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  1. #1
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    Squeezed with no wheel on.....

    Hey guys,

    Rookie question, I know, but I squeezed my brake lever on my front brake without the wheel on by accident and now my pads are rubbing all the time. Do I need to bleed the brakes or is there a simple way to fix this.

    Thanks in advance.

  2. #2
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    Quote Originally Posted by cjdavis
    Hey guys,

    Rookie question, I know, but I squeezed my brake lever on my front brake without the wheel on by accident and now my pads are rubbing all the time. Do I need to bleed the brakes or is there a simple way to fix this.

    Thanks in advance.
    Whoops!

    Best way to fix it is to pull the pads compress the pistons back in the caliper, re-install pads and pump the brakes a few time (with the wheel on) to reset the pad position. best implement to push pistons back in would be a plastic tire lever.

  3. #3
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    not an issue, easy fix.
    Why would I care about 150g of bike weight, I just ate 400g of cookies while reading this?

  4. #4
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    If you have pistons with a little post in the center to help retain the pads (Hayes, Avid?), you should use a 10mm box spanner to push them back in. Whatever you don't apply pressure to the pad post as it could quite easily snap off.

    You don't necessarily need to remove the pads, either. Taking care not to damage the pads, or using a small piece of folded card to cover them, use a large flathead screwdriver to gently lever the pistons apart. However...

    If the brake has been in use for a while there may be a build-up of brake dust and/or dirt on what were the exposed areas of the piston walls. If you push the pads/pistons all the way back into the caliper without removing this build-up, you're going to force some of it back into the piston seals, which could lead to the pistons not being able to retract properly or to one piston moving out at a different speed to the other. It's a judgement call depending on the condition of the brake, but it's easy to clean the pistons/caliper interior with a blast of silicone spray or a few drops of brake fluid (DOT or mineral, depending on what your brake uses) a cotton tip and some tissue to wipe up the excess fluid.
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  5. #5
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    Is it an issue if it sounds like there is air in the brake line near the lever. I can hear it when I apply the brakes quickly... Or will this fix itself when I reposition the pistons?

    Thanks

  6. #6
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    It's highly unlikely that you got air into the system by extending the pistons with the rotor out, particularly as the pads were still in. That's not to say that there's no air in the system, just that it would be very unusual to introduce it by doing what you did.

    You're also unlikely to hear air in the system. You may hear rubber seals moving, but if you had enough air the system to make a squishing noise then you would almost certainly have obvious symptoms in relation to brake performance and/or feel.

    Just get the pistons/pads apart again; you can probably do it just by pushing/pulling the rotor against the pads (bearing in mind what I said earlier about getting dirt in there). If you're left with a soft/squishy feeling lever once the pads are balanced again, then you can think about needing to get the brake bled.

    By the way, what brakes are you using?
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    What luck for rulers, that men do not think - Adolf Hitler

  7. #7
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    Leave the pads in and use a tyre lever to prise them apart.
    Brake pads are a wear part and pretty hard to damage. Pistons however are very easy to chip and mess up.
    Owner of www.shockcraft.co.nz and NZ Manitou Service Agent.
    www.dougal.co.nz Suspension setup & tuning.
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  8. #8
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    If there is still a gap, I have found a cheap butter knife handle seems to be JUST about the right width to spread pads apart. Most of the time, the blade part has a nice taper to the handle part, so you just press it in and you're all set (with the pads in).

  9. #9
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    It kills me when people recomend to newer riders to pull the pads and reseat the pistons.
    It is so much safer to just pry against the pads. Worst case is you dent the pads a bit. Your brakes will still work.

    the pistons are phenolic or other type of brittle composite material. VERY easy to damage. especially if they have the post in the middle.
    A large flat head screwdriver, clean of course along with some gentle SLOW twisting between the pads is all that is usually needed.

    Steve UK has it right about the dust buildup, and went into good detail as usual......= )

    But I see alot of people recomending to pry the bare pistons apart which IMO is a no no unless you have wrench experience and know what you are doing.

    Sorry for *****ing, maybe I haven't had enough coffee yet......= )

    BTW, even a plastic lever can chip the edge of the piston.
    Look, whatever happens, don't fight the mountain.

  10. #10
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    Quote Originally Posted by ettore
    If there is still a gap, I have found a cheap butter knife handle seems to be JUST about the right width to spread pads apart. Most of the time, the blade part has a nice taper to the handle part, so you just press it in and you're all set (with the pads in).
    I was going to suggest the trusty butter knife as well Wide, flat, and slightly wedge-shaped. I'm surprised Park does not sell one for $15.
    15mm is a second-best solution to a problem that was already solved.

  11. #11
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    Quote Originally Posted by kapusta
    I was going to suggest the trusty butter knife as well Wide, flat, and slightly wedge-shaped. I'm surprised Park does not sell one for $15.
    They do, and it's actually one of my favorite tools!!!!!!
    http://www.parktool.com/products/det...t=14&item=PP-1
    Look, whatever happens, don't fight the mountain.

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