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JeramyN wrote:I recently replaced the front brake pads on my 1977 R100/7 and they squeak like crazy. They are actually worse when not being applied so i'm guessing I have too much drag... Either way, should a little to much drag squeak like that?
Also, can the drag be adjusted by the brake lever end of cable? At the caliper? Or can it ONLY be adjusted at the master cylinder? Trying to avoid this as my fuel lines are on so tight i don't want to mess with them but i'm willing to do whatever it takes.

I cleaned the disc with scotch brite and brake cleaner and it fixed the squeak but only temporarily.

Thanks in advance

The drag is not adjustable. The pads on a disk brake are supposed to lightly ride the disk all the time. if the caliper pistons are not retracting then the pads will ride heavily. Result is more wear, less power and worse fuel mileage.

There are a ton of products to reduce pad squeal. Most of them are lubricating goops that go on the back of the pad. Get some---little one use packet at the counter in the auto parts store. it's a very high temp lube, I'd use the commercial stuff.

On the ATE brake, first step is to tune it perfectly. Pivot pin smooth, lubed. Caliper parallel to disk. Chamfering the pad as mentioned might help, but it's a very small chamfer, maybe 1/16" @ 45*. Check the contact with the stripes-of-marker routine. Stripes should radiate outwards from the center of the disk about ever inch or two all the way around the disk. A very light application of the brake while you spin the wheel by hand can reveal much. You are looking for the pads being cocked top to bottom and for warps in the disk.

The pins the pads ride on need to be nice and smooth. No surface rust. A film of lube won't hurt---but only a film. Must be high temp stuff.

New pads need to be broken in. They have to wear to match the grooves and whatnot in the disk. Use them vigorously. Depending on the compound, this can take a while. Expect less braking and more noise until they are bedded.

Your fresh pads are thicker than the outgoing worn ones. So the resting position of the caliper piston is different (deeper) than it was. This might take some breaking in too---or it could be a problem if there is roughness in the bore back where the piston is working now. Wait until the pads are bedded before worrying about it (unless you see leaks).

Put a washer on the petcock nipple ahead of the fuel line. Use Stainless. (hardware store) The "soft" side of the washer should face the line. To remove the line you push on the washer. This pushes the line off. When you push, the line puffs out and gets bigger. When you pull on the line it elongates and gets thinner, gripping the nipple tightly. On a right angle petcock, support the petcock in the crook of one finger when removing the line. With 1/4" line it's still tight, but not fearsome.

I'm not sure what the fuel line washer suggestion is doing in this discussion of his brake problem, but it is a GREAT idea which I am going to use. Like most great ideas, it's so obvious that one thinks "well, yeah, I coulda thought of that," but I didn't.

Jeramy, don't get this confused with having anything to do with your brakes, but it's still a great idea.

Major Softie wrote:I'm not sure what the fuel line washer suggestion is doing in this discussion of his brake problem....

JeramyN wrote:.... Trying to avoid this as my fuel lines are on so tight i don't want to mess with them but i'm willing to do whatever it takes....

PITAPan wrote:
Put a washer on the petcock nipple ....

I even went back and looked first.

Still missed it.

A smear of silicone grease on the peacock nipples work fine

I always rebuild my calipers when changing pads on a bike that has had those pads in for more than two years. The seals are inexpensive and you prevent replacing more expensive parts down the line and your brakes work better. I like saving money.