Avid BB5 Brakes

logie48
logie48 Posts: 30
edited October 2012 in MTB workshop & tech
Hi.

I've got a boardman CX team, which is just new. But since my first ride i've now got a squeaky rear brake which is present even when not pressing the brake lever. It's that annoying that I refuse to ride it till it's fixed.

Now I know they haven't been bedded in properly, but I need to get rid of the noise to actually get the miles in to bed them.

So I took a look and realised that the moving pad do not sit straight/parallel to the other pad. Is this normal? I can also move the pad to a different angle by simply touching the spring clip.

Any suggestions?

Comments

  • nicklouse
    nicklouse Posts: 50,675
    go ride the bike.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • oxocube1
    oxocube1 Posts: 651
    Lightly sand the pads with fine sand paper and clean them and the disc with disc brake cleaner.
    Then get out and bed the pads in, if they are still noisy try the following:
    - Take the pads out and check for any damage/bend in the spring clip and the pads themselves.
    - Reset and align the caliper.
    - If neither of those work, try a different set of pads, new cable etc. to diagnose the problem.
  • cooldad
    cooldad Posts: 32,599
    Ignore this if it is that new and ride the thing^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    I don't do smileys.

    There is no secret ingredient - Kung Fu Panda

    London Calling on Facebook

    Parktools
  • chez_m356
    chez_m356 Posts: 1,893
    if its squealing when not braking it probably wasn't set up right, just re align it and/or check that the inboard "non moving" pad hasn't been wound in "towards disk" too far, this vid may give you some idea http://www.youtube.com/watch?v=H5zjUaTAQmY
    Specialized Hardrock Sport Disc 10- CANYON Nerve AM 6 2011
  • logie48 wrote:
    Hi.

    I've got a boarman CX team, which is just new. But since my first ride i've now got a squeaky rear brake which is present even when not pressing the brake lever. It's that annoying that I refuse to ride it till it's fixed.

    Now I know they haven't been bedded in properly, but I need to get rid of the noise to actually get the miles in to bed them.

    So I took a look and realised that the moving pad do not sit straight/parallel to the other pad. Is this normal? I can also move the pad to a different angle by simply touching the spring clip.

    Any suggestions?

    If its new as you say I would first take it back to where you got it from for them to have a look at. They should be able to sort you out. Though sadly Halfords are not exactly round for there customer service. If Halfords do refuse you have two options. Ask for a full refund and tell them to come pick the bike back up. Or if you like the bike take it to your local reputable bike shop and get them to have a look. If there is a problem they will be able to sort it for you. Then take a copy of the bill and post it to the Halfords you got the bike from and also a copy to the head office along with a very long letter of complaint asking for them to refund you the cost of the repair. I would also send a copy of your story to watchdog and trading standards.
  • logie48
    logie48 Posts: 30
    Thanks for the replies guys.

    The issue i'm having is that the outer brake pad does not sit straight when the lever is not pressed. It sits at an angle.

    I've adjusted them so that the rotor has minimal rub on the pads (I can't get them not to rub - again not bedded in yet).

    Now they are spongy, which is another pain in the ass.
  • cooldad
    cooldad Posts: 32,599
    logie48 wrote:
    Hi.

    I've got a boarman CX team, which is just new. But since my first ride i've now got a squeaky rear brake which is present even when not pressing the brake lever. It's that annoying that I refuse to ride it till it's fixed.

    Now I know they haven't been bedded in properly, but I need to get rid of the noise to actually get the miles in to bed them.

    So I took a look and realised that the moving pad do not sit straight/parallel to the other pad. Is this normal? I can also move the pad to a different angle by simply touching the spring clip.

    Any suggestions?

    If its new as you say I would first take it back to where you got it from for them to have a look at. They should be able to sort you out. Though sadly Halfords are not exactly round for there customer service. If Halfords do refuse you have two options. Ask for a full refund and tell them to come pick the bike back up. Or if you like the bike take it to your local reputable bike shop and get them to have a look. If there is a problem they will be able to sort it for you. Then take a copy of the bill and post it to the Halfords you got the bike from and also a copy to the head office along with a very long letter of complaint asking for them to refund you the cost of the repair. I would also send a copy of your story to watchdog and trading standards.
    You sound like a bundle of fun. I would think Watchdog and Trading Standards is a bit premature when all he's done is go for a ride and fiddle about. Maybe a strongly worded letter to the Mail as well.

    Or stop fiddling, ride them a bit and see. Brakes squeal. Ride, use them hard a few times and then see.
    I don't do smileys.

    There is no secret ingredient - Kung Fu Panda

    London Calling on Facebook

    Parktools
  • cobba
    cobba Posts: 282
    This problem is probably caused by a few things.

    1) The spad spreader that pushes the pads apart is off centre, it pushes more on the outer side of the pad (the part that rubs on the outer edge of the rotor).
    2) The pressure foot that the pad sits against consists of two parts, a 'male' part and a 'female' part which are joined together but don't sit flat against each other.
    3) There is a little bit of play with the two parts of the pressure foot when they are joined together.

    The silver part of the pressure foot in this photo is what the pad sits against, you can see how it doesn't have a flat surface and doesn't seat flatly against the black part of the pressure foot.
    A couple more photos of those parts here and here.

    As there is also a little play in the connection of the two parts of the pressure foot and as they don't seat flat against each other, if you push on one side of the silver part of the pressure foot it will move closer to the black part of the pressure foot but the opposite sides will move further away from each other.
    The same thing happens when the off centred pad spreader pushes against the outer pad, the outer edge of the pad moves away from the rotor while the inner edge of the pad moves closer to the rotor.

    Photo: BB5 Pads
  • Chunkers1980
    Chunkers1980 Posts: 8,035
    This thread is funny. I think the second post is where it is at.
  • logie48
    logie48 Posts: 30
    This thread is funny. I think the second post is where it is at.

    Funny? Yeah, it's hilarious when you get on a bike which howls like hell even when not pressing brakes. The point was regarding the pads. I'm asking others who may know better, should pads be parallel to each other?

    Is there anything wrong with that?

    As a beginner, i'm only looking for advice. The exact reason why I started the thread.
  • supersonic
    supersonic Posts: 82,708
    The brakes operate by bending the rotor - so as the system wears it will appear one pad is out of line with the other. they will not be parallel.

    You should be able to adjust so it does not rub when not in use - you have the pad adjuster and cable tension to play with.

    When that it does, allow to bed in.
  • logie48
    logie48 Posts: 30
    643884_368157489936349_316275528_n.jpg
  • supersonic
    supersonic Posts: 82,708
    It does look rather warped. Take it back for the mechanics to have a close look at.

    Most pads move a bit, or can 'float' (and self level), but there should be more gap than that. What happens if you loosen the cable tension?
  • cobba
    cobba Posts: 282
    edited October 2012
    The pressure foot which the pad pushes against is made of two parts, a 'male' part and a 'female' part.
    Maybe the 'male' part isn't properly seated in the 'female' part.
    Look at the links to photos in my previous post to see what I'm talking about, they're in blue writing.
  • logie48
    logie48 Posts: 30
    cobba wrote:
    The pressure foot which pad pushes against is made of two parts, a 'male' part and a 'female' part.
    Maybe the 'male' part isn't properly seated in the 'female' part.
    Look at the links to photos in my previous post to see what I'm talking about, they're in blue writing.

    Yeah thanks. I think i'll take it in for others to have a look at it.