[captng1]

Hi Guys,
A Merry Christmas To All! So my rear brake has been dragging. I removed and rebuilt the rear caliper with new pistons, seals, and pads, cleaned and greased the guide bolt and sleeve, replaced the rubber brake hose, removed the master cylinder and ran a thin piece of wire through the relief hole (seems to be clear), installed new fluid and bled, and brakes are still dragging! I guess at this point it is time for a new master cylinder? Seems to be the only thing left? Your thoughts?

 

[Bike...and Dennis]

Can you tell which side it's dragging on?

Maybe a pin is sticking.

Or a bent mounting plate.
.

 

[captng1]

Can you tell which side it's dragging on?

Maybe a pin is sticking.

Or a bent mounting plate.
.

It only has one rear caliper, but if you mean on which side of the rotor, I couldn't say? Pin is greased and free. It seems now it is also making the right front bake drag as well, which tells me it is the master cylinder. Anyone know of an aftermarket shop that sells them? Wing stuff doesn't appear to have them...

 

[tinman38]

dragging brake update

rebuild m/c there are kits online. Good luck :smile2:

 

[captng1]

rebuild m/c there are kits online. Good luck :smile2:

Thanks. Not sure rebuilding will fix it if the internal hole has an obstruction in it? The seals and all seem fine as it does build up pressure when pumped. Just doesn't release the pressure. Thinking Id just rather buy a new one than waste any more time on this...

 

[Pure Texas]

One side is stationary,could a spacer be in wrong?
Can you post a picture of how it’s installed.
O never mind after reading your post again,did you clean the inside of the caliper and lube the piston on assembly?

 

[Bike...and Dennis]

Though I don't think you need it, this one seems like a pretty good deal.

https://www.ebay.com/itm/1984-Honda-Goldwing-1200-Gl1200a-Rear-Brake-Master-Cylinder-OEM/401456278750?hash=item5d78a8acde:g:xHQAAOSwnDpaKeAt

 

[Ken Bergen]

......... installed new fluid and bled, and brakes are still dragging! I guess at this point it is time for a new master cylinder? Seems to be the only thing left? Your thoughts?

As you can bleed the brakes the feed/return hole is clear.

 

[captng1]

One side is stationary,could a spacer be in wrong?
Can you post a picture of how it’s installed.
O never mind after reading your post again,did you clean the inside of the caliper and lube the piston on assembly?

Hi Pure Texas,
Yes, caliper was cleaned inside and piston installed with fresh brake fluid. Thanks..

 

[captng1]

As you can bleed the brakes the feed/return hole is clear.

Hi Ken,
Not sure how you get to that conclusion? When bleeding the brakes, you are pumping fluid down the main tube and releasing it out the caliper. The return hole is not in use when sending fluid "To" the caliper or pressing Down on the pedal. as I understand it, it is only in use when the pedal is released? If in fact it is clear, then I am really stuck on why my brakes are dragging? I have done everything I can think of!...

 

[captng1]

Though I don't think you need it, this one seems like a pretty good deal.

https://www.ebay.com/itm/1984-Honda-Goldwing-1200-Gl1200a-Rear-Brake-Master-Cylinder-OEM/401456278750?hash=item5d78a8acde:g:xHQAAOSwnDpaKeAt

Thanks Dennis,
I'm guessing there are no After Market shops that sell new ones? I hate to buy a used one off ebay and have the same problem...

 

[Ken Bergen]

Note that I said

feed/return hole

 

[captng1]

Note that I said

Yes Ken,
I can bleed the brakes, but I believe the small relief port in the master cylinder has a problem although I have run a small piece of wire through it? Brakes are still dragging, and I'm out of ideas at this point other than replacing the master cylinder..

 

[PAPete]

I'm out of ideas at this point other than replacing the master cylinder..

Before you replaced the seals, are you sure you completely cleaned out the grooves that they fit into? Absolutely no white gook in there? Also did you lube the seals, the pistons and their places in the caliper with brake fluid? I had a similar situation once, and that was the problem.

 

[captng1]

Before you replaced the seals, are you sure you completely cleaned out the grooves that they fit into? Absolutely no white gook in there? Also did you lube the seals, the pistons and their places in the caliper with brake fluid? I had a similar situation once, and that was the problem.

Yes PaPete,
I did all of that.
Thanks

 

[81MarineE5*]

Had a 750 supersport that had all calipers rebuilt.when they reinstalled calipers on rear they left the shim washers off one caliper bolt it caused caliper to drag took weeks to figure out .

 

[redwing52]

The problem might be the master cylinder. There is a spring that makes the piston return all the way. If there is an issue with that spring the piston won't return and it can block that little hole keeping pressure on the brakes. Other things can cause the issue. Are you sure the pedal is returning to the top. The pedal must move free in it's travel all the way to the top and the spring must be in good shape. See attached.
Might try to ride the bike until the brakes start to drag. Put the bike on the center stand to see if you can rotate ech wheel by hand. If you can't rotate then try to open bleeders. Do you get pressure and the wheels rotate free now? Then you know it is a master cylinder, hydraulic or hanging pedal issue.

 

[DaveO430]

Is the front also dragging? The rear and the front, don't remember left or right, are linked together. If both are dragging the problem would be the master cylinder, if only the rear it may be the rubber hose.

 

[redwing52]

To add to what Dave said also possible pedal linkage problem if it does not return all the way. Anything is possible on a 33 year old machine. Especially if it sat for some time.

 

[MysticFour]

I had that problem once, the foot brake had rust on the post not allowing it to return fully, figured it out by putting te under pedal and lifting it