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Hydraulic brake newbie issue!

KitzKitz Posts: 63
edited June 2016 in MTB workshop & tech
So I'm brand new to mountain bikes, coming from roadie experience, so disks and hydraulics are totally new to me.

My Kili flyer 121 has shimmano hydraulic brakes fitted and they are, or were great! Until I washed it!

I like a clean bike after a ride. Wash with muc off, and usually give a good coating of the bike spray afterwards. Gets the water out and looks nice. Problem is, after following my usual routine on this bike (which I've owned for a whole 5 days) and suddenly the brakes don't work! Can pull them right back to the bars, and they squeak and squeal a lot, but do t actually stop the wheels. LBS 100 yards from my house, so over we go. Guy bleeds them, says there fine, but the discs and blocks are contaminated with something and can I leave it with them to take some emery paper to the disks and possibly change the pads!! :cry: :O
All I did was clean it!!

Is this really such a no no with disks? I didn't even spray it directly on them, must have just got a bit on the disks while I was doing the frame which got into the pads when I rode it around afterwards. Do I have to cover the disks if using the bike spray, or keep it off the MTB altogether?? Surely that should be mentioned on the product?

Annoyed! 5 days, 3 rides, broken it already! :roll:

Help. :)

Adam.

Posts

  • lpretro1lpretro1 Posts: 237
    Sounds as though you have sprayed lube onto disks and/or pads. Just washing a bike wouldn't cause that problem (unless u used car wash & wax shampoo. You do not need to squirt spray everywhere - you just need a little lube on pivot points on front & rear derailleurs and chain - do not spray all over the cassette or anywhere else. Bleeding only removes air from a brake - so that was unnecessary. Get new pads - clean the rotors with ipa or other proprietary disk brake cleaner - fit new pads and then go bed them in and ride. Step away from the spray can!!
  • kickaxekickaxe Posts: 446
    To be honest it's common sense that pretty much anything but bike specific brake cleaner and isopropyl alcohol contaminate the brakes, they really don't need to write that on that bottle. I just use a plastic bag over each caliper and disk when cleaning my bike with anything other than water and plain soap. Also I use them when lubing my chain or when looking after my suspension components.

    You should take out the wheel and the pads, clean both disks and pads with alcohol (pharmacy), and then sand a very thin layer off the pads, maybe a fifth of a millimeter. Put everything together, and after 10 minutes of accelerating and braking everything should work, This has worked for me several times.
    -Cube Acid 29" 2013
    -A new Giant Trance 3 2015!
  • KitzKitz Posts: 63
    It is a bike specific spray, made by muc off, called "bike spray", and I didn't even spray it directly on the disks. I did lube the chain only, again, with a muc off bike chain lube, but none any where near the brakes.

    Must have been the bike spray. Wouldn't have been the cleaning spray which is meant to be sprayed everywhere.

    Yes, obviously common sense only to use bike specific products on a bike! :)
  • KitzKitz Posts: 63
    Good idea about covering them. Shall use that tip, and will look into a specific disk brake cleaner. Any good ones you can recommend?
  • KajjalKajjal Posts: 3,404
    As above contaminated discs and rotors. Any oil or similar on pads or rotors removes friction and stops brakes working. When cleaning the bike cover discs / brakes so nothing gets on them. Solution is degrease / clean rotors and fit new pads. There are various disc cleaners on sale. I used muc off disc cleaner which worked well.
  • KitzKitz Posts: 63
    lpretro1 wrote:
    Step away from the spray can!!

    But it looks so shiny! 8)

    Seriously though, thanks. Good advice. Better save the finishing spray for the road bike I think.

    Oh dear, and by googling it I find the disclaimer that says "braking surfaces should be masked when using this product!"

    My bad, lesson learnt. Won't be doing it again! :oops: :oops: :oops:
  • KitzKitz Posts: 63
    Kajjal wrote:
    As above contaminated discs and rotors. Any oil or similar on pads or rotors removes friction and stops brakes working. When cleaning the bike cover discs / brakes so nothing gets on them. Solution is degrease / clean rotors and fit new pads. There are various disc cleaners on sale. I used muc off disc cleaner which worked well.

    Thanks. I'll get some specific disk cleaner.

    So would you use the muc off all over cleaner on the disks or is it really as strict as just water and disk cleaner only? Seen a couple of vids on cleaning, and they pretty much just go for it.
  • cooldadcooldad Posts: 32,904
    Clean the rotors with IPA, get new pads, and don't clean the brakes with anything except water. Spray them to get grit/mud out and then just leave them alone.


    99.9876865432% of all brake issues are caused by people faffing with their brakes.
    I don't do smileys.

