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  1. #1
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    Caution;  Merge;  Workers Ahead! mega loss of power, add water=mega increase in power!

    i have an XTR caliper and xt levers on my 06 specialized enduro but the front brake has lost most of its power. I changed the very dirty mineral oil and re-bled them, sanded the rotor and pads with fine sandpaper and wiped both with methylated spirits. After a ride without a good front brake, i gave the bike a wash and got water all over it, i then rode around my yard and nearly went over the handlebars as i had massive power in my brake! i'm not sure why it does this and would like to know the next step to make the brake work without getting it wet everytime i go down the hill!
    thanks
    Last edited by turtlewax; 04-12-2010 at 02:24 PM.

  2. #2
    Pimpmobile
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    You did all that and THEN it had more power?

    Are you sure you can attribute it to water and not bleeding, sanding, cleaning?

  3. #3
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    sorry i didn't make it clear, i bled, sanded and cleaned and had no difference in the brakes performance, the following day after a ride i washed it and then found it had more power

  4. #4
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    Quote Originally Posted by turtlewax
    sorry i didn't make it clear, i bled, sanded and cleaned and had no difference in the brakes performance, the following day after a ride i washed it and then found it had more power

    Probably the brakes were still bedding in then you washed it and everything started working...

    Water usually reduces brake power, unless your brakes are overheated to start with...

  5. #5
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    Happens in my truck the same too. If its been sitting in the rain the slightest touch on the brakes makes them uber grabby. I have to tell my passengers to be warned of the unintended brake check! After a few stops they even out and become normal, I am assuming that would happen on your bike too

  6. #6
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    yes after a bit it goes back to what it has been like BUT with no power it does squeak/howl when its dry, i would have thought that meant they were contaminated but ive de-contaminated the disk and rotor so i dont know what to do now.
    Because i bought the bike second hand im not sure how old the brake is, but the bike is an 06 so if the brake is that old would the internals have failed? the brake has been like this ever since ive been in posession of it.
    Last edited by turtlewax; 04-14-2010 at 03:29 AM.

  7. #7
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    My rear brake is the same way. I don't know why it is like that either but it is driving me pretty crazy.

  8. #8
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    It happens a lot with sintered pads, they can brake better when wet.

    MBUK did mechanical tests on a range of brakes, some rocketed in power when wet.
    Mine do.

  9. #9
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    Quote Originally Posted by CaveGiant
    It happens a lot with sintered pads, they can brake better when wet.

    MBUK did mechanical tests on a range of brakes, some rocketed in power when wet.
    Mine do.

    I agree, sintered are great wet. That's why i run them in the winter, and switch to Swiss Stop for the dryer seasons.
    Lead by my Lefty............... right down the trail, no brakes.

  10. #10
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    hmmm, good to know its not just me then! i got fed up with my brake so i got a friend to service them and then im going to sell them to our other friend. instead i just ordered some avid elixir r brakes! they're going really cheap (116! ) on ebay and they can deliver to europe and the USA

  11. #11
    DGB
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    You say you've de-contaminated the pads and rotors, both with Methylated spirits. If the pads are contaminated, that's not going to do much for them. You should scorch the pads over an open flame until they get red hot and start to smoke/burn-off the offending contaminant(s). Make sure you clean the rotors again before using the brakes.

  12. #12
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    Quote Originally Posted by spazzy
    Happens in my truck the same too. If its been sitting in the rain the slightest touch on the brakes makes them uber grabby. I have to tell my passengers to be warned of the unintended brake check! After a few stops they even out and become normal, I am assuming that would happen on your bike too

    The reason for that in your truck is because your rotors are steel. After setting & getting moisture on them they will have a fine layer of surface rust on them making them grabby until it is worn away. Bike rotors are stainless so the surface rust is a non issue with them.

  13. #13
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    ok will do that for him, thanks. sounds fun anyway!

  14. #14
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    the chances are that your brake pads were oiled up at some point and that's why you didn't have hardly any power when they were dry. i have some Juicy 5's and the same thing happened to me, i tried burning the oil out among other things and nothing worked but then a kid told me to mix up some really fine sand in some water then drench the brakes and ride down a big hill with my brake on a little. i did this and like you said i got massive amounts of power from them but not long after the water dried up it was right back to the way it was before. the only thing i have found that works for getting power back into your brakes is to change your pads and wash your rotor in some boiling water than through it in the wash with some cloths you don't care about much ( MAKE SURE THEY ARE NOT COVERED IN OIL ) then sand them down and wash some more.

  15. #15
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    hmmm yeah thats exactly the same as me . i will try this method, eventually they will work!

  16. #16
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    Quote Originally Posted by Mike'sfootwash
    the chances are that your brake pads were oiled up at some point and that's why you didn't have hardly any power when they were dry. i have some Juicy 5's and the same thing happened to me, i tried burning the oil out among other things and nothing worked but then a kid told me to mix up some really fine sand in some water then drench the brakes and ride down a big hill with my brake on a little. i did this and like you said i got massive amounts of power from them but not long after the water dried up it was right back to the way it was before. the only thing i have found that works for getting power back into your brakes is to change your pads and wash your rotor in some boiling water than through it in the wash with some cloths you don't care about much ( MAKE SURE THEY ARE NOT COVERED IN OIL ) then sand them down and wash some more.
    Interesting ideas

    Oil-free is oil-free.... i don't see much sense in boiling water or throwing in the laundry....

    Stainless steel cleans easy enough with a little soap and water... rinse thoroughly. Wipe with isopropyl alcohol on a clean rag if you want to be sure....
    You better just go ahead and drop that seatpost down to the reflector... the trail gets pretty rough down there.

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