Not sure what I’ve done wrong. Had a scoot round the internet. Do I have to do something with the pistons and if so what are they?
Any help much appreciated!

Did you use a tyre lever or screw driver to push the pistons back in before taking the old pads out?

Have you pushed the pistons back into the calipers? If not you can use a screwdriver with a cloth, but this isnt recommended, preferably use the U shaped end of a spanner as this won’t hit the wee knobbly bit in the middle of the pistons.

As above (carefully) try to ease the pistons back.

NB: my rear piston seized recently and I shattered it when trying to (not so carefully) “ease them back”

probably best to then check that both pistons move freely – press lever with no pads in are both sides moving and equally?
If they were bled with the pistons not fully pushed in they may not go all the way back in. You can undo the bleed screw and if you get really lucky you wont need to bleed afterwards.

http://www.chainreactioncycles.com/Models.aspx?ModelID=3614
This or something similair is the best thing I’ve found for pushing pistons back in, without buying the proper tool obviously.

Thanks guys! Tried to push them back in but to no avail.
Junkyard, when I pull on the brake lever the right one (nearest the spokes) comes out but I can’t get it to go all the way back in. Have tried to move the screws around it too (allen key ones) but can’t move them.
I just noticed caliper is a bit oily now too. Might have to make a trip to my LBS.
Thanks a lot everyone anyway but I think this one’s beyond me 🙂

get a rebuild kit and a bleed kit, it is pretty easy.

My Avid 7s need a bloody good shove to get the pistons pushed back – may be worth refitting the old pads and really getting some weight on them. Just make sure you give it all a good clean up before the new pads go in.

I’ve run Juicy’s for years. For what folk sell them off for on here, they are excellent brakes, but they need a bit of fettling.

Turn the caliper upside down & bolt it to the opposite side of the mount – screw in from the rear. Just so you can work on it held firmly.
Open the tiny bleed screw on the lever a tiny bit.
Using two flat screwdrivers in a sort of scissor action push both pistons back at the same time. Close the bleed screw. They will go right back in. “Assemble” the pads & spring & locate them in the caliper. There is a correct way, the spring is offset, its easy to see. One at a time grip the little tabs with some pliers & click them into place. often they will push in with finger pressure.
Periodically, take out the pads & gently work the brake lever so the pistons come out a few mm, then give them a spray of GT85. Push them back in & repeat. Helps to stop them sticking.
Dont be tempted to run Juicy pads right down, they are more prone to sticking the more the pistons come out of the bores.