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Glazed pads

bobbydigitalbobbydigital Posts: 249
edited March 2018 in MTB workshop & tech
You will probably say upgrade the brakes but I have a set of Shimano 396's brakes and no matter what I do they squeel.

I've changed pads, discs, tried cleaning, sanding pads and discs.
Bled them with shimano oil, solid lever feel, no more air coming though.
Allowed pistons to come out during bleed to squeeze any air out.
Bought disc cleaner.
Pedaled with the brakes slightly applied to heat them up.
Done heavy braking cycles.
Calipers are m447's

Rear one has always had issues but now the front is doing it.

v6Y55RD.jpg


Is this an issue with early Shimano brakes?
Pain in the butt, the noise is embarrassing :lol:

Posts

  • cooldadcooldad Posts: 32,904
    Stop putting random faffing and putting censored on your brakes and try soft pads, organic or kevlar.

    ps thats a pic of a rotor, not a glazed pad?

    Do you drag your brakes?
    I don't do smileys.

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  • I put the disc pic as I wasn't sure if it looked normal.

    Pads glazed but clean up with Isopropanol alcohol, work for a while then start to scream. It was with B01S resin pads.

    EaAz606.jpg

    I tried dragging the brakes but will need ear plugs for round 2.
  • The RookieThe Rookie Posts: 27,747
    Dragging the brakes is the worst thing you can do, nice hard stops, about ten in a row.

    Resin pads are bad for squealing at this time of year as they absorb moisture.
  • Bloody hell I have like 15 pairs of those B01S pads, will have to invest in to some other compounds like suggested.

    I've seen people apply the brakes and pedal until the squealing stopped but I'll go for the new compound and see what happens, and the moisture thing makes senses, they would work for a while, a few muddy rides, hose down and they wouldn't be happy.
  • cooldadcooldad Posts: 32,904
    Just clean the rotors with IPA, fit new pads and ride.

    Don't mess with them.

    I've had just about every version of Shimano brakes since they started making them. Never done anything to any of them except normal bike cleaning. A good hose with clean water is all they ever need.

    Some pads squeal under certain conditions. Find ones that work for you. I hate sintered. Other people may differ.

    I don't even bother with bedding in. Just ride to the top of a decent trail, ride down braking normally and they've always been fine.
    I don't do smileys.

    There is no secret ingredient - Kung Fu Panda

    London Calling on Facebook

    Parktools
  • swod1swod1 Posts: 1,639
    Dragging the brakes is one of the worst things you can do when bedding in brake pads.

    As already stated i just do a few hard stops and brakes been fine.

    I'm using semi metallic on my bike and haven't had any issues. the only pads i don't use are kevlar just couldn't get them to bed in properly.
  • slc123slc123 Posts: 407
    I recently fitted some new semi metallic pads to my Guide R brakes. Few hard stops and also absolutely fine. Rode them for a weekend on black runs with no issues.
    Cannondale Trail 27.5 | 2015
    Titus El Chulo 27.5 | 2017
    Trek Slash 9 27.5 | 2015 (building)
  • eric_draveneric_draven Posts: 1,182
    The Rookie wrote:
    Dragging the brakes is the worst thing you can do, nice hard stops, about ten in a row.

    ^^^This^^^
  • swod1swod1 Posts: 1,639
    I also stopped using shimano resin pads as these just easily glazed and made noise. switched to aftermarket pads and no issues. only noise now is in really wet conditions.

    I'd be tempted to change the rotors to something else as the ones used with low end shimano brakes aren't the best and are usually stamped resin only.
  • Keep away from the resins then!

    I got some 506 and 516 brakes, 1 finger ones so might try them and see if they are easier in the long run.
  • JBAJBA Posts: 2,623
    They are Deore brakes. Excellent value and performance so shouldn't be a problem. I have them on my hardtail and they work very well.
    Bed the pads in properly and they will be fine*. All brakes squeal at times, especially in the wet so don't fret about it tooo much.

    *The method that works for me is:
    - Ride at walking pace and slam on brake.
    - Repeat 10 times for each brake.
    - Ride at a decent pace (10mph-ish) and slam on brake.
    - Repeat 10 times for each brake.
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