Tektro Draco Seal Problem

ps4customgamer
ps4customgamer Posts: 34
edited October 2014 in MTB workshop & tech
I fitted some tetro draco brakes onto my second bike a few months at the time I noticed they didnt stop as effectively as my other brakes. I thought nothing of it at the time however I tried topping up the mineral oil but when I put the cap back on at the handlebars I noticed air was coming out around one of the screws. Obviously the seal isnt very good but i dont even know where to look for a seal.
Can anyone tell me how to fix this

Comments

  • tedtheshed
    tedtheshed Posts: 21
    Hi,

    When you say they don't stop as effectively, is there a lot of lever travel? Or is the lever solid, but the brakes don't seem to be very effective?

    Is it the little bleed screw hole on the reservoir cap where you think air is leaking out?

    You can buy the diaphram (the seal underneath the brake reservoir lid) from here if you need to http://shop.upgradebikes.co.uk/Catalogu ... aco-Spares

    I've got Dracos on my bike and when I've bled them I've always done it from the bottom up (adding fluid at the caliper, then it escapes through the bleed screw hole at the top (where you are describing air bubbles). I'd imagine if you're filling from the top, you won't be able to get quite as much fluid in as if you're doing it from the bottom (with the lid on and a bleed nipple connected).

    A lot of people will recommend you avoid bleeding brakes nowadays, but I've found the Dracos need it doing fairly regularly (when you turn the bike upside down air seems to get into the system whether you pull the lever or not).
    Could be worth buying a proper bleed kit - I got mine from Epic (can find a link if you need it).
  • ps4customgamer
    ps4customgamer Posts: 34
    Ive had this problem since I first bought and fitted them to my bike, they were suppose to be pre blead from the factory so i was surprised when I realised they seemed to have air in them. I took the cap off the other day to try and burp the breaks rather than a full bleed and topped up the mineral oil. It was only when i reassembled and there was oil on the top of the cap that i realised that air bubbles were coming out of the seal around the screw.
    http://shop.upgradebikes.co.uk/imagecac ... 00x800.jpg
    The screw air seems to come out of is number 6 on the left hand side in the picture.
  • The Rookie
    The Rookie Posts: 27,812
    Number six are the 2 bolts for the clamp, you sure it's leaking round one of them?
    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.
  • ps4customgamer
    ps4customgamer Posts: 34
    When theres oil on top of the clamp I can see air bubbles come out from around the bolts when the brake levers are pulled
  • The Rookie
    The Rookie Posts: 27,812
    Maybe it's just squid going out the gap between bars and clamp, I doubt any air could get into the brakes and then back out there, clean it up and no air bubbles!
    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.
  • ps4customgamer
    ps4customgamer Posts: 34
    Oil comes out, air goes in, I just need to sort the seals around these screws.
  • The Rookie
    The Rookie Posts: 27,812
    The clamp is a long way from any oil though, there is the solid metal section from the reservoir and piston section to the clamp, if it is leaking out at the clamp it's defective (majorly so) and fluid is leaking throuigh what should be solid metal, there is no seal at those bolts as they don't (or at least shouldn't) go near the fluid.

    If oil is coming out and air was going in it - it wouldn't make air bubbles!
    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.
  • ps4customgamer
    ps4customgamer Posts: 34
    Im away at the moment but when I get back Ill be able to post some photos or a video. Needs sorting omg
  • ps4customgamer
    ps4customgamer Posts: 34
    You can see in the first four seconds of the video their are air bubbles coming out from around the bolt. Not really sure what I can do both bolts are tight

    http://youtu.be/Vzh-Um3U-14
  • cooldad
    cooldad Posts: 32,599
    Those are not the clamp bolts though, it's the bolts holding the reservoir lid on, so new seals.
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  • supersonic
    supersonic Posts: 82,708
    There is an air gap above the reservoir seal (there has to be so the thing can expand) - air is supposed to come out. There is also a breather hole if you look carefully.
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  • The Rookie
    The Rookie Posts: 27,812
    Sounds like you got oil in the expansion volume and it's come out the air bleed hole as it should......user error.

    The poor braking is probably oil you've spilt on the discs and pads!
    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.
  • ps4customgamer
    ps4customgamer Posts: 34
    The discs and pads dont have oil on them as the bike hasnt been used much yet and ive checked.

    How should I go about fixing this problem, new seals?
  • The Rookie
    The Rookie Posts: 27,812
    No, remove the cap, clean it and refit, making sure it's cleaned of excess oil. If you have damaged the diaphragm seal you will need a new 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.

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