What do you use for...
 

[Closed] What do you use for resetting your brake pistons?

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I changed the pads on my RX's last weekend and there's not enough space for the rotor with the new pads in.

So I put the old pads back in and got my big (8mm) screwdriver out and gave it a twist - nothing happened.

Do I need a wider bladed screwdriver? I though about using a chisel but it is too thick, do you have any tips that will help?

Thanks 🙂


 
Posted : 13/06/2013 10:40 am
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I use the proper park tool and it does the job every time without fail.

Dan


 
Posted : 13/06/2013 10:42 am
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Are these OEM pads? There have been lots of issues with non-genuine Formula pads simply being too thick to fit. Some folk have taken to sanding them down a bit first.


 
Posted : 13/06/2013 10:42 am
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I pop the piston back with the old pads & screwdriver.


 
Posted : 13/06/2013 10:43 am
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i use a pad spreader tool - it always works - unless its avids which i usually find by the time the owner brings them to me have already siezed solid.


 
Posted : 13/06/2013 10:45 am
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couple dinner knives jammed inbetween the pads.


 
Posted : 13/06/2013 10:53 am
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seosamh77 - Member
couple dinner knives jammed inbetween the pads
Ah, a fellow Avid user ?


 
Posted : 13/06/2013 10:55 am
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wooden clothes peg - ditch the spring and you've two opposing wedges to work with.


 
Posted : 13/06/2013 10:56 am
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I usually use the brake blocks and sometimes use a rubber mallet to hammer them in to push the pistons back in if I can't get the block in by hand. Works sometimes but other times I need to then bleed the brake. One tip I was given to stop the pistons sticking was to get them out a bit then rub some brake fluid on them with a cotton bud. I run avids and they get stuck all the time 🙁


 
Posted : 13/06/2013 10:57 am
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scaredypants - Member
seosamh77 - Member
couple dinner knives jammed inbetween the pads
Ah, a fellow Avid user ?
haha, used to be, no longer gladly!


 
Posted : 13/06/2013 11:01 am
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Screwdriver.


 
Posted : 13/06/2013 11:01 am
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Steel coaster


 
Posted : 13/06/2013 11:01 am
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[img] [/img]

£10 well spent.


 
Posted : 13/06/2013 11:02 am
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Big old screwdriver wedged against the old pads,never failed yet.....

Never had a problem with avids sticking,but then I aint one for cleaning my bikes much either.All those bike cleaning detergents remove far more than just the dirt.....


 
Posted : 13/06/2013 11:08 am
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thin tyre lever


 
Posted : 13/06/2013 11:10 am
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"The Force" 🙂


 
Posted : 13/06/2013 11:34 am
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Tyre lever here,

Although my Specialize multi tool has a handy little wedge which is good too


 
Posted : 13/06/2013 11:41 am
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The pads are from Discobrakes, it does seem you get quote a lot on there.

Should I fire up the belt sander to take a few mm off?


 
Posted : 13/06/2013 11:41 am
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I remove the pads and clean as much of the piston area as I can get to with some ISP, before replacing the old pads and levering with what I refer to as a FO screwdriver.

That generally works.


 
Posted : 13/06/2013 11:43 am
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Trowel.


 
Posted : 13/06/2013 11:46 am
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OP... From the sounds of your post the pistons are not fully retracted?

If they're fully retracted flush with the caliper body and you still cant get the disc between the new pads then clearly it's a thick pad issue.

If the pistons are not fully retracted then sanding off friction material you've paid good money for to make up for it is just daft.

If you're applying pressure with your screwdriver and the pistons wont go back as far as theyre supposed to then there's probably too much fluid in the system. Bleed the brakes with the pistons pushed fully back and restrained there.


 
Posted : 13/06/2013 12:06 pm
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I have a big old fat screwdriver which is ideal- it's absolutely useless for screws but deadly at opening tins and pushing back pistons (with the old pads still in, obv)


 
Posted : 13/06/2013 12:10 pm
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Plastic tyre lever.


 
Posted : 13/06/2013 12:20 pm
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I've just changed the pads on my Rx brakes... leave the old pads in situ, and lever apart with the widest flat screw driver you have. There's quuite a gap you need to make before you can easily insert fresh (superstar in my case) pads with enough clearance for the rota as well.


 
Posted : 13/06/2013 12:26 pm
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Shimano Deores and old XT. Pads out, very big flathead screwdriver - push pistons back into calliper, new pads in, squeeze lever 4/5 times.

Ride bike.

Be gentle if pistons are ceramic.


 
Posted : 13/06/2013 12:41 pm
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One of these

[img] ?width=800[/img]


 
Posted : 13/06/2013 12:46 pm
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I just use the Force. Jedi rather than constabulary, obviously.

Joking. Big screwdriver between the old pads has never yet failed.


 
Posted : 13/06/2013 1:39 pm
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I find that with avids if the dont return I just let a teeny bit of fluid out. All good. Havent bled em for ages...


 
Posted : 13/06/2013 1:43 pm
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i didnt know they did specific tools for this 😳

but i think i need one in my life instead of gouging at the piston/caliper with a screwdriver!

which is the best one to go for?


 
Posted : 13/06/2013 1:44 pm
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If the pistons are moving freely on my hope M4's and my X2's then they can be squeezed back in with just a finger and thumb one at a time. otherwise its an back end of old tire lever.
My juicy 7's need a set of old pads and big screwdriver.

Andy


 
Posted : 13/06/2013 1:51 pm
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I'll try cleaning them first with as the pad was very worn and it's been ridden through Epping filth all winter. So it's just the return as they were braking fine.

Then I'll try again.

@ Tracy, where can I got one of those Pedros levers from? I've done a search and nothing's come up.


 
Posted : 13/06/2013 2:33 pm
 lump
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@ Tracy, where can I got one of those Pedros levers from? I've done a search and nothing's come up.

http://www.chainreactioncycles.com/Models.aspx?ModelID=10021&_$ja=kw:%2bPedros%20%2bDownhill%20%2bLever|cgn:Pedros-XX-XX-XX-ModelID%3d10021+-


 
Posted : 13/06/2013 3:04 pm
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Thick screwdriver or a mini g-cramp if theyre being stubborn (old juicy 5s!)


 
Posted : 13/06/2013 3:12 pm
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cone spanner.


 
Posted : 13/06/2013 3:18 pm
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Park Tool blue placcy tyre levers, the thin ens, not the wide boys. I find the weird curved end bit fits nicely into the recess of the piston, rage the pads out, you'll muller them if you use anything ont eh pad.

Or, leave the pads in and press on the back of the pad to push in the opposite side piston


 
Posted : 19/06/2013 12:57 pm