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RedDawn
10-10-2010, 03:23 PM
Squeezed the brake levers on my bike when the tire was off. Now the pads are touching and i don't know what to do to reopen hem so I can get my tire back on. How do I open them again? What's this opening procedure called so I know what to google in the future?
Lagerstatten.ca
10-10-2010, 04:21 PM
Flathead screw driver is your only way to get them to pry apart. Next time just jam some paper or cardboard when you take off your tires. Most bike stores have some of those plastic pieces that fit in between the brake pads - if you ask nicely they'll give you some :)
Supa Dexta
10-10-2010, 05:08 PM
Yeah pry em apart. May need to bleed them though.
RedDawn
10-10-2010, 05:23 PM
Originally posted by Lagerstatten.ca
Flathead screw driver is your only way to get them to pry apart. Next time just jam some paper or cardboard when you take off your tires. Most bike stores have some of those plastic pieces that fit in between the brake pads - if you ask nicely they'll give you some :)

Is there a risk of damaging the pads if I pry it with a screwdriver?
Renagades
10-10-2010, 05:53 PM
Originally posted by RedDawn


Is there a risk of damaging the pads if I pry it with a screwdriver?

Yes but the other option sucks
revelations
10-10-2010, 06:53 PM
You will have to open the bleed port on the caliper to push them back properly, but a screwdriver might work as well.
Canmorite
10-10-2010, 08:04 PM
Probably need to have them bled. Stick cardboard in between them when the wheels are off next time...
superflychief
10-10-2010, 08:20 PM
ummm why the hell would you need to bleed them. there is no new air in the system. Just push them back with a screwdriver being careful not to damage it and remember to not do it again.
xinirgi
10-10-2010, 08:36 PM
The air would come from maxing out the piston travel on the calipers. It's not guaranteed that you'll need to bleed, but once you get your tire back on you'll know pretty much instantly.
sr20s14zenki
10-10-2010, 08:51 PM
Can you fit a c-clamp in there? leave the pad facing the piston on there, and c-clamp it back in.
Q-TIP
10-10-2010, 09:01 PM
Bicycle or motorcycle? Either way it is unlikely you will need to bleed them unless your pads were really worn. What brand of brake is it if it is a bicycle?
RedDawn
10-10-2010, 09:56 PM
^ it's a mountain bike shimano deor xt
EM1FTW
10-11-2010, 02:40 AM
stick playing cards in one by one until it expands enough to get the caliper around the rotor
Supa Dexta
10-11-2010, 05:03 AM
Playing cards? Do half the people in here even have a mountain bike/ with decent named disc brakes?

And the reason they may need to be bled is if the pistons have over extended, either using all the fluid in the reservoir, or even allowing air to seep past the seal.
Q-TIP
10-11-2010, 07:10 AM
To prevent damage to the pads first remove them, then GENTLY press with a large flat blade screwdriver on the pistons themselves. Once they are retracted into the caliper reinsert the pads and install the wheel. The first few lever pulls will pump up the system again. If the lever feels mushy after the first few pumps then you likely need to bleed the brakes. Thankfully I've never had an issue bleeding the Shimano XT brakes before and you probably won't have much trouble either. Just be glad you don't have Avids, those things are a PITA to bleed.

Just remember that because you have 4-pot brakes this process might be simpler with the pads in place. If you do damage them they are cheap to replace.
Graham_A_M
10-11-2010, 09:24 PM
Originally posted by Canmorite
Stick cardboard in between them when the wheels are off next time...

That would have to be some cardboard. :confused: I'd recommend a piece of metal, perhaps 1/8" steel or aluminum. Anything with less strength then even wood or playing cards would just crush. Those pads have a lot of clamping force.