.com/front-brake-caliper-assembly-45100-390-405-assembled/
Master Cylinder - http://4into1.com/replica-kawasaki-complete-brake-master-cylinder-use-on-honda-too-14mm/
Brake Line - http://4into1.com/stainless-steel-brake-line-kit-clear-single-line-honda-cb400f-cb550f/

[calj737]

It is possible that the pad on the outboard side is stuck in the caliper body due to some paint around its edges. If the fit (pad to caliper) is too tight, the pad not retracted when sufficient pressure pushes the pad out completely (you won't discover this while bleeding, only after full pressure is developed).

To remedy this, you have to unbolt the caliper halves from the retaining arm, remove the piston on the left side (the interior pad is static) and gently remove any paint.

Normally, I'd suspect the piston seal, but given that this is an entirely new caliper (assume it came assembled) theres little chance of that being the issue. Be careful reassembling the caliper bolts, they are very fine thread and will easily cross thread into the caliper.

See if that helps-

[CBGhia]

To remedy this, you have to unbolt the caliper halves from the retaining arm, remove the piston on the left side (the interior pad is static) and gently remove any paint.

I think you mean brake pad here.   Yeah, hit the edges with a dremel sanding wheel to clean it up some.  Don't go nuts with it.

[Kenzo]

What they said and...

The piston really never retracts...it's more of a "clamp" when you apply pressure at the master(brake lever) and "float" when you release. When you release the brake lever do the pads remain clamped where you can't turn the wheel by hand or are the pads just dragging?

Cheers,
Kenzo

[DH]

the caliper bracket is "hinged "and if the hinge is frozen, the bracket won't move when
the brake is applied  or released. Maybe not the problem at this time, but a good idea to remove it and pull the pivot pin
to clean the pin and lubricate it. the bracket should swing freely when mounted and working properly.
This will affect operation and will allow proper adjustment as well. just to add to what has already has been suggested.

[calj737]

I think you mean brake pad here.

Yes I did, thanks for catching that.

[midwrestless]

I can't move the wheel without a lot of force. When I am pulling the break lever, I can't move wheel at all, when I release it, I can move the wheel only by applying a lot of force. No free spinning whatsoever.

[jonda500]

If you have new pads, maybe they are a whisker too thick? Does it work properly if you slightly loosen the two calliper bolts?
John

[midwrestless]

If you have new pads, maybe they are a whisker too thick? Does it work properly if you slightly loosen the two calliper bolts?
John

I'm thinking that this might be the case. Has anyone else encountered this with new pads? I could ride the motorcycle, there's just slight resistance. They're floating but maybe dragging a bit much because they're new?

[calj737]

Sand the edges of the pads. This is a common problem with aftermarket pads, and it prevents them from retracting fully. Its pretty simple really... 

[jonda500]

My new aftermarket pads (after sanding off all the black paint so that it slipped into the calliper easily) were grabbing the disc after I bled the brakes. They weren't dragging too bad - I could still push the bike around - I rode it around the block a few times doing some heavy brake applications. When I got back the problem was gone!
John

[sammermpc]

Also, don't expect your front wheel to be 100% drag-free even when you do get it right. If you're just spinning your front wheel by hand, you'll still detect some drag. That's normal. The clearances with the rotor are very tight.

Here's a  thread where it's discussed: http://forums.sohc4.net/index.php/topic,142276.msg1614073.html#msg1614073. 

[midwrestless]

This was definitely the case!!!! Running great, thanks for this.