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  • Shimano’s VariableBitePoint®️ brakes
  • thols2
    Free Member

    basically a brake that causes this much hassle bleeding, is a bad brake.

    To butcher the old adage; powerful, light, simple, pick any two. The higher end Shimano brakes are expected to be light and powerful. The Servo-Wave levers help with this by increasing the leverage ratio after the dead throw is taken up. Problem is, this magnifies the problem of any air in the system.

    Trying to miniaturize the levers and calipers probably also resulted in the transfer ports not being optimized for bleeding. Thing is, they aren’t impossible to bleed, they are just a bit tricky and need some care. As long as trained mechanics can successfully bleed them, Shimano have made an acceptable product. It’s not possible for companies to guarantee that their products are completely user-serviceable.

    On top of that, Shimano have made millions of sets of brakes over the years. It’s inevitable that there will be a lot of users with problems if you sell huge volumes of any product. The users who don’t have any issues don’t post about it on web forums so it’s impossible to judge the proportion of users that have experienced problems.

    mashr
    Full Member

    As long as trained mechanics can successfully bleed them, Shimano have made an acceptable product.

    So we’re all agreeing they aren’t acceptable then when new bikes come with crap bleeds along with brakes that have been bled in the factory?

    chakaping
    Free Member

    The users who don’t have any issues don’t post about it on web forums

    Erm, didn’t you notice that about 50% of the comments on here seem to be “they work fine for me, you must be doing it wrong”?

    devash
    Free Member

    I had this on the rear XT brake of a new bike back in 2017. Did a regular bleed, it went away, rode that bike hard for four years and it never came back.

    sharkattack
    Full Member

    I had this on the rear XT brake of a new bike back in 2017. Did a regular bleed, it went away, rode that bike hard for four years and it never came back.

    So you didn’t have the problem then did you? Your brake needed bleeding, you bled it, then it worked. Easy. That’s not what people are complaining about. There are Shimano brakes out there which can not be made to work acceptably for any length of time no matter how much you bleed them.

    I swear the most annoying thing about this saga is that people who have never experienced it still don’t believe it’s a problem and are willing to write everyone off as idiots who don’t know how to bleed a brake.

    And as for being a ‘trained mechanic’, well I’ve spent more years working in workshops and bleeding brakes than most people on here. I’ve put dozens of hours into problematic Shimano brakes and I’ve also sold stacks upon stacks of Tektro brakes to people who just needed their entry level bike to work reliably.

    thols2
    Free Member

    Erm, didn’t you notice that about 50% of the comments on here seem to be “they work fine for me, you must be doing it wrong”?

    I’ve never seen a thread titled, “I bought Shimano brakes and they just work as advertised,” yet that is many users’ experience.

    I swear the most annoying thing about this saga is that people who have never experienced it still don’t believe it’s a problem and are willing to write everyone off as idiots who don’t know how to bleed a brake.

    I’ve had the problem. I bought some second-hand Shimano brakes, they worked fine when I fitted them but got all weird when I laid the bike on its side, but would then magically start working properly again after a bit of riding. I figured it must be an air bubble in the reservoir so I gave them a bleed to ensure they were properly full of fluid and had no air, they’ve been faultless since.

    The wandering bite point problem is caused by not having them filled properly. If you bleed them properly and make sure the reservoir is full and doesn’t have any air in it, you will fix the problem.

    montgomery
    Full Member

    Five year old XT, four year old SLX – no problems here! Bleed them once a year or so. Had the issue once after replacing the rear SLX hose and refilling with a Marshy bleed. Did the refill again caliper up with an Epicbleeds kit, sorted (over two years ago).

    onewheelgood
    Full Member

    Me too 🤔

    +1. Most of my disc braked bikes have been Shimano, currently have 4 bikes hung on the wall with Shimano discs, never had the problem at all. Had a horrible experience with Elixirs, and more recently with Guide sticky pistons, so Shimano definitely winning for me and that’s before you consider the safety of the finish on your inconsequential workshop furniture.

    mashr
    Full Member

    I’ve had the problem. I bought some second-hand Shimano brakes, they worked fine when I fitted them but got all weird when I laid the bike on its side, but would then magically start working properly again after a bit of riding. I figured it must be an air bubble in the reservoir so I gave them a bleed to ensure they were properly full of fluid and had no air, they’ve been faultless since.

    So you haven’t had the problem then. You had a brake that needed a bleed.

    The wandering bite point doesn’t magically fix itself mid-ride, it can change (for better or worse) many times a run.

    FWIW I found Elixirs easy to work on, and you dont tend to find many people saying that

    5lab
    Full Member

    I’ve had it with some shimano brakes, not with others. Some reports suggest its either down to the viscosity of the oil in lower temperatures (which could explain why some people don’t get it), or slight engineering faults in the master cylender allowing a small amount of air in.

    stingmered
    Full Member

    Intersection

    stingmered
    Full Member

    Check

    stingmered
    Full Member

    I give up trying to post an image…
    Used to work!

    philstone
    Free Member

    Image..?

    Fixed it for you..

    Nope, looks like the websites broken.. Again.

    Linky

    scotroutes
    Full Member

    Let me help you with that…

    Is there another set required of “Those who can’t post images”?

    magoos_mate
    Free Member

    I find it very curios that the engineering giant that is shimano haven’t managed to find the root cause of the VBP condition and instead persist with the same basic design year after year after year 🤔

    Unless of course… User error 🧐

    LAT
    Full Member

    The wandering bite point problem is caused by not having them filled properly. If you bleed them properly and make sure the reservoir is full and doesn’t have any air in it, you will fix the problem.

    folk with the problem are saying that with some sets of brakes this can’t be achieved.

    i’ve experienced WBP. a bleed fixed the issue, but i do find the xt levers harder to bleed than the 501 non series

    mashr
    Full Member

    Unless of course… User error 🧐

    But then remember you’ve got to include Shimano themselves in there as they send them out the door with the issue already happening

    sillyoldman
    Full Member

    Brakes of all brands benefit from a bleed from new.

    When I worked in a shop, the Sram tech guy advised draining Avid (yes – a while ago) brake’s fluid and replacing with better brake fluid from new, so a bit more involved than a bleed.
    As others have said, Servowave in the upper end levers amplifies any poor bleed symptoms, and it’s unsurprising that rears are more often affected given the length of hose and the less vertical route from caliper to lever.

Viewing 19 posts - 41 through 59 (of 59 total)

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