the pulse of a brake

[DGXSER]

Pulsing brakes has been the most troubling thing for me on these special bikes. Had this issue on Thunderstruck, got them mostly cleared up, but always felt a little like a warped rotor.

Now, I have Banshee, and the brakes felt fine. Then I swapped wheels with Thunderstrucks since they had new rubber on them. I also made a point to swap out the rotors since I knew the ones on Thunderstruck always seemed a little pulsing to me.

Well, now I find I get the pulsing on Banshee!!! So, is it possible it is actually in the wheel and not the disc? Is there some super secret impossible to figure out method of putting the brakes together on these I am missing? Do they need to be lose so they can rotate as needed when braking?

I thought I had this all down and no problems, but this recent development makes me wonder at what point I went wrong here!!

[bikerphil]

DG, have you checked the runout on the wheels and rotors? Also, the caliper mounting bolts on the Special's front calipers can become slightly bent and may cause the feel of warped rotors. Maybe some debris between the rotor and wheel causing the rotor to appear warped? If you used any anti squeal goop on the back of the pads, did you clean all the old stuff off so the pads sit flush in the calipers? Just a few thoughts.

[79XS11F]

The wheels on these bikes are darn near indestructible but as suggested check them for run out. Same with the disc's but I would guess that the real issue may be a defective tire, perhaps a bad wheel bearing that reveals itself only under braking loads. As for the tire, next time your out with the bike and it is safe to do so, stand up on the pegs and look down over the bars at the tire and see if the tread is running true. Bent caliper bolts and hard spots on the brake shoes can also feel like a warped disc.
Rob

[DGXSER]

Thanks Guys, I'll check the runout. Like I stated, it is so wierd that wiht the other wheel with these disc on it, the brakes worked great. and now, with only the wheel being different, they pulse badly as you come to a stop. Its like your letting off the brake and back on it as the wheel comes round.

The only other thing I can think is if I do not have the right side fork lined up well with the center of the disc. But even that should not cause the pulsing I would not think anyway.

[XS1100_OEM4ME]

Bolts

Thanks Guys, I'll check the runout. Like I stated, it is so wierd that wiht the other wheel with these disc on it, the brakes worked great. and now, with only the wheel being different, they pulse badly as you come to a stop. Its like your letting off the brake and back on it as the wheel comes round.

The only other thing I can think is if I do not have the right side fork lined up well with the center of the disc. But even that should not cause the pulsing I would not think anyway.

It does sound like the bolts that holds the caliper on the forks, had the same problem on my 79 special and a fellow member pointed out the bolt out of true thing. Other then that, as you have pointed out, new wheel, same breaks, could be rotor not flush with wheel. Just asking, did you do a two stage "star" patten tightening when you installed the rotors?