Bicycle Mechanics - disk brake calipers

Is it possible to knock the disk brake calipers out of alignment ?

I went off a curb yesterday and there was this weird grating sound for about 2-3 minutes afterwards and the brake lever for the front disk brake was suddenly squishy.

I am not sure what I did but then later, it's like it sort of sprung back and wasn't so unresponsive. I am not sure what is going on. Is this common ?

Justen

Weird stuff happens with disc brakes sometimes......go huck off of a curb again and see if the same thing happens. If the caliper got knocked out of alignment the lever wouldent get squishy.....I have no idea.

Hi Klein,

I am used to the "twanging" noise the the front 8" rotor makes from time to time - usually on tight turns and stuff but this was a completely different sound. It was horrible. I was sure I had done something pretty bad to it and this is after a tiny bump off a 12" curb.

The noise persisted, LOUDLY, for a few more feet and then stopped but the lever was not as tight. Weird !! I dropped in at a nearby bike shop and they told me that the caliper had been knocked out of alignment and it would be a 15 minute job to straighten it out again. This was not the store I bought it from so will go back to them today sometime and have them check it out.

Justen

if your lever got squishy you may have air in your line breed your brakes

Breed my brakes eh ?...hmmmm...maybe I'll get some baby Hayes ! yeah...I know. Bad joke but it's 7 AM ! What do you expect.
Seriously though, I have mechanical disk brakes. I thought it was only Hydro brakes that need to be bled.

Thanks for the suggestion though.

Justen

Mechs are touchy things. I had a wipe out the other day over some rocks, the rear caliper must have taken a shot. I jumped back on and the rear was locked up, wheel wouldnt even move. So it took a minute to totally adjust both the inner and outer pads!

sorry my mind reading skills are slow! You didnt say you had hydros/mechs but the real problem is your still running mechs. Its a little odd for mech disk brakes to all of a sudden get "mushy" unless your cables are loose

I have mechanical and they are driving me nuts. They seem to be dragging alot...
I am breaking in the rear rotor again as I had it replaced on the weekend - but I understand the break in period so no problem wtih that but the front one feels like it is constantly dragging and the lever has had to be tightened a number of times now because it just doesn't seem to grip and hold.

Justen

Cant say I have those problems, but I have about 700 miles on my cannondale and the mechs are a constant adjustment issue. Just when I get the pads set just right, take off either wheel, and the adjusting process starts all over again. It seems that my rear rotor is warped to, never did anything to cause that, but it makes the pad adjustment more difficult!

Nikos try this next time.
When reinstalling your wheels before you tighten the QR squeeze and hold (I use a velcro strap) the brake lever this serves to position the rotor in the calipers. I've been doing it this way for some time now and I don't have any of the adjustment woes that you seem to have nikos. This method also works on V-brakes as well.

Is it possible that I have knocked the calipers out of alignment somehow by going down the stairs ? It's quite a bit of jolting and bashing on the back wheel although I thought this kind of bike should be able to handle it.

Justen

Not having Hayes I can't really say for sure but it sure doesn't sound right. Perhaps the pads got jolted out of their proper position?

Hey, thanks for the tip - I will give that a try.

No prob nikos:D

If the calipers come out of alignment, then they are not tight enough. They are definately not supposed to move.