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  1. #1
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    New question here. XTR ''STI'' no matter what i try the lever still touches the grip

    First I used every trick i know from many years of bicycles and motorcycles plus a few I learn reading this pages in the last few days and even then i can not get full power out of my front brake, (the rear one works great)..

    What do I do next, sell them..??
    Braided lines..?

    I have new pads and rotor and even then the front will not stop the bike, yes I'm kind of a Clydesdale with a long heritage of HOPE this brakes and they always stop me even the really old single piston ones, or I'm just asking to much from this single piston things...??

    Actually the symptom is kind of weird, it feels like the lever is reaching full travel and then like a "Cam" gets a little softer until it touches the grip.

    thanks in advance I'm puzzle.

  2. #2
    ballbuster
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    Brake lines?

    Quote Originally Posted by patineto View Post
    First I used every trick i know from many years of bicycles and motorcycles plus a few I learn reading this pages in the last few days and even then i can not get full power out of my front brake, (the rear one works great)..

    What do I do next, sell them..??
    Braided lines..?

    I have new pads and rotor and even then the front will not stop the bike, yes I'm kind of a Clydesdale with a long heritage of HOPE this brakes and they always stop me even the really old single piston ones, or I'm just asking to much from this single piston things...??

    Actually the symptom is kind of weird, it feels like the lever is reaching full travel and then like a "Cam" gets a little softer until it touches the grip.

    thanks in advance I'm puzzle.
    Is your reservoir the highest point in the system? When I switched to H-Bars, my brake lines actually arced up slightly then down to the frame, and this is exactly where any air in the system would get trapped. I had the same exact issue you had... air bubbles in the lines, no matter how well I bled them. It's nearly impossible to chase all of the air out of the reservoir, and any air left is going to migrate to the highest point in the system.

    Also, it's very important to bleed the brakes with the yellow plastic block in place of the brake pads.

    Have you checked for leaks in the system? These are pretty much closed systems. If air is getting in somewhere, fluid is seeping out. When you bleed the brakes, make sure you fill up the reservoir all the way, and then slowly roll the bladder in to displace any air before you replace the cap.

    I'm also a clyde, and also use Hope brakes as well as XTR. XTRs aren't quite as good as Hope, but they're close. The only thing that I really don't like about XTR is that they are not serviceable. Once the seals go in the lever or the caliper, they are trash. Hope, you can rebuild yourself!

  3. #3
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    Quote Originally Posted by pimpbot View Post
    Is your reservoir the highest point in the system? When I switched to H-Bars, my brake lines actually arced up slightly then down to the frame, and this is exactly where any air in the system would get trapped. I had the same exact issue you had... air bubbles in the lines, no matter how well I bled them. It's nearly impossible to chase all of the air out of the reservoir, and any air left is going to migrate to the highest point in the system.
    Yeap, perfectly flat reservoir (45deggre angle of the lever) and I try to "pump" (push) from the bottom, I even use a professional pump I use on my motorcycle to replenish the fluid, and many other tricks I just don't see how bubbles can be anywhere, then again that most be the problem.

    Also, it's very important to bleed the brakes with the yellow plastic block in place of the brake pads.
    Yes I did that too

    Have you checked for leaks in the system? These are pretty much closed systems. If air is getting in somewhere, fluid is seeping out. When you bleed the brakes, make sure you fill up the reservoir all the way, and then slowly roll the bladder in to displace any air before you replace the cap.
    Affirmative, no leaks anywhere even use talcum powder to check for micro leaks.
    I'm also a clyde, and also use Hope brakes as well as XTR. XTRs aren't quite as good as Hope, but they're close. The only thing that I really don't like about XTR is that they are not serviceable. Once the seals go in the lever or the caliper, they are trash. Hope, you can rebuild yourself!

    I don't pretend the XTR's are going to work as well as my multi piston HOPE's, I just want to be able to tell the difference when the brake is applied, actually is not that bad, the brake does work a little but is no way i can trust it on the trails

  4. #4
    ballbuster
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    Maybe that's the issue

    Quote Originally Posted by patineto View Post
    Yeap, perfectly flat reservoir (45deggre angle of the lever) and I try to "pump" (push) from the bottom, I even use a professional pump I use on my motorcycle to replenish the fluid, and many other tricks I just don't see how bubbles can be anywhere, then again that most be the problem.
    IIRC, the instructions from Shimano say to bleed from the top.

    I use a bottle at the bottom with some 1/8" clear poly hose form the hardware store into a little bottle zip tied to the frame.

    I mean, I personally do both, but maybe following the instructions to the letter might be worth trying.

    And yeah, I was comparing the Mono Minis on my singlespeed to the XTRs on my geared bike. They both have about the same thermal capacity, that is, I can overheat them in about the same way on the same hill if I really tried.

