Rebuilding calipers?

[northwind]

This thread confused the hell out of me... "Dar bought another TL! And Mike Numbers is back! And so's Bartyboy! And Randy and Donnie have returned from SVR! And I'm still 26! Wait..."

Anyway, since we're zombie-threading, I reuse seals most of the time since I never let my calipers get bad enough to destroy them, but I wouldn't do it on anyone else's bike, it's my decision/risk/responsibility, so I always use new seals on anyone else's calipers. I've bought a replacement rear caliper twice now, because they're so ridiculously cheap- £5 for a caliper with pads, cheaper than buying seals let alone pads. But that's always a gamble of course, I like to buy Busa calipers because they tend to see less manky roads than SVs.

Airline is the correct tool to remove pistons. But they come out rather fast, I once fired one the entire length of my garden... Then decided that next time I'd point it at the ground, and ended up having to dig a piston out of a surprisingly deep hole in the lawn. Bucket of water is good, makes a mess but stops the piston nice and gently, and deals with any fluid too. If you did this sufficiently stupidly, losing an eye would be very easy. And remember compressed air bites...

Originally Posted by northwind

Airline is the correct tool to remove pistons. But they come out rather fast

Or one of these...



This is allowed in the house...

surely buying new ones and then rebuilding the old ones so you have a spare set and time to work on them is the best road to go down. Even if your skint buying new ones and selling old ones to be rebuilt is gotta be worth a shot. Sounds like the best road for Ceri anyway.

[northwind]

Mmm, that'd depend. Personally I'd just take a closer look then make a call, servicing brakes doesn't take long if you're familiar with it and you have all the bits but if it turns out that you need a seal or (whisper it) new pistons then all of a sudden you have no bike for the duration.

[Sid Squid]

I've never seen a set of calipers so worn hydraulically as to need replacement, however I've seen several sets worn on the sliders such that the calipers are unusable.
If you do the work yourself, assuming you're able of course, then rebuilding is always cost effective as long as the above is bourne in mind.
If however you're paying a shop to fix them, then replacement might be best - after you've paid for parts and labour a new might not be dearer.

[yorkie_chris]

Also compressed air is not always enough. Unless you have better compressors than me? Have used up to 110psi and failed!

Perfect piston removing tool comes free with the bike.

[northwind]

I'm working on the assumption here they're already removed But yeah, if they're fitted it's daft not to just use the handy lever provided for pushing the pistons back and forth.

Originally Posted by Sid Squid

I've never seen a set of calipers so worn hydraulically as to need replacement, however I've seen several sets worn on the sliders such that the calipers are unusable.

Forgive my ignorance, but are the sliders the bits of the caliper that the pads slide forwards and backwards on? E.G. The male bit that goes through the holes on either end of the pad (well, 2 on one pad, 1 on the other).

[yorkie_chris]

Yup, and the bores can wear.

Originally Posted by yorkie_chris

Yup, and the bores can wear.

Ah, mine are still nice and snug. I think I'll go for a new set of seals and giving the pistons a really good clean and replace the brake hoses at the same time. I'll have a Haynes, large bottle of new brake fluid, a tub of that magic red castrol rubber grease (which doesn't harm the brake fluid), tub of copaslip, can of brake cleaner, wire brush and mityvac to hand, anything else I need to get or should be aware of before attempting it?

I've got a Dremmel-like thing with a load of attachements, will it be okay to use that to get in the nooks the wire brush can't reach to clean up parts, provided I thoroughly clean all the dislodged dust/carp off with brake cleaner afterwards?

Thanks for all the advice folks, it's v. much appreciated.