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  • JBAJBA Posts: 2,561
    Much Off Bike Cleaner (the pink stuff) is fine for everything on the bike.
    It's the Bike Spray and MO94 that you have to keep away from the brake pads and rotors.
    “Life has been unfaithful
    And it all promised so so much”

    Giant Trance 2 27.5 2016 ¦ Bird Zero Mk1 ¦ Giant Revolt Advanced 2 2019 ¦ Giant Anthem 3 2015 ¦ Specialized Myka Comp FSR 2009
  • KitzKitz Posts: 63
    JBA wrote:
    Much Off Bike Cleaner (the pink stuff) is fine for everything on the bike.
    It's the Bike Spray and MO94 that you have to keep away from the brake pads and rotors.

    Thanks. Yeah that seems to be the lesson of the day! :oops:
  • POAHPOAH Posts: 3,369
    muc off bike cleaner (pink stuff) fucks pads up as well. had to clean and sand my bro in laws discs and pads to fix them after he cleaned the bike.
  • RockmonkeySCRockmonkeySC Posts: 15,247
    cooldad wrote:
    Clean the rotors with IPA

    Indian pale ale?
  • KajjalKajjal Posts: 3,404
    cooldad wrote:
    Clean the rotors with IPA

    Indian pale ale?

    Also use a chicken madras to go with the IPA.
  • cooldadcooldad Posts: 32,904
    cooldad wrote:
    Clean the rotors with IPA

    Indian pale ale?

    Drink enough and you don't need brakes.
    I don't do smileys.

    There is no secret ingredient - Kung Fu Panda

    London Calling on Facebook

    Parktools
  • RockmonkeySCRockmonkeySC Posts: 15,247
    cooldad wrote:
    cooldad wrote:
    Clean the rotors with IPA

    Indian pale ale?

    Drink enough and you don't need brakes.

    Better for you than drinking isopropyl alcohol.
  • swod1swod1 Posts: 1,639
    What were you doing with the bike spray?

    Next time spray some on a clean paper towel or rag and wipe over the frame, I do this with a little gt85 stops mud from sticking to frame.

    when cleaning my bike I just spray some water over discs and then wipe the discs with a clean paper towel.
  • larkimlarkim Posts: 2,282
    POAH wrote:
    muc off bike cleaner (pink stuff) f***s pads up as well. had to clean and sand my bro in laws discs and pads to fix them after he cleaned the bike.
    Is this now the received wisdom about MucOff cleaner? I've been using it liberally all over the bike (and telling son to to do the same) safe in the knowledge that MucOff doesn't cause any problems with pads or discs. If we're best avoiding the discs / pads then that's what we'll do.
    2015 Canyon Nerve AL 6.0 (son #1's)
    2011 Specialized Hardrock Sport Disc (son #3s)
    2013 Decathlon Triban 3 (red) (mine)
    2019 Hoy Bonaly 26" Disc (son #2s)
    2018 Voodoo Bizango (mine)
    2018 Voodoo Maji (wife's)
  • KitzKitz Posts: 63
    larkim wrote:
    POAH wrote:
    muc off bike cleaner (pink stuff) f***s pads up as well. had to clean and sand my bro in laws discs and pads to fix them after he cleaned the bike.
    Is this now the received wisdom about MucOff cleaner? I've been using it liberally all over the bike (and telling son to to do the same) safe in the knowledge that MucOff doesn't cause any problems with pads or discs. If we're best avoiding the discs / pads then that's what we'll do.

    Far be it from me to advise on this, as the one who started the thread after knackering up my own brakes, but it has made me spend a fair amount of time looking into this, and from now on this is what I will be doing. - Cleaning the whole bike, except the brake callipers and rotors with the pink stuff, cleaning the rotors and callipers a with a squirt of disk brake cleaner and water, and bagging the whole brake setup if I pluck up the courage to use the bike spray on it again!
  • kickaxekickaxe Posts: 446
    Make sure it's bike specific brake cleaner! They'll be ruined if it's not
    -Cube Acid 29" 2013
    -A new Giant Trance 3 2015!
  • KitzKitz Posts: 63
    kickaxe wrote:
    Make sure it's bike specific brake cleaner! They'll be ruined if it's not

    This is the stuff I'll be using.

    http://www.wiggle.co.uk/muc-off-disc-br ... 60128362uk
  • Yeah the muc-off specific disc brake cleaner is good, use it all the time
  • swod1swod1 Posts: 1,639
    that stuff made some shimano resin pads crumble to bits on my bike so haven't used it since even though it said it was fine to use near brake pads.
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