A Couple Of Problems

JoeNTMY
JoeNTMY Posts: 8
edited January 2015 in MTB workshop & tech
I'm a bit of an amateur when it comes to maintenance and I've just tried to give my bike a bit of a service. In doing so, I've come across two problems that I'm unable to remedy. They are:

When I turn my handlebars there is a creaking/cracking noise.

When I went to change my brake pads I noticed that 3 of the 4 pistons are stuck in the caliper? (correct me if I'm wrong) when I press the breaks, meaning the front brake doesn't work at all and the back brake only half works. :( Is there anything I can do to get the pistons to pop out or even better, work?

Any advice would be greatly appreciated! Thanks

Comments

  • rockmonkeysc
    rockmonkeysc Posts: 14,774
    Your calipers need a service. Google for service kit and instructions for your model of brakes.
    Your headset bearings are probably dead, take the bearings out and take them to a bearing shop to get replacements.
    Transition Patrol - viewtopic.php?f=10017&t=13070235
  • The Rookie
    The Rookie Posts: 27,812
    Creaking when turning the bars could be anything from cable rub to a headset in need or replacement of just preloaded to much, does it feel tight to turn?

    It's brakes, not breaks, that's what happens when you have no brakes!

    How do you know they are seized? Not moving doesn't make them seized, it's rare for them to seize so they don't come out under pressure, they usually fail to retract first. What make and model of brake?
    Currently riding a Whyte T130C, X0 drivetrain, Magura Trail brakes converted to mixed wheel size (homebuilt wheels) with 140mm Fox 34 Rhythm and RP23 suspension. 12.2Kg.
  • JoeNTMY
    JoeNTMY Posts: 8
    Thanks for the responses.

    Hopefully I can service them myself. I wish I'd of started all this maintenance stuff 15 years ago!

    It doesn't feel tight to turn. Would balancing on the bike (with the handlebars almost at a right angle) damage the bearings?

    I've reset the pistons a few times with a piston press as the pads were rubbing on the disc. I don't know if they're seized, just presuming they are.

    They look like they're Tektro Gemini:

    DSC_0345.jpg

    Thanks
  • The Rookie
    The Rookie Posts: 27,812
    Rubbing doesn't make them seized, if the brakes work, just ride it and stop overthinking it!

    No balancing on the bike like that won't hurt the headset.
    Currently riding a Whyte T130C, X0 drivetrain, Magura Trail brakes converted to mixed wheel size (homebuilt wheels) with 140mm Fox 34 Rhythm and RP23 suspension. 12.2Kg.
  • JoeNTMY
    JoeNTMY Posts: 8
    The Rookie wrote:
    Rubbing doesn't make them seized, if the brakes work, just ride it and stop overthinking it!

    No balancing on the bike like that won't hurt the headset.

    The brakes don't work though. The front brakes are non existent - I've taken the wheel off, squeezed the brakes and the pistons don't move at all. The back brakes work, but very poorly - I've taken the wheel off, squeezed the brakes and only one piston moves.

    I was just trying to give some background info. on the situation. I thought maybe I'd pushed to pistons to far in when resetting them?

    Thanks. I'll have to get the bearings checked out on the headset then.
  • The Rookie
    The Rookie Posts: 27,812
    If you can move the lever and the pistons don't move then there isn't enough fluid to move them, the fluid is incompressible so you can't move the lever and not move the pistons if the system is full as it should be.

    Also with no resistance it's not unusual for only one piston to move, it only needs to move at a fraction lower pressure than the other and the second will never move unless you stop the first one!
    Currently riding a Whyte T130C, X0 drivetrain, Magura Trail brakes converted to mixed wheel size (homebuilt wheels) with 140mm Fox 34 Rhythm and RP23 suspension. 12.2Kg.
  • JoeNTMY
    JoeNTMY Posts: 8
    The Rookie wrote:
    If you can move the lever and the pistons don't move then there isn't enough fluid to move them, the fluid is incompressible so you can't move the lever and not move the pistons if the system is full as it should be.

    Also with no resistance it's not unusual for only one piston to move, it only needs to move at a fraction lower pressure than the other and the second will never move unless you stop the first one!

    Are you saying that I need to apply some brake fluid then? I've not used any since I've had the bike (18 months).

    Sorry for being a complete amateur. I really appreciate your feedback!
  • The Rookie
    The Rookie Posts: 27,812
    If the lever is moving and the pistons not, then you have air in the system, so you need to go through the fill/bleed process, you may also have to sort out the why (you have air in the system which shouldn't happen) as well.
    Currently riding a Whyte T130C, X0 drivetrain, Magura Trail brakes converted to mixed wheel size (homebuilt wheels) with 140mm Fox 34 Rhythm and RP23 suspension. 12.2Kg.
  • JoeNTMY
    JoeNTMY Posts: 8
    The Rookie wrote:
    If the lever is moving and the pistons not, then you have air in the system, so you need to go through the fill/bleed process, you may also have to sort out the why (you have air in the system which shouldn't happen) as well.

    Thanks a lot! I'll check this out.

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