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seized brake calliper

5460 Views 18 Replies 7 Participants Last post by  banana.logic, 
M
I got myself some new. Ferodo brake pads went to put them on and found out I couldn't move the piston to make enough room, thinking I can outsmart this I put it in the vice to try and push the piston back in. After cleaning it up with degreaser. It moved a bit but not enough before rthe vice handle started bending. Its not a very big vice but I did have a pipe on the end of the handle for more leverage. I then took it off tried again but still needed more room, so back in the vice it went but this time I snapped the corner of the bench off. (Its a chip board bench but still pretty thick). Any ideas on unsticking my stuck piston or do I need a new calliper. Eagerly awating responses cause sooo keen for a ride :p
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S
Push the piston right out of the caliper and clean it up. There are probably years of brake dust and other crud on the end of your piston and the seals obviously don't like it very much. I would have thought you'd root your seals before you bent your vise or broke the bench, but stranger things have happened before.

If you have knackered your seals, they'll be easy to replace once the piston is out.

A quick read of the manual will tell you everything you need to know and more. If the links haven't been ported over yet they'll still be stickied on the old forum. Good luck!
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B
seals are about 25 dollars per caliper from honda if I remember correctly. it is not an amazingly difficult process replacing them and cleaning up the pistons, but as always only do it if you are confident you wont mess it up.

There was a guide on how to do it on the old forum, I'm not sure if it has been brought across yet though.
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G
What happens when you try and force the piston back it often goes back in not square and binds up that's why you couldn't force it back.

All I use is a small G clamp and when I gets difficult I release the clamp, press the brake (this squares the piston up again) and then apply clamp again.

Like others have said. Build up or brake dust and rust can also stop it going back.

I use some scotch brite pad and clean the piston up as much as I can. Then some rubber grease helps it all go back in smoothly.

Please be careful what you use as some degreaser will actually swell up the rubbers.

Finally if your not sure, get some help.
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S
you will most likely need new seals after using degreaser on them... anything to do with brakes dislikes prettymuch anything other than brake fluid, water, brake cleaner or metho. dont use petrolium based fluids of anysort on brake components
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D
Are the Honda calipers usually hard to push in? (as in unable to do with hands)
My new Brembo's were so easy compared to the Nissin's and I could do it with one finger.
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S
^new being the main word there... they dont have any corrosion or gunge built up
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G
I have rebuild a few CBR calipers and with new seals they push in with one finger too. Like smiley said, new is the word.

Also you can get a grease called rubber grease (not K Y Jelly ya freaks) for lubricating brake seals and o-rings. I also use this to lubricate the rubber boots when installing carbies back on the bikes.
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N
studricho said:
I have rebuild a few CBR calipers and with new seals they push in with one finger too. Like smiley said, new is the word.

Also you can get a grease called rubber grease (not K Y Jelly ya freaks) for lubricating brake seals and o-rings. I also use this to lubricate the rubber boots when installing carbies back on the bikes.
Click to expand...
where'd you find your rubber grease stud?
I was looking for ages and then finally just gave up.
The other alternative would be to use brake fluid to lube your pistons up and push them back down like that. Worked a treat for me.
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studricho said:
not K Y Jelly ya freaks
Click to expand...
K Y is an excellent lubricant... it adds to the sensation of the..... brakes... and gets you places you might not be able to reach under normal... erm... braking conditions :nod:
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M
so rub up the piston with scotch brite and use brake fluid to lubricate as i dont got rubber grease. but how would i get the piston back out to do that?????:huh:
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S
connect brake lines, pump lever untill piston pops out. if a 2piston caliper, pump the first one almost out, clamp it, pop 2nd out, then remove 1st
and if you dont have brake fluid/rubber grease/ky jelly, you can use vegetable oil as a last resort
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L
Ninexz said:
studricho said:
I have rebuild a few CBR calipers and with new seals they push in with one finger too. Like smiley said, new is the word.

Also you can get a grease called rubber grease (not K Y Jelly ya freaks) for lubricating brake seals and o-rings. I also use this to lubricate the rubber boots when installing carbies back on the bikes.
Click to expand...
where'd you find your rubber grease stud?
I was looking for ages and then finally just gave up.
The other alternative would be to use brake fluid to lube your pistons up and push them back down like that. Worked a treat for me.
Click to expand...

Any Repco or Bursons will have it. If not they can definitely order it in for you.[hr]
And if you going to put new pads in, do yourself a favour and strip, clean and rebuild the caliper.

Get rid of that shit old fluid!

Your brakes will have more feel, operate smoother and stop quicker in an emergency.
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N
^^
did the rebuild about a month ago, swapped the pads over, completely drained the brake fluid, repainted my calipers, and im just putting everything back together now :)
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M
Got the piston out now gonna try find a new piston as i been told mine has got a dent an gonna get a new seal kit
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D
mr epic said:
Got the piston out now gonna try find a new piston as i been told mine has got a dent an gonna get a new seal kit
Click to expand...
Not sure if these fit, I was going to put these in until i got my brembo calipers

http://cgi.ebay.com.au/ws/eBayISAPI.dll?ViewItem&item=360188923379&ssPageName=STRK:MEWAX:IT
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M
Any 1 no if. The piston fom above will fit. Bit sketchy bout it being from ebay
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D
Ask the seller for the dimensions and cross check with the ones from you current set and also check service manual, these are cheap I reckon so it might be worth a go.
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B
ask the seller if they are genuine or aftermarket. pretty sure the calipers were the same on the mc19 and mc22...
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