Viewing 40 posts - 1 through 40 (of 175 total)
  • Whats up with my XT brakes?
  • edward2000
    Free Member

    When i pull the lever, it obviously travels until the pads made contact, but when i release them and pull them again straight away, the lever doesn’t travel as far, about half the distance as it initially travelled. This can be a bit dangerous at times!

    A bike shop bleed didnt fix it either.

    Any ideas?

    twiglet_monster
    Free Member

    Interesting – I seem to get the same behaviour with my SLX version..

    TM

    legend
    Free Member
    scotroutes
    Full Member

    One of my M8000s was behaving like this until I bled it properly. The only problem I’m currently experiencing is delayed braking in sub zero temperatures, mostly when the rotors are also wet. Might try a different compound pad. Maybe ice-tech is just too effective!

    tom.nash
    Full Member

    Exactly the same with XTs, really dangerous! No matter how many times I bleed it (and I’m a mechanic). Back to Hopes very soon!

    Daffy
    Full Member

    This was just one of several reasons why I ditched my 3 sets of XTRs for a return to Hope Tech.

    ndthornton
    Free Member

    Id also like to know what the answer to this is…

    Have a set of SLX’s on my winter bike which are without doubt the best brakes Iv ever owned (NOTE: previously hope fan boy – thought they were ace but think they are distinctly average now in comparison).

    Liked the SLX so much I bought some XTR for my posh bike. No so happy with these – they are just as powerful as the SLX but suffer from the pump up problem stated above. The first pull goes almost all the way back to the bars and subsequent pulls are just about right. Power is good on both pulls with no sponginess at all so I find it hard to believe their is air in the system. But you always need to pull the lever twice which is annoying and run the lever further from the bars than I would like.

    Both brakes bled by me using exactly the same method (syringe at the bottom – cup at the top and lots of lever pulling / waggling etc). Iv actually bled the XTR brakes twice as I assumed I made a mistake the first time but to no effect.

    So I don’t get it.

    tom.nash
    Full Member

    Anyone from Madison on this forum..?

    jonnym92
    Full Member

    I am getting the same on my SLX brakes, the rear only. Bled them numerous times, new pads.. Not sure what the next step is really.. bar new brakes. I like them other than that.

    sharkattack
    Full Member

    This has been discussed on here a lot there’s clearly a problem. I’m sick of talking about my Saints so I won’t.

    I’ll just say that on a DH bike, on an Alp, you really need to know that your brake lever won’t hit the bar on the first pull. Constantly dabbing them to make sure they’re still there is no way to ride.

    duir
    Free Member

    I think this is most people’s main gripe with Shimano brakes, too much lever throw no matter what you do and especially bad on initial pull. The other big downside is that they are throw away units and small parts can’t be sourced. Shame really as otherwise they are really good.

    scotroutes
    Full Member

    Anyone wanting to ditch their “non-functioning” Shimano brakes can send them to me for re-use disposal.

    endurokid
    Free Member

    All of the above happen to me with my XT and SLX, although truth be told they haven’t had a bleed since I bought them, but they have never great from the start.

    They seem more powerful but I kind of wish I kept my Tech M4’s that I sold on here, they felt awesome.

    Goldigger
    Free Member

    I must be one of the lucky people then. All my shimano brakes have worked fine. Bleeding them is a work of art…
    Sounds to me that those of you who have to squeeze the leaver to the bar initially don’t have enough fluid in the system.
    I bleed them with the free stroke screw all the way out, lever as far from the bar as possible.
    I also bleed them with the disc in rather than the yellow block, as the yellow block pushes the pistons in in my experience.
    This allows you to get as much fluid in the system as possible..

    Push as much fluid up to the lever from the caliper with a syringe as possible and suck back down…don’t empty the reservoir!
    You’ll be surprise how much air is sucked out… Do this visa versa a few times..
    Once you’ve pumped the fluid back up to the lever, squeeze it and release. Repeat until bubbles don’t come out the port. Change the lever angle also while doing this..
    Tap the caples with something to release any trapped air..

    sofaboy73
    Free Member

    I get the same on my rear, which is a mixture of Saint lever and zee calibre, when the pads are starting to wear . However as soon as I swap the pads out all is right again. Looking at the pads taken out they’re not as worn down as I would expect to replace them, but not too far off and as I use cheapo super star pads it’s not an issue

    sharkattack
    Full Member

    The problem is no matter how meticulous you are with your set up and how many hours you spend bleeding and tinkering, you get them all fitted and they do exactly the same. Some sets work and some don’t.