  5. #5
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    Quote Originally Posted by pimpbot View Post
    IIRC, the instructions from Shimano say to bleed from the top.

    I use a bottle at the bottom with some 1/8" clear poly hose form the hardware store into a little bottle zip tied to the frame.

    I mean, I personally do both, but maybe following the instructions to the letter might be worth trying.
    I did not have the instructions, do you know where I can find them...??

    but I did try to bleed them from the top first, also sucking from the bottom, vibrating, "Hammering", etc in short every way I know

    And yeah, I was comparing the Mono Minis on my singlespeed to the XTRs on my geared bike. They both have about the same thermal capacity, that is, I can overheat them in about the same way on the same hill if I really tried.
    Nice to know, for now I guess I keep them.

  6. #6
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    Okay i re-bleed the brakes the "shimano way" and i still get the same results.

    Man this is getting kind of annoying.

  7. #7
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    I try my "Bottom up pressurize" method again this morning and the lever achieve full power, the only problem is I have no idea why since I did the exact same thing I try three times before with no results.

    Well at least now I have a front brake and a really good one at that.

  8. #8
    ballbuster
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    Quote Originally Posted by patineto View Post
    I try my "Bottom up pressurize" method again this morning and the lever achieve full power, the only problem is I have no idea why since I did the exact same thing I try three times before with no results.

    Well at least now I have a front brake and a really good one at that.
    When I was having issues, I once tried putting the bike up in the workstand, front end up in the air, bars turned sideways and held that way with a bungee cord with the reservoir at the highest point with the brake line almost straight up from the rear brake to the lever. I left it like that overnight. Then I gave the pistons an extra push apart to squirt out anything that would have collected at the banjo connector.

    Then put the bike back on the ground and make sure there is the correct amount of fluid, and all the air is chased out.

    It turns out I had two issues. One, the brake lines arced up from the reservoir, then back down, making them the highest point in the system. Two, my rear brake caliper seal started failing, letting a bit of air in the system. My Hope Mono Mini caliper needed a rebuild.

  9. #9
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    Had a similar problem on a set of front 965 xtr brakes. Would pull the lever, it would firm up but lever kept going all the way to the grips. Tried every which way to bleed the brakes but no avail. Brakes worked fine though, xc use.

    Problem was that the brake hose inner had split and the oil was seeping out between the inner and the outer protective sheath when some power was applied. When you released the lever the oil would return. You could feel it by hand by holding the area that was split and pumping the brakes, although not really noticable to the eye unless you really look for it. The hose expanded like a small ballon, though no oil was leaking. Mine was split right next to the banjo on the caliper. New hose fixed the problem.

  10. #10
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    Quote Originally Posted by apostolos View Post
    Had a similar problem on a set of front 965 xtr brakes. Would pull the lever, it would firm up but lever kept going all the way to the grips. Tried every which way to bleed the brakes but no avail. Brakes worked fine though, xc use.

    Problem was that the brake hose inner had split and the oil was seeping out between the inner and the outer protective sheath when some power was applied. When you released the lever the oil would return. You could feel it by hand by holding the area that was split and pumping the brakes, although not really noticable to the eye unless you really look for it. The hose expanded like a small ballon, though no oil was leaking. Mine was split right next to the banjo on the caliper. New hose fixed the problem.
    thanks for sharing your experience, I'm just glad that was not my case.

  11. #11
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    I think I will like to upgrade my hoses after reading the comments from Apostolos, where do I look for them, stock/aftermarket, what is best..!?

  12. #12
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    I've had this problem twice with 785's. With the yellow block between the pistons I would get good lever feel but when I would install the rotor and run the pads out it would stay spongy. What would happen in my case at least is the pads would come out hit the rotor and retract to much causing a little extra pad travel and to much throw in the lever. To fix it I had to take the wheel back out and run the pistons in a ways and then install the wheel. Just an idea anyways.
    And I love beer!!

  13. #13
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    Quote Originally Posted by bdundee View Post
    I've had this problem twice with 785's. With the yellow block between the pistons I would get good lever feel but when I would install the rotor and run the pads out it would stay spongy. What would happen in my case at least is the pads would come out hit the rotor and retract to much causing a little extra pad travel and to much throw in the lever. To fix it I had to take the wheel back out and run the pistons in a ways and then install the wheel. Just an idea anyways.
    This is exactly what worked for me and my xtr trail brakes. I also had to change brake hose to jagwire hose because the stock shimano hose was leaking at the crimp next to the caliper. My front pads got oil on them from the leak. I was able to save them by burning the pad material for 20 seconds on the stove, then rubbing the 2 pad surfaces together, then burning again. Leave the pad surface burnt and install, then brake in pad like you normally would. I went from very weak front brake to crazy strong.

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