I think this has cropped up on the forum before but might have been some time ago so may be some fresh data on this.

I have above Avid units and realised the rear had a lot less bite than the front. They've not had a huge amount of wear so was not expecting to have to replace pads or anything yet. When I dropped the pads out one side had a little, even wear but the other pad was down to nothing on one edge (so the pad was like a wedge – front to back). After some further tinkering I realised that the pistons were not coming out of the caliper evenly.

I found some advice on't net that suggested locking the "good" piston and pumping the brake lever to free the "bad" psiton. I tried this yesterday with zip ties and it seemed to work fine; with them on the "bad" piston seemed to be coming out perfectly well. However as soon as I drop the whole unit with new pads back on the bike it just reverts back to before; uneven presure and very little bite.

So, do I need to strip the whole caliper and re-furb it? If so what do I need? CRC have bleed kits but are they universal for all the Avid range? Do I also need new seals (?) internally in the caliper? Can you guess I've never done anything like this before? Anyone want to do it for me 😆

I have heard of this happening to people before but others who have had no trouble whatsoever with their Avid kit, so it must be fixable?

I've had this with juicys and elixirs – a proper pain…

On mine, the piston that comes out causes constant rubbing on the rotor – which increases the temperature in the system, exacerbating the problem.

I'm working on a fix – it seems to be working, but I can't convince myself that the problem is fully cured…

Pads out, push pistons in with a large flat head screwdrive (large to get some leverage on the piston). Hold the "free" piston in with the screwdriver and pump the sticky piston out of the bore (as far as you dare without wanting to pop it out and loose fluid – I find about 2mm is as far as I go.

Clean off all the manky brake dust and debris from the piston with a thin strip of clean rag or tissue, lube all round the exposed piston with plumbers silicone grease and push back in. Repeat for both pistons until both work smoothly.

What I seemed to find on the internet when I had the same problem was that the seals on Avids are square edged so as the piston moves the seal roles but can only move a certain distance. Basically the piston does not self align as the pad wears. What I did was take the pads out and then pump the lever just enough to push the pistons into the position you want, basically as close the disc as possible with just enough space for the pads. Then insert the pads and power should be back. Its a bit trial and error but does work.

Thanks guys. I'll have another fiddle with this when I get a chance.

I'm being urged not to just throw money at it and replace the whole system but it may come to this…

Throw in bin!! Avids are a pain, i went to xt and never had any problems since.

rkk01 is on the ball with this one.

I use a similar method to sort out my juicy brakes. I push one piston out as far as it will go (not to worried about it going past the seal and air getting in) put some silicon grease on a cotton bud and smear it round the piston then push back in and repeat for the other side.

I then bleed the brakes encase any air has got in during the fix or during use if the piston has been sticky.

On one set this did not help so I had to strip the calliper down and replace the pistons and seals (kit for juicies was less then a tenner so i guess elixirs will be about the same price) however when I did this I found a swarf of metal in the o-ring groove which must have been remnance of manufacture, once removed problem was sorted.

Bleed kit wise i am fairly confident the Avid bleed kit fits all avid brakes.

good luck with the quick fix. It may take a couple of smears of grease to get the full effect.

silicon grease on a cotton bud and smear it round the piston

Tried cotton buds at first, but found the ends a bit bulky – have now moved on to the thin flat ends of small zip ties… works like a small spatula to smear the grease around the piston.

Did one bike at the weekend, much improved, but could do with a second run through. Juicy 3s on wife's bike also need the same TLC before big ride this coming w/e

In the bin and get something that is either less of a rip off or something that is economically repairable.

"Economically repairable" rules out shimano then……..
Their spares are either the lever or the caliper, thats it.