Avid mech pad-adjust dial not turning.

[ToNYC]

Fellas, I posted this on MTBR also. I was fiddling w/ my brakes, making adjustments, turning the larger red dial to loosen the pad then when I tried to turn it back the other way, it won't turn anymore - it's STUCK! Anybody else had this problem b4? 'will appreciate any input.....

[jimbo]

Did you try taking the pads out to see if there is any crap in the caliper housing?  Might be something stuck in there.  

I noticed the new Avids with the spring pad clip could be a problem if you accidently bend the spring trying to mount the wheel also.

[keen]

  You can pop the dial off and try and move the piston adjuster tab w/ a pair of pliers. My used avids required a dab of grease on the inside of the red dials to keep them moving freely.

[GET]

I have not had this happen to my Avids yet, but have had the inner caliper pistons on my Hayes mechanicals seize.  The problem there is that the caliper housing is cast aluminum and the threaded piston is also aluminum.  This is an absolute no-no in aerospace engineering.  They will seize/gall eventually.  I suspect the Avids have a similar material choice for weight/cost savings.  I suggest everyone lubricate these threads with a high quality anti-seize compound or brake grease and turn them in and out a few threads once in awhile, even if they don't need adjusting.  If the lubricant has been "washed out" and the piston is turned, or just sits in one place for a long time, galling/seizing is likely.

Oddly enough, the older Hayes has a steel piston.  Magura also uses steel in its brakes with manually adjustable inner calipers.