Results 1 to 5 of 5
  1. #1
    formerly Giantxc
    Reputation: MrXC's Avatar
    Join Date
    Jan 2004
    Posts
    645

    Yet another Hope Mini Question

    As some of you may already realize I'm having a major problem with a 6 month old set of Hope Mini's. I'm not going to rehash the whole situation here since nobody had any thoughts (nor did Hope's USA or UK office), but I have a related question.

    After taking the brakes off so I can use V's while I wait for replacement pads I checked out the calipers. When I pull the lever the 2 pistons rise at different rates. Is this normal for the Mini? I've read a couple of similar questions posted by Hayes users, but no answers. The reason I ask is because my problem has been with the outer pad and that is the piston that rises at a faster rate.

    Anybody???

  2. #2
    mtbr member
    Reputation:
    Join Date
    Jan 2004
    Posts
    318
    Quote Originally Posted by MrXC
    As some of you may already realize I'm having a major problem with a 6 month old set of Hope Mini's. I'm not going to rehash the whole situation here since nobody had any thoughts (nor did Hope's USA or UK office), but I have a related question.

    After taking the brakes off so I can use V's while I wait for replacement pads I checked out the calipers. When I pull the lever the 2 pistons rise at different rates. Is this normal for the Mini? I've read a couple of similar questions posted by Hayes users, but no answers. The reason I ask is because my problem has been with the outer pad and that is the piston that rises at a faster rate.
    I had to go back and read your original post. Even if one of your pistons were totally seized, you should not have had the problems with ripping the pads off the backing! You are unlikely to have a two piston caliper where both pistons move at the same rate. Even minute differences that are within normal tolerances will have one piston moving while the other doesn't ( just make sure it isn't frozen!). The key is having the rotor centred and square in the caliper, so that the pistons will be acting equally on the rotor. I have used the mini's for some time without problems ( after having the mounts faced). Have you taken the caliper apart and cleaned it up thoroughly ( split it apart and pull the pistons and seals out) One of my old Hope calipers had a bunch of machining chafe in one of the piston bores!
    another obvious thing: are you using the original mini rotor? I have had my Lbs try to give me an M4 lightning bolt one instead of the proper wavy mini one

  3. #3
    formerly Giantxc
    Reputation: MrXC's Avatar
    Join Date
    Jan 2004
    Posts
    645
    Thanks OLAK, I'm new to discs so had to ask the basic question. Which actually leads me to another.

    I've taken the brakes off and cleaned them, but I haven't split the caliper halves and cleaned the pistons. I assume doing this will require a bleed? In fact, do I need to drain the fluid first?

    The rotor is the original. I originally went with the Mini precisely because its reviews seemed pretty much faultless.

    Thanks again,

    Mike

  4. #4
    MTB aficionado
    Reputation:
    Join Date
    Jan 2004
    Posts
    950
    I'm with OLAK on this one. Mini's seem to very, very sensitive to caliper/rotor interface. They have to be dead square.... as OLAK suggested get both your fork and frame brake tabs faced by someone who knows what there doing if you haven't already. This is a critical step in getting these brakes to perform and it also will reduce the infamous noise problem.

    If you're shearing off the pads from their metal backing its got to be one of the following: 1) defective pads, 2) a brake pad/rotor alignment problem (which the above mentioned should cure) or 2) there is some imperfection in the rotor that’s catching the pad (these imperfections can be difficult to identify). Get your hobby files out and file all the sharp edges off the rotor.

    Also, with more and more use the pistons will start working better and better, but they never seem to be totally equal… just try to center the rotor as best you can in between the gap you’re given. This is likely a stiff seal problem and should remedy itself with use. However, you can accelerate the process by working the piston seals... remove the pads and repeatedly push them in and out (one piston at a time) while lubing them with brake fluid. I did this and had lots of luck. WARNING: If you choose to do this, do not let the piston come completely out of the caliper or you will be in for a complete re-assembly and re-bleed.

    I've been running my Mini's for nearly two years now and I absolutely love them. However, I do vividly remember being frustrated with them at first. It took about two solid months for them to break-in, but since then I haven't touched them outside of routine maintenance. Also, I'd recommend getting Speedgoat Mini Power Clamp if you don't already have them.

    Just be patient… this can be a fickle process... if you don't get this worked out in the next month, or so I recommend you warranty the brakes so your summer isn't a complete loss.

    Good luck,

    EndUser
    My advice and $3 will buy you nothing more than a tunafish sandwich.

  5. #5
    formerly Giantxc
    Reputation: MrXC's Avatar
    Join Date
    Jan 2004
    Posts
    645
    Thanks EnUser. Is there a facing process for Manitou postmounts? I've heard of this for IS but never postmounts.

    Before I reinstall I'll run a light file over the rotor as you suggested. Sounds like a good idea and perhaps that will do the trick.

    Thanks for suggesting the powerclamp. I picked one of those up when I bought it.

    I'll be patient, but this thing needs to be working by July 4th weekend. I don't want to have to pull my Juicy off the SS for a long weekend trip on the hardtail.

Similar Threads

  1. Brake question: Hope Mini rotors w/ Formula Brakes?
    By AZ-X in forum Weight Weenies
    Replies: 4
    Last Post: 05-20-2004, 08:45 AM
  2. Hope Mini Pad Question
    By MrXC in forum Brake Time
    Replies: 4
    Last Post: 05-11-2004, 12:54 PM
  3. Hope Mono Mini question
    By roee in forum Brake Time
    Replies: 8
    Last Post: 04-19-2004, 05:17 PM
  4. Hope mini question...rotor size
    By aka AK in forum Brake Time
    Replies: 0
    Last Post: 03-17-2004, 07:24 PM
  5. Hope Mini question
    By mtb_biker in forum Brake Time
    Replies: 4
    Last Post: 02-26-2004, 11:10 AM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •