Forum menu
XTR Disc issue--any...
 

[Closed] XTR Disc issue--any suggestions?

Posts: 0
Free Member
Topic starter
 
[#1765740]

My rear disc brake developed a strange feel on a ride this morning. It started getting a "catch" feeling in the first 1/2" of lever movement and smooth after that----at the same time, the rear brake isn't engaging well---have to use more lever pressure than usual to get full braking. The pads are only a month old and only sightly worn--- there is even spacing on each side of the rotor and no dragging/rubbing.
Any thoughts? I can do most adjustments/repairs, but brakes, for some reason always seem difficult for me.


 
Posted : 03/07/2010 5:31 pm
Posts: 507
Free Member
 

Sounds like you may have a sticking caliper piston to me.


 
Posted : 03/07/2010 6:05 pm
Posts: 0
Free Member
Topic starter
 

I just took a close look and I think you are right about the sticking piston. One side of the caliper is closing and the other not. Any ideas on a way to loosen a sticking/stuck piston outside of replacing components?


 
Posted : 03/07/2010 7:59 pm
Posts: 0
Free Member
 

Hold the moving one in and use lever pressure to free up the other one - when it has moved out clean it and lube it - mineral oil for shimanos - and then work it in and out a few times

Of course it must be a figment of your imagination - nothing goes wrong with shimanos -everyone knows that.

Good luck attempting to get spares for it - not many bits are available


 
Posted : 03/07/2010 8:02 pm
Posts: 0
Free Member
Topic starter
 

Hey Tandem, thanks, that did the trick and freed up the stuck caliper. I am assuming it was just fine dust that had it gummed up. Riding here in the SW US, dust & sand is the biggest culprit--we don't have to worry much about wet conditions.


 
Posted : 03/07/2010 9:14 pm
Posts: 0
Free Member
 

I use copper grease to help lube the brake caliper pistons. Works for me anyway ๐Ÿ™‚

Edit: Oh and also a spray can of switch cleaner is a good solvent to clean brake stuff up and remove any small amounts of stray brake fliud, oil, grease or thumbprints


 
Posted : 03/07/2010 10:59 pm
Posts: 0
Free Member
 

Check the rivets that hold the disk to the spider for play.
I've had 4 disks work loose so far!

to rectify get a hammer and ............... re-rivet!


 
Posted : 04/07/2010 2:20 pm
Posts: 0
Free Member
 

Nainosliw - Member

I use copper grease to help lube the brake caliper pistons. Works for me anyway

I would never use it in this way - use something you know is specifically designed and safe to do so. Copaslip is gritty

Edit: Oh and also a spray can of switch cleaner is a good solvent to clean brake stuff up and remove any small amounts of stray brake fliud, oil, grease or thumbprints

Again - be very careful - some switch cleaner contains lubricants and I don't know what the solcvents will do to the seals.


 
Posted : 04/07/2010 2:32 pm