Dragging front brake pads!

[schrader7032]

A couple of things come to mind:

1) Have you aligned the pads in the caliper? There is an eccentric pin inside that caliper that changes the pads relative to the disk. The pin is accessed through the hex cap on the underside of the caliper. To visualize how the pad is contacting the disk, use a magic marker to put a mark radially on the disk, turn the wheel while slowly actuating the brake. You want the mark to be evenly cleaned off. Here's a picture fromr a /6 rider's manual that shows the pin and what to do about it:

http://www.pbase.com/dwerbil/image/74356091

2) The brake caliper may be in need of an overhaul. Corrosion may have built up in the caliper, preventing ease of movement.

3) Is the brake hose the original rubber hose? It may be breaking down internally, swelling when in use. The swelling doesn't permit the retraction of the pads after you let off the brake handle. Replace it. I prefer the stock hose; others like to go to stainless brake lines. The stainless is supposed to provide better feel and braking action...it can also easily damage fender paint.

4) The small hole in the master cylinder under the tank may be blocked, not allow fluid back into the master cylinder after you release the handle. You push the fluid out to the caliper and when you release it and the caliper wants to move back (due to being hit slightly by the rotating disk), that fluid has to go somewhere. You may need to rebuild your master cylinder.

5) Try bleeding your brakes. Should be done routinely to keep water out of the internals of the system. Water can create corrosion. Don't use DOT 5; using only DOT 3/4.

6) Make sure the actuation lever at the master cylinder is adjusted properly. There is a specific measurement for the small piston at the end of the cable that actually pushes on the internal piston in the master cylinder.

Here's an article on the Airheads website about ATE brakes. Joe Cuda wrote this...he's very good at getting the most out of ATE brakes.

http://www.airheads.org/content/view/184/98/

Sounds like you need to start on the easy stuff first and work your way up to make sure the brakes are working correctly.

Kurt in S.A.

[drax]

Wow! Kurt, thanks for your quick and thorough reply to my posts.

1) I did mess with the alignment of the pads in the caliper before posting (based on Haynes), but it didn't work--still drag and squeal. I did not, however, use anything like a magic marker, so maybe I should try it again. It just seems like a return spring/mechanism of sorts isn't working well enough to pull the pads back from the disc.

2) an overhaul is the next step (after steps #1, #5 and #6).

3) the brake hose was replaced by the prior owner to a stainless line.

4) I'm letting my gas get low in the tank in anticipation of removal for a master cylinder overhaul as well.

5) & 6) I will try these steps before committing to a total overhaul. DOT 3/4--got it!

In the next week or so I should have some time to mess with it. I'll post a follow up. Thx again!

[schrader7032]

It just seems like a return spring/mechanism of sorts isn't working well enough to pull the pads back from the disc.

There's no such return mechanism for these brakes...not even your car brakes that I know of. I think there are only a couple of ways for pulling back the pistons. I think primarily the turning disk and its irregularities will actually push the piston back...it only has to go back just a bit. But in order to do that, the fluid behind the piston has to go someplace. Hence needing to return to the master cylinder. If the piston doesn't slide back and forth very well, then it will tend to remain in position. There's a rubber o-ring/seal that the piston rides on in the bore of the caliper. It might be that the side of the piston has gotten corroded and won't slide anymore...could be in the process of cutting the seal, leading to brake fluid leakage.

Kurt in S.A.

[VBMWMO]

On my '77 75/7 the front brake pads are dragging on the disc. When I spin the wheel it goes about 1.5 revolutions before stopping due to the drag. I also get a squealing noise from the brakes when I ride. Any help would be appreciated! thx