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  • Shimano’s VariableBitePoint®️ brakes
  • qwerty
    Free Member

    I appreciate this has been done to death.

    But a simple yes/no – what happens if you swap either:
    1) the caliper only for Magura/other mineral?
    2) The lever only for Magura/other mineral?

    As a process of elimination, does it resolve the dreaded variable bite point?

    I’m aware that a good bleed should sort the issue, but thats only achievable by the gods and not mere mortals.

    Having put up with it for years, I just rode a bike with base level OEM Tektro brakes and did a huge amount of hard consistent braking downhill & they were consistent at all times. Yesterday I got back on my Shimano MTB and it felt awful.

    So, yes or no?

    weeksy
    Full Member

    I’m always baffled by this as i’ve never ever experienced it, despite having owned dozens of sets of Shimanos in the last 20 years.

    scotroutes
    Full Member

    You and I are amongst the gods @weeksy.

    thols2
    Free Member

    I’ve experienced it, but a thorough bleed and ensuring there is no air in the master cylinder reservoir fixed it.

    dc1988
    Full Member

    I’ve also never experienced it, I’m assuming it doesn’t affect power but will the bite point move enough for the lever to hit the bar?

    BenjiM
    Full Member

    I have one that does it and one that doesn’t, on the same bike. It’s a bit annoying and I’ve put up with it for the last 7 years. Might put something else on it 1 day when I’ve got some spare cash!


    @dc1988
    that’s pretty much it, yes.

    fazzini
    Full Member

    You and I are amongst the gods @weeksy.

    Never experienced it here either @scotroutes, but maybe it’s because we (obviously just me) are not among the cycling gods that we haven’t experienced it 😋

    smokey_jo
    Full Member

    I’ve had it on both of my shimano sets and found it was much worse if you used one of those hanging storage hooks. Also appeared more frequently if bike transported on it’s side in the boot more than 20 mins.

    scotroutes
    Full Member

    Both indicators of air in the system.

    Rubber_Buccaneer
    Full Member

    You and I are amongst the gods @weeksy.

    I’m not amongst the gods but I do follow the whole laborious tappity tap on the brake lines, flickety flick of the lever for however long the gods deem appropriate before I am blessed with no more air bubbles in the bleeding cup of truth.

    julians
    Free Member

    had the variable bite point once after a bleed, bled them again properly and the brake was back to normal.

    Yak
    Full Member

    I did 1 and 2 combined to be sure. Fixed the problem. 😉

    chakaping
    Free Member

    I assume you’ve done a bleed using a syringe to push fluid up from the caliper to the funnel at the lever OP? And moved the lever in and out while squeezing to get extra bits of air out?

    If that hassn’t worked, you’ve got a lemon – and personally I’d replace it with a different Shimano unit.

    I honestly haven’t had the VBP for years and my MTBs are all Shimano.

    Also, I don’t know if this is still the case – but it used to seem that the more basic Shimano units (Deore, Zee) might get VBR less often than the SLX and XT.

    rickmeister
    Full Member

    Do you have to do a full bleed?

    Pop the wheel off, push the pistons in and then remount and apply the brakes to re-set everything. Pushes any air at the top back into the m/c… has worked for me with Hope and SRAM. Plus, not storing bikes vertically or on their sides.

    thols2
    Free Member

    I’ve had it on both of my shimano sets and found it was much worse if you used one of those hanging storage hooks. Also appeared more frequently if bike transported on it’s side in the boot more than 20 mins.

    Symptom of air in the master cylinder reservoir. They need to be bled properly so the reservoir is full of fluid, without any air.

    lardman
    Free Member

    It’s definitely a well/badly bled issue.
    However, the same process of bleeding has given me both perfect, and squidgy brakes at different times.

    I have resorted to using the technique I saw Steve Peats mechanic use, which is a complete fluid drain from the lower calliper end, then pump new oil back up through to reservoir screwed into bleed port of master cylinder. Any bubbles are forced out the top and brakes become solid again.

    Wastes quite a bit of fluid, but works.

    Across the 10 bikes in our house, all with shimano brakes, I’ve done quite a lot of bleeding. Some have never needed it, some need it a lot.

