Are these hydraulic calipers serviceable?

[andyoxon]

Do these hydraulic calipers look serviceable with a bit of work, and what type do you reckon they are - flat mount with post mount adaptors?  Just wondering whether to source new ones or attempt to salvage?

brake1 by a oxon, on Flickr

brake2 by a oxon, on Flickr

brake3 by a oxon, on Flickr

[Hot Flatus]

They are serviceable if not leaking. I have some of those, they've lasted 9 years so far in all weathers. Give the pistons a wipe with alcohol. When reconnected (ask later about which inserts to use  ) push the pistons out 5mm and clean with alcohol. Let dry, then lube with mineral oil. Then push pistons back in with plastic tyre lever.

I'd recommend a full bleed.

They are post mount. Adaptors easily available for any eventuality)

[andyoxon]

Thx.

Had a closer look now. 

On one caliper the pistons don't move at all - pistons fully in, & on the other caliper, slight movements in both - one piston mostly out, the other mostly in.  Cleaned with isoprop, though h-fluid leaked from piston (one mostly out) - poss because I 'rocked' it with the toothbrush. 

Guessing the shimano piston seals aren't supposed to be replaceable?  Even with a ton of fiddling, perhaps the piston movements may not be at all even or leak free - not sure, no experience with hydraulics. 

OOI whats a usual/good value bleed kit for Shimano 105 levers?   

edit.  Worth having a go at these or just pick up new?

[Paul H]

Those calipers are probably salvageable, but when replacements cost £12.50, including new pads, you have to weigh up if it's worth the effort.
https://www.bikeparts.co.uk/products/shimano-altus-br-mt200-front-or-rear-disc-brake-caliper-post-mount-black

I use Epic bleed kits, though having always done so I can't compare with anything else.
https://epicbleedsolutions.com/

[Hot Flatus]

I'm not sure it's worth the hassle repairing them if non-functioning because if the repair doesn't work you'd have put in several hours work for nothing plus cost of parts

[andyoxon]

Thanks both.

Never used bikeparts.co.uk -  interesting, will have a look.

[andyoxon]

Are ceramic pistons worth the extra over resin caliper pistons?  Longevity?

[FifeingEejit]

Looks like a Post Mount - IS mount adapter.

I've destroyed more ceramic pistons than resin.

[DuncanM]

The pitch is that the ceramic pistons are stiffer and stay rounder for longer, so leak less. The thing is that if crap gets in then they can also break. I had a set of the 505 calipers where the piston broke up inside the caliper, so when I tried to push them back to fit new pads I damaged the caliper. They were relatively old by that point, and they didn't leak though!

I used the Epic Bleed Solutions kit as well - I might still have it if you want to borrow it.

[Hot Flatus]

you can get cheap bleed kits on eBay for less than £10. Pretty much the same as Epic bleed tbh

[FifeingEejit]

that epic bleed kit for shimano road looks no different from what I use, cobbled together from the various shimano bits (I got with a brake set once) and the syringe from the epic system I bought for my MTB XT levers and promptly discovered that the seals don't like the pressure bleeding epic advocate.
Since then I've only ever put the syringe on the caliper end and used it to either pull fluid from or push it into the funnel at the top. (Shimano's plastic bag system is never enough)

[Lightning Phil]

You just need some syringes and tubing for the bleeding. The tubing you can buy separate cheap as chips.