Bicycle Mechanics - Front brake caliper won't stay centered

On my new Cervelo Soloist. I'll adjust the little screw on the top of the caliper so it's perfectly centered (which always involves tightening), but after a ride, it'll be off again.

Is the screw working its way out? Is this a common problem? Is the best remedy a little bit of blue Loctite?

have you marked the screw to see if it is working it's way out?

have you marked the screw to see if it is working it's way out?

+1 do this.

Good idea. I'll put a little Sharpie mark on it the next time I go riding.

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Operator, this is driving me crazy--what do you mean by your signature? :) Is it something deeper than just the linear algebra definition of a span?

D

I hope linear algebra isn't needed to solve my caliper problem.

I doubt that little return spring tension screw is working it's way out. It's primary purpose, buy the way, isn't to center the arms. It's purpose is to equalize the return spring pressure so that the arms release simultaneously.

If it was my bike, the first thing that I'd do would be to disconnect the brake cable. Then I'd back out that spring tension screw about half way. Then I'd loosen the bolt that holds the whole caliper onto the frame and retighten it when the brake caliper arms were equi-distant from the rim. Reconnect the brake cable and finally do whatever fine tuning is necessary with the return spring screw.

Ah, good to know. Since the bike is new, and my time is short, perhaps I will just let the shop deal with it.

It's confirmed. The screw is definitely working its way out of the caliper. I started a ride with the screw more or less flush with the surface of the caliper. By the end of the ride, it had risen quite a bit above the surface of the caliper (and become grossly off-center). I'm going to reposition it and dab a little Loctite on it.

It's confirmed. The screw is definitely working its way out of the caliper. I started a ride with the screw more or less flush with the surface of the caliper. By the end of the ride, it had risen quite a bit above the surface of the caliper (and become grossly off-center). I'm going to reposition it and dab a little Loctite on it.

Loctite is anaerobic. Dabbing it on an adjusted fastener will do nothing. You must take the fastener completely out, apply loctite to the threads, then reinsert fastener.

Good point. Thanks.

Oh yeah, make sure you don't put permanent loctite on that either.

Nope, just the blue stuff.

Operator, this is driving me crazy--what do you mean by your signature? :) Is it something deeper than just the linear algebra definition of a span?

D

lol :) You are not the first person to say this.