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Help. I can't stop.

verminvermin Posts: 1,739
edited February 2013 in Commuting chat
The title might have suggested an interesting topic, but sadly not so.

Can anyone explain to me why my brakes don't work. Since swapping out shimano pads for swissstop greens a few months ago, my stopping distance has been so bad it's sometimes scary. It's so bad that I have now snapped a 4 month old cable by pulling too hard on it. The pads are the right way around, on the right sides, etc. The levers and calipers are 105s and worked great with the old pads. The rims are (were) brand new Mavic Ksyrium Elites. What can be wrong?

Is it something to do with the seating? Should there be some toe in/out? If oil has got onto the rims/pads how can that be eliminated completely?

Posts

  • pangolinpangolin Posts: 2,285
    The only way to be safe is to stop cycling vermin. It's for the best. Give it about 4 months.
    Genesis Croix de Fer
    Cube Attain
  • dhopedhope Posts: 6,699
    Should toe in slightly. I tend to put a bit of card at the back of the pad when lining them up so it's a mm or so away from the rim, just enough that the braking builds gradually.

    Give your rim a good clean, fnar. Or new bike, naturally.
    Rose Xeon CW Disc
    CAAD12 Disc
    Condor Tempo
  • veronese68veronese68 Posts: 22,769 Lives Here
    I'm surprised. When I put the Greens on my Kona my stopping distances improved, especially in the wet. They did get worse with a dirty rim though. I would recommend cleaning your rim, but not with WD40.
    If you have got oil into the pad material it's very difficult to completely eliminate it. You need a solvent that won't affect the rubber.
  • verminvermin Posts: 1,739
    Thanks dhope, shall try that tonight. What's the strongest safe-to-use rim/pad degreaser?
    pangolin wrote:
    The only way to be safe is to stop cycling vermin. It's for the best. Give it about 4 months.

    Feeling a bit left behind my scaly friend? Heads up for you: I'm off the bike today and probably tomorrow, and you'll have a 3 week window during March in which to catch up. :D
  • slowbikeslowbike Posts: 8,490
    I was given some Swissstop Greens to replace my standard pads - only had a chance to ride the bike twice so far - but happy with braking - seems better than the previous ones, but they were worn quite badly..
  • mudcow007mudcow007 Posts: 3,861
    i cleaned my bike yesterday (annual clean)

    after lubing the chain up i give the bike a spray with GT85 because A. it smells lovely B. it makes everything super shiny & fresh from the shop look

    i might have sprayed gt85 all over my rims too as my brakes had all the power of a wet lettuce...made my ride home interesting to say the least
    Keeping it classy since '83
  • <hushed voices off> diiiiisssc braaaakes..... :wink::D
    ROAD < Scott Foil HMX Di2, Volagi Liscio Di2, Jamis Renegade Elite Di2, Cube Reaction Race > ROUGH
  • mudcow007mudcow007 Posts: 3,861
    <hushed voices off> diiiiisssc braaaakes..... :wink::D

    i remember when men were real men an used cabled gears....an when they used canti brakes

    pffft modern men, i bet you even moisturize aswell dont you
    Keeping it classy since '83
  • isopropol alcohol on the rims and a file to (slightly!) rough up the rubbers. It's an old cyclocross trick when installing new rubbers before a race.
  • mudcow007 wrote:
    <hushed voices off> diiiiisssc braaaakes..... :wink::D

    i remember when men were real men an used cabled gears....an when they used canti brakes

    pffft modern men, i bet you even moisturize aswell dont you

    LMFAO - at the moment I'm on the MTB/Spiker combo because I ride through all weathers 8) :wink:

    Funny you should say about moisturizer. Mrs MRS said only the other day that I should think about it because my face is looking so weather-beaten. Instead I just use a big tub of MTFU :wink::D
    ROAD < Scott Foil HMX Di2, Volagi Liscio Di2, Jamis Renegade Elite Di2, Cube Reaction Race > ROUGH
  • cyclingpropcyclingprop Posts: 2,426
    isopropol alcohol on the rims and a file to (slightly!) rough up the rubbers. It's an old cyclocross trick when installing new rubbers before a race.

    Everyone else pinches the end and rolls them down. PS that bit shouldn't be considered a race).

    In seriousness, take your wheels out and wash them. Liberally coat the braking track, rim etc with water soluble degreaser, work with an old toothbrush then rinse. Then repeat but with either a technical bike wash (or in my cheap wheels' case, washing up liquid). Rinse thoroughly. Dry any drivetrain parts that get wet (drip dry is fine for the rims).

    Then clean up the pads - again, soap or bikewash and a toothbrush to agitate.

    Its worked a treat for me in the past. And yes, toe in.
    What do you mean you think 64cm is a big frame?
  • slowbikeslowbike Posts: 8,490
    mudcow007 wrote:
    <hushed voices off> diiiiisssc braaaakes..... :wink::D

    i remember when men were real men an used cabled gears....an when they used canti brakes

    pffft modern men, i bet you even moisturize aswell dont you

    LMFAO - at the moment I'm on the MTB/Spiker combo because I ride through all weathers 8) :wink:
    You want to get down south then - us southern softies are back on our roadbikes- Summer has begun!
  • slowbike wrote:
    You want to get down south then - us southern softies are back on our roadbikes- Summer has begun!

