Curing the annoying disc brake squeal
Almost everyone has experienced disc brake squeal at one time or another. What causes this? It's simply a high frequency vibration that creates a harmonic between the caliper body or piston and the back of one or more brake pads (just like vocal cords). It usually occurs often at lower speeds as the bike is slowing to a halt, very annoying and embarrassing when your high dollar hog squeals like a pig as you come to a stop at a busy intersection.
Several things can initiate the squeal. It can be caused by pads that have become glazed from extended braking, incorrect pad compound for the type of riding you do, or contamination of the surface, as from dirt, sand, or accumulated brake dust.
The surest cure is to perform a double fix on the pads themselves. First, camber the leading edges of the pads at a 45 degree Angle using a belt sander or bench grinder (see illustration). This helps the pad to glide along the rotor's surface more smoothly, sort of like the curves of a sled's rails. Second, use anti-squeal shims on the back of the pads. These usually come in the form of thing peel and stick aluminum sheets that you simply cut to fit the back of the pads. They work by actually absorbing the vibration and isolating the two harder metals from each other. Anti-squeal shims also come in other more exotic compounds (like rubber, Fiberglas, or Teflon), but I find the aluminum ones work best and cost the least. You can find them at most auto parts stores.
You may have seen or used a thick blue or red liquid anti-squeal compound that you apply to the backs of the pads. These products offer a temporary solution at best, and leave plenty of room for error (not to mention possibly fouling your pads). The can help if applied properly and allowed to cure thoroughly before reinstalling the pads, but I strongly recommend using the shim type products. While the pads are of, it never hurts to lightly sand the surface to remove any glazing, also a scuffing of the rotors with an abrasive pad or very fine sandpaper will help. And of course, always check pad wear and brake fluid level whenever you disassemble your brakes. Also be sure to grease the caliper mounting pins (if applicable on your model), as dry pins can actually contribute to brake squeal. And remember to test brakes before playing in traffic.
Let's not forget that HD came up with the service bulletin (M1192A)that swaps the two front rotors on touring bikes to eliminate the squeal also. Left to the right side and visa versa. See the link below.
Brake rotor swap
Also take a look here...
Rear Brake Noise 08-09 Touring - Harley Davidson Community
Also see these posts...
Replacing Rear Brake Pads (Softail) - Harley Davidson Communityhttp://www.hdtimeline.com/brakes_tires_and_wheels/936-brake_squeal.html
Reverse Brake Bleeding. - Harley Davidson Community
Almost everyone has experienced disc brake squeal at one time or another. What causes this? It's simply a high frequency vibration that creates a harmonic between the caliper body or piston and the back of one or more brake pads (just like vocal cords). It usually occurs often at lower speeds as the bike is slowing to a halt, very annoying and embarrassing when your high dollar hog squeals like a pig as you come to a stop at a busy intersection.
Several things can initiate the squeal. It can be caused by pads that have become glazed from extended braking, incorrect pad compound for the type of riding you do, or contamination of the surface, as from dirt, sand, or accumulated brake dust.
The surest cure is to perform a double fix on the pads themselves. First, camber the leading edges of the pads at a 45 degree Angle using a belt sander or bench grinder (see illustration). This helps the pad to glide along the rotor's surface more smoothly, sort of like the curves of a sled's rails. Second, use anti-squeal shims on the back of the pads. These usually come in the form of thing peel and stick aluminum sheets that you simply cut to fit the back of the pads. They work by actually absorbing the vibration and isolating the two harder metals from each other. Anti-squeal shims also come in other more exotic compounds (like rubber, Fiberglas, or Teflon), but I find the aluminum ones work best and cost the least. You can find them at most auto parts stores.
You may have seen or used a thick blue or red liquid anti-squeal compound that you apply to the backs of the pads. These products offer a temporary solution at best, and leave plenty of room for error (not to mention possibly fouling your pads). The can help if applied properly and allowed to cure thoroughly before reinstalling the pads, but I strongly recommend using the shim type products. While the pads are of, it never hurts to lightly sand the surface to remove any glazing, also a scuffing of the rotors with an abrasive pad or very fine sandpaper will help. And of course, always check pad wear and brake fluid level whenever you disassemble your brakes. Also be sure to grease the caliper mounting pins (if applicable on your model), as dry pins can actually contribute to brake squeal. And remember to test brakes before playing in traffic.
Let's not forget that HD came up with the service bulletin (M1192A)that swaps the two front rotors on touring bikes to eliminate the squeal also. Left to the right side and visa versa. See the link below.
Brake rotor swap
Also take a look here...
Rear Brake Noise 08-09 Touring - Harley Davidson Community
Also see these posts...
Replacing Rear Brake Pads (Softail) - Harley Davidson Communityhttp://www.hdtimeline.com/brakes_tires_and_wheels/936-brake_squeal.html
Reverse Brake Bleeding. - Harley Davidson Community
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