    4 sets of Shimano brakes in this house (now reduced to 3). Years of experience as a bike shop and home mechanic. Absolutely certain at this point that my Saints are just a dud set. I wish I’d sent them straight back instead of assuming it was a set up problem and faffing with them after every ride.

    legend
    Free Member

    Goldigger,

    It’s not as simple as that, and there is a chance that some of the people here have some idea how to bleed them properly.

    Here I have XTs, SLXs and Zees. The XTs are absolutely spot on, constant and very easy to bleed (even when cutting corners). The Zees are ok for the most part, back isn’t perfect though and I think the master cylinder is going after around a dozen rides (definitely looks oily around the linkage in the lever). The SLXs are woeful, spent hours bleeding on Friday (expertly to Epic’s instructions to take me out of the equation, no bite point adjust on SLX either remember) and they still aren’t up to much. Have previously had an SLX replaced under warranty for the master cylinder as well.

    It’s almost like the master cylinder itself is introducing air into the system, hence why one more pull of the lever send the air to the reservoir. That can’t be the case without oil coming out of somewhere though

    PolisherMan
    Full Member

    Yep, just the same with my SLX too. They work but that initial lever pump is disconcerting!!

    sharkattack
    Full Member

    And just to prove the point, my SLX’s are mint. By far the best balance or power, reliability and price of any brake I’ve ever had.

    glasgowdan
    Free Member

    Never had this with the 4-5 sets of deore I’ve owned. I’d thoroughly clean around the pistons, make sure it’s all bled properly (with the pistons pumped partially out as mentioned above) and see how that goes.

    colournoise
    Full Member

    Had one set of XTs do this. Another set of XTs and a set of Zees are spot on though.

    Either there are lots of us who can’t consistently set up/bleed Shimano brakes or their QC is definitely a bit iffy…

    sharkattack
    Full Member

    As I said above I spent years working in a bike shop where you spend most of your time bringing absolute turds back from the grave. I’ve laboured over hundreds of sets of disc brakes. There is almost nothing I can’t fix or bodge. I have done literally everything I can think of to make my Saints work and they won’t have it.

    (Just for those people who still think we just need to bleed our faulty brakes properly)

    poah
    Free Member

    no issue with my previous SLX, my current Zee or my son’s SLX either.

    Goldigger
    Free Member

    Legend, i agree its possible there are faulty units leaving the factory..

    If the lever is returning slowly, id also suspect a sticky piston. Alternatively if the hose has been shortened and the cuts not clean, I’ve noticed that the white inner sometimes can block the hole. Possible its blocked/slightly blocked after pushing the barb in..
    Just some ideas…

    legend
    Free Member

    Sorry mate, it’s nothing to do with the lever returning slowly. Lever speed is absolutely fine, it’s the lever coming back to the bar in the first pull that’s the problem. It’s very Avid-esque except that it’s predictable

    ndthornton
    Free Member

    Could the calliper seal be too springy?…pulling the piston too far back from the disc each time you release the lever? But maybe 2 quick pulls of the lever in succession introduce more fluid from the reservoir which allows the brake to bite on the second attempt. Then the extra fluid is pushed back to the reservoir by the force of the returning seal when the lever is released.

    This could be crap but the behaviour is so predictable it must be possible to work out what is going on

    Poopscoop
    Full Member

    Sorry guys but this has to be done.

    “Just bin them and put on some Guides, job done.”

    😉

    legend
    Free Member

    ahahahahahahahahaha!

    Never has “replace with Avids” been a valid solution to any problem

    Poopscoop
    Full Member

    legend – Member

    ahahahahahahahahaha!

    Never has “replace with Avids” been a valid solution to any problem

    Not even world poverty? 😉

    notsospeedydaz
    Free Member

    My Shimano brakes didn’t like my old avid rotors. No amount of bleeding could get a constant feel changed to superstar disks things got much better

    mikewsmith
    Free Member

    One set do, the others don’t. My m4’s need a little work otherwise they would be back on.
    Bled by me and a couple of times in the LBS properly. Just got used to the double pull these days. As much as you expect from cheap brakes, I think a lot gets overlooked due to the price.

    slackalice
    Free Member

    Personally, I’ve not experienced this issue (yet) with either my XT (3 years) or Deore (2 years old), however whilst reading the experiences above, my initial thought was air in the system either being drawn in through a defective seal, or insufficient fluid from the get go.

    Given the pedigree of some of the posters above, lets discount the insufficient fluid and also the patience aspect of bleeding. The former, given there was a completely filled system to start with, would mean that fluid has to escape to accommodate space for the air, in which case a leak would have be present and identifiable. IIRC, most cases above suggest there are no identifiable leaks, which then leaves the potential of contaminated fluid as being a reason for air present in an otherwise fully filled and sealed system.

