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  1. #1
    Giant Anthem
    Reputation: 2fst4u's Avatar
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    2008 XT disk brakes-so far no good!

    I got a new Giant anthem for this racing season-it came with 2008 model XT brakes. My first big ride of the year was yesterday and the rear (160mm) felt squishy and had hardly any power-the front (180mm) was much better.

    What gives here? My old hayes 9 brakes on my heavier giant trance were immensely better. (both 160mm)

    Should I...

    replace pads

    rebleed

    buy different brakes if these are going to be problematic anyway?

    I do have xtr centerlock rotors which may be a bit narrow.

    Any comments??

    Thanks.

  2. #2
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    start with bleeding them,mine work great.......as with most brakes the factory bleed blows !!!!

  3. #3
    ups and downs
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    Did you bed them in or are they out of the box new?
    I'm a member of NSMBA and IMBA Canada

  4. #4
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    If he went on a 'big ride,' the brake pads should be bedded in. I am guessing the problem has more to do with the brakes needing to be bled. Pick up some mineral oil and follow shimano's instruction on how to bleed the brakes. It should not take you more than half an hour and it's really easy to do.

    I'm not sure of the exact model your brakes are, but do they have the free-stroke adjustment screw?

  5. #5
    Giant Anthem
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    I got them new and they now have about 5-8 hours on them-

    They have a free stroke screw which I played with to get them as good as they could get.

    Hopefully bleeding them will help. I'll try this asap

    Thanks guys

  6. #6
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    Was it cold? They are great when it's warm, around 0 degrees (Celsius) they work much worse. Something to do with sticky seals - probably fixable on warranty.

  7. #7
    DGB
    DGB is offline
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    Quote Originally Posted by flow350
    If he went on a 'big ride,' the brake pads should be bedded in.
    Not necessarily. You can glaze the pads if you don't bed them in properly and they'll feel crap.
    I am in agreement that it's most likely that they need to be bled. The brakes are M775 XT if they're 2008. Take your time with the bleed and don't forget to use the yellow bleed blocks.

  8. #8
    Giant Anthem
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    glazed

    It was warm out so none of the "cold problems" that others mentioned in the reviews. Should I lightly sand the pads to remove possible glazing? The front works much better than the rear, why would just one set be glazed and the other not?

    Th issue here is that I had hayes 9 hydro's for 2 years without one issue and the braking was very firm and I could lock up the rear wheel to kick around turns. Why these xt's need tlc right out of the box is a bit crazy compared to the hayes-I'll give em a chance though guys.

  9. #9
    Giant Anthem
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    need special kit??

    Do I need any special parts to shorten the brake lines?

  10. #10
    EDR
    Reputation: eatdrinkride's Avatar
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    Quote Originally Posted by 2fst4u
    Do I need any special parts to shorten the brake lines?
    You'll need a new olive (compression fitting). You can cut out and re-use the barb. The lbs should have olives.

  11. #11
    EastBaySteez
    Reputation: Freerydejunky's Avatar
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    Bleed the brakes.

    I doubt you glazed the pads.

    Dont use brakes? I rarely use rear brake unless its to skid and tear up trails. I mean to slow down?

    My XT's are the cats meow. <3 <3 <3
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  12. #12
    Giant Anthem
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    XT's are a headache

    Alright guys-I started the process to re bleed the rear brake (faulty one) and realized that it is just as firm as the front. No air bubbles; and it squeezes up just as firm as the front. I realized this after I took off the reservoir cover and followed the exact directions to re bleed and after buying finish line oil. So I put it all back together without a full re bleed and the levers pull identically firm which proves that there is no air in the system-

    So-tell me about this "burn in period". The brakes and bike had about 5 hours on them before this 2 hour ride. It was also a lot of really step hills that may have done something to the pads.

    So I sanded them down which seemed to remove the glaze and now will have to start from scratch with the "burn in period" any suggestions on this??

  13. #13
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    If the pads had a glaze on them then they were almost certainly contaminated some how! I have the same bakes as you and have been pretty impressed, then last week for no apparent reason (maybe over spray on the bike spray!) they suddenly had no power and were squealing.

    I cleaned the rotor with de greaser and put in new pads and all is fine again. I can only assume this is your issue as well!

    So, my advice is to clean the rotors and replace the pads! It may be worth taking them back to the shop you brought them from!

    Hope this helps, bar the mixed reviews on this forum, when they are set up well they are great brakes, mine have been used pretty hard for a year and have no issues apart from this one, I have even used them in -10C, with no issue!
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  14. #14
    DGB
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    You may have gotten some contaminant on the pads and/or rotor too. Try flaming the pads over a gas flame and see if there is any smoke that comes off them and clean the rotors with Isopropyl Alcohol (IPA) or some Vodka.
    To bed them in drag the brake until you notice an improvement in the braking, let go and let it all cool, then perform about 20-30 hard stops from about 20km/h (~12mph). The pads should be ready to go.
    Initially, you may notice some drag but as they begin to wear that will go and the braking performance should improve. I've just replaced my pads on mine and did the above and they're working great again.
    Good luck.

  15. #15
    'All over it!'
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    I am no expert, but I have not touched my wifes 2008 XT brakes since I put them on her Yeti 575. The only upgrade I made at the point of purchase was XTR rotors front and rear. The brakes are nothing short of phenomenal! I would suggest a re bleed or perhaps for piece of mind - some new pads.

    From experience with my formulas, time spent on a decent bleed pays dividends. Good luck.

  16. #16
    Giant Anthem
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    2008 XT disk brake problem solved

    Problem- My rear 2008 XT brakes seemed to lose 90% power on my first big ride on the new brakes last week. (terrain was very, very steep)

    What didn't work- Rebleeding. I re bleed the rear brakes and this didn't fix the rear brake issue-still felt like crap. There were no air bubbles.

    Remedy- Sanded down the pads with 100 grit sandpaper and cleaned them with denatured alcohol. I then proceeded to bed them in carefully when I rode the next time-I simply just applied light to medium pressure and didn't come to a full stop on the first lap.

    Notes- I have resin pads installed-I didn't know this but they don't have quite the bite as metal pads. But they do modulate better. I will try the metals next time I replace as I want to be able to have stronger braking power like my old hayes 9, which by the way were awesome. So, I hope these brakes live up to the XT name, and I hope to be happy with them once I learn the strenghts and weakness's.

  17. #17
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    Yeah because I keep hearing from people that these are sweet and modulate well. I have a chance to get them for a new build for cheap and it sounds like the way to go. Are the 09s any better than the 08s ?

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