    It's always summer down there - it's what makes you sooooo soft :roll: :wink:
    ROAD < Scott Foil HMX Di2, Volagi Liscio Di2, Jamis Renegade Elite Di2, Cube Reaction Race > ROUGH
  • rolf_frolf_f Posts: 15,959
    slowbike wrote:
    You want to get down south then - us southern softies are back on our roadbikes- Summer has begun!

    It's always summer down there - it's what makes you sooooo soft :roll: :wink:

    That's what Icelanders say about you :lol:
    Faster than a tent.......
  • Rolf F wrote:
    That's what Icelanders say about you :lol:

    I think it's more likely for an Icelander to say
    Það er alltaf sumar þarna niðri - það er það sem gerir þér sooooo mjúk
    :wink:
    Nobody told me we had a communication problem
  • team47bteam47b Posts: 6,424
    slowbike wrote:
    You want to get down south then - us southern softies are back on our roadbikes- Summer has begun!

    It's always summer down there - it's what makes you sooooo soft :roll: :wink:


    Winter bike :D
    my isetta is a 300cc bike
  • mtb-idlemtb-idle Posts: 2,176
    Just cos I'm addicted to drinking brake fluid doesn't mean I can't stop anytime like
    FCN = 4
  • slowbikeslowbike Posts: 8,490
    slowbike wrote:
    You want to get down south then - us southern softies are back on our roadbikes- Summer has begun!

    It's always summer down there - it's what makes you sooooo soft :roll: :wink:
    Nah - we just wash our kit more often - with added softener! - anyway - all that extra washing is why we keep having droughts and hosepipe bans. :)
  • PBoPBo Posts: 2,493
    slowbike wrote:
    slowbike wrote:
    You want to get down south then - us southern softies are back on our roadbikes- Summer has begun!

    It's always summer down there - it's what makes you sooooo soft :roll: :wink:
    Nah - we just wash our kit more often - with added softener! - anyway - all that extra washing is why we keep having droughts and hosepipe bans. :)

    Speak for yourself, I never wash my kit.

    Has one advantage...even the cars give me a wide berth!!!
  • Kieran_BurnsKieran_Burns Posts: 10,052
    mtb-idle wrote:
    Just cos I'm addicted to drinking brake fluid doesn't mean I can't stop anytime like

    Châteauneuf .51 a fine tipple....
    Chunky Cyclists need your love too! :-)
    2009 Specialized Tricross Sport
    2011 Trek Madone 4.5
    2012 Felt F65X
    Proud CX Pervert and quiet roadie. 12 mile commuter
  • SketchleySketchley Posts: 4,235
    Back to OP.

    How tight are the block to the rim, I've found that too tight (not rubbing just close) result in underwelming brake performance. Take them back a couple of mm and I get more leverage and better braking. I think this has something to do with mechanical advantage, but I must of been asleep in applied maths and or physics class that day so I don't quite understand it...
    --
    Chris

    Genesis Equilibrium - FCN 3/4/5
  • veronese68veronese68 Posts: 22,769 Lives Here
    Sketchley wrote:
    Back to OP.

    How tight are the block to the rim, I've found that too tight (not rubbing just close) result in underwelming brake performance. Take them back a couple of mm and I get more leverage and better braking. I think this has something to do with mechanical advantage, but I must have been asleep in applied maths and or physics class that day so I don't quite understand it...
    I think it's that as the lever gets closer to the bar the angle your hand is working at improves so you can apply more power.
  • verminvermin Posts: 1,739
    veronese68 wrote:
    I think it's that as the lever gets closer to the bar the angle your hand is working at improves so you can apply more power.

    Which, given that I've just snapped a 4 month old cable, probably isn't the issue.

    I fear the pads are royally screwed with oil, so will probably just buy some more. Wish I wasn't so drawn to those lovely shiny rainbow puddles.

    So, the next question has to be; where can I find the cheapest greens today?
  • cyclingpropcyclingprop Posts: 2,426
    vermin wrote:
    veronese68 wrote:
    I think it's that as the lever gets closer to the bar the angle your hand is working at improves so you can apply more power.

    Which, given that I've just snapped a 4 month old cable, probably isn't the issue.

    I fear the pads are royally screwed with oil, so will probably just buy some more. Wish I wasn't so drawn to those lovely shiny rainbow puddles.

    So, the next question has to be; where can I find the cheapest greens today?

    I've heard of Power Awesome (TM) before, but never Wrist Power Awesome....

    Just saying...
    What do you mean you think 64cm is a big frame?
  • deswellerdesweller Posts: 5,271
    You ought to be able to recover the pads either by giving them a thorough scrub with hot, soapy water or by dressing the surface with emery paper.
    - - - - - - - - - -
    On Strava.{/url}
  • The RookieThe Rookie Posts: 27,747
    Remember to install them toed in (actually it's toed out but everyone call it in) so that piece of card at the rear of the pad (the first bit the rim passes as it rotates), you get more even braking as it corrects out the 'leading edge effect' (Google it if you are uncertain).
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