    I’m no expert on mineral fluids but the immediate questions that spring to mind are how old is the Shimano fluid that is being used? Does the Shimano fluid absorb moisture ( in the same way as say normal DOT spec brake fluid does) over time? Was there a faulty batch of fluid? Are there alternative grades of mineral oil that can be used?

    Apologies if these questions have been asked before, but fresh pair of eyes and all that.

    peter1979
    Free Member

    I just replaced a rear xt with the exact fault as people describe above. I gave up constantly trying to bleed then finding after a few pulls the lever would go to the bar again. The mechanic at fod couldn’t figure out what was wrong either. I just bought a new rear and will see how that goes.
    Last year I blew a seal on the caliper of a rear slx. That was more obvious though as oil was leaking from it visibly.
    Shimano brakes when working seem great, but they have serious reliability issues.
    I wonder if the new models are any better?

    legend
    Free Member

    I’m no expert on mineral fluids but the immediate questions that spring to mind are how old is the Shimano fluid that is being used?

    Everything from brand new, to quite old. Makes naff all difference. Can use the same fluid in the XTs with no issue

    kayak23
    Full Member

    Does the Shimano fluid absorb moisture ( in the same way as say normal DOT spec brake fluid does) over time?

    No. Mineral fluid doesn’t.
    I have similar issues with my rear XT m785 and usually I get a rock solid bleed with my usual technique.
    Given up with it now and perhaps mistakenly bought a new XT m8000.

    butterbean
    Free Member

    Also experienced this, with a couple of sets of XTR trails. Both were warrantied, one came back fine, and are on my wife’s junk bike now, the other set got warrantied again, for the same issue, then sold.

    It’s a more common issue than I think people realise, Google Shimano Inconsistent lever feel, there are lots of other bike forums, with lots of other people complaining. I had a Madison Tech guy at a race try & ‘blame’ it on a non Shimano rotor a few years ago, which was bolleaux, so I went & put the spare wheelset on, with Shimano rotors & took it back.

    I replaced mine with some Race E4’s – which work, every time I pull the lever. Not nice when racing & wondering if your brakes will work when you pull the lever. Reminds me of my old Fomula’s 🙂

    gonzy
    Free Member

    not had a problem with my zee/slx setup. mate has an slx setup that did this until we bled them 3 or 4 times on the trot…now they work fine

    ScottChegg
    Free Member

    My Zee’s are working fine, but when I changed the pads over Xmas I gave them a quick bleed.

    The oil was black and very viscous, after about 6 months riding. I obviosuly need to take into account the shelf life of mineral oil.

    JackHammer
    Full Member

    I have/had this on a rear OEM deore. I bled the brake a handful of times using different methods and brands of oil, never felt as good as the front and suffered the pumping up problem. Tried cleaning the caliper to within an inch of its life, but I also had a sticky/onesided piston problem.

    I replaced the lever thinking it was maybe a seal in there allowing fluid passed, with a after market deore lever and bled again this time with shimano fluid (from epic, if that’s actually shimano fluid?), flushing the system until I was sure I’d cleared out all the old crap fluid and black stuff. This helped a bit, although the second pump of the lever still bit a bit further from the bar, but not as much as before.

    I then took the caliper to bits and popped the pistons out. I found in the side where I was getting piston stiction the seal was rolled/twisted in its seating so reseated it properly (although this may have happened when taking them out). With the caliper in bits I gave everything a good clean and then lube up with brake fluid.

    Bolted it all back together, bled it, centered it and the lever-feel of the rear brake was now almost as good as the front. I’m going to suggest that the slight difference in feel now equates to the wear on the pads and rotor on the rear which is fairly heavy compared to front’s wear.

    Anyway seems like a PITA and I haven’t taken the bike out on the trails yet… so it’ll probably break again the first time I take it out.

    What frustrates me is that shimano don’t seem to be addressing the issue, which is obviously a big one as so many people are suffering the same/similar issues. They just bring out the same brake with a different graphic or a chromed top cap…

    As it’s the rear one on my bike and I know I’m guilty of rear brake bias and dragging when it gets steep and scary, I reckon it’s probably related to heat build up. Although I could speculate for hours on what exactly is going on I have no knowledge of fluid dynamics, heat transfer and/or metal expansion, so I wont.

    Hope that helps.

    sharkattack
    Full Member

    I just emailed Madison and asked very politely if there’s any way I can fix my brakes. I also asked if they were aware of this very widespread problem.

    How badly will they blow me off?

    My Saints cost a bloody fortune as well. In a misguided attempt to support my local bike shop I paid full retail. I turned up when the boss was there to look over my mates shoulder and couldn’t get any wriggle room on the price. Lesson learned.

Viewing 40 posts - 1 through 40 (of 175 total)

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