    Also, the bikes that get used a lot, never get the seal ‘microleak’ issue, as the seals stay well oiled. The ones that get used infrequently, ALWAYS get it after a year or so.

    I plan to try a ‘Shigura’ setup soon to see if they’re as good as people suggest.

    teethgrinder
    Full Member

    Hope E4 caliper with RX4 mineral oil seals, and shimano lever is an option.

    chakaping
    Free Member

    Also, the bikes that get used a lot, never get the seal ‘microleak’ issue, as the seals stay well oiled. The ones that get used infrequently, ALWAYS get it after a year or so.

    I just came across my first set of leaky Shimano calipers in some Tiagras on a secondhand bike, there might be something in your theory about regular use.

    I plan to try a ‘Shigura’ setup soon to see if they’re as good as people suggest.

    I had a quick go on my friend’s Shigura’s – they were by some margin the most abruptly powerful (aka grabby) brakes I’ve ever used.

    He loves the feel, I much prefer the standard Shimano feel. I wonder if they’re all like that though.

    thols2
    Free Member

    Hope E4 caliper with RX4 mineral oil seals, and shimano lever is an option.

    The Shimano levers are the source of the variable bite point. They are slightly tricky to bleed, plus the ServoWave mechanism magnifies the effect of air in the system.

    lesgrandepotato
    Full Member

    A good bleed is not hard. Get the fill cup and watch the you tube video.

    Crack on and it’ll only take you and hour or so.

    HobNob
    Free Member

    Bought a bike with a set of Saints on it, first Shimano brakes I’ve had in years. In a shocking turn of events, both have standard Shimano VBP 😆

    Bled them, after scouring the internet on the various ‘insider’ ways to get the perfect bleed, bled them again, and again & generally wasted many hours of time trying to get them right. Might as well have resorted to voodoo dances & rituals 🙄

    Gave up, fitted my spare Code RSC’s, for which I had to even split the hose due to stupid internal routing, put it back together, gave the lever a squeeze & it was rock solid. No more worrying about brakes.

    scotroutes
    Full Member

    Bled them, after scouring the internet on the various ‘insider’ ways to get the perfect bleed

    Bleed instructions are on the Shimano website.

    sharkattack
    Full Member

    A good bleed is not hard. Get the fill cup and watch the you tube video.

    Crack on and it’ll only take you and hour or so.

    The words of a none believer. I envy the fact you’ve never dealt with a duff set of Shimano brakes.

    Bought a bike with a set of Saints on it, first Shimano brakes I’ve had in years. In a shocking turn of events, both have standard Shimano VBP 😆

    My first experience on it was with Saints. Fitted to a DH bike and taken straight to the Alps. I spent every night bleeding the bastards, wondering what I was doing wrong. This was nearly 10 years ago and the breaks are still the same and people are having the same issues.

    jwh
    Free Member

    I have had the wandering bite poiunt on a few sets.

    I found the technique used in this video worked the best

    mrpaul
    Free Member

    Seen Marshy’s bleed technique posted on here a while back and gave it a try. Works for me:

    mrpaul
    Free Member

    Ha! Great minds etc…

    steve_b77
    Free Member

    I’m aware that a good bleed should sort the issue, but that’s only achievable by the gods and not mere mortals.

    No it’s not, I was going to quote the above easy bleed, but it’s been done 😀 literally takes 30minutes tops to do a bike like that, even if you’re not exactly mechanically minded.

    I’ve had Shimano brakes for over 10 years from non-series long lever thingies to XTR M9100 and also GRX and Ultegra hydraulics and never had this. Then again I generally use shimano rotors and OE pads, I did use UberBike Race Matrix for a while, but they went downhill in feel and power and switched back to Shimano Resins on everything.

    kayak23
    Full Member

    I’m always baffled by this as i’ve never ever experienced it, despite having owned dozens of sets of Shimanos in the last 20 years.

    Me too 🤔

    mashr
    Full Member

    No it’s not, I was going to quote the above easy bleed, but it’s been done 😀 literally takes 30minutes tops to do a bike like that, even if you’re not exactly mechanically minded.

    Or it doesn’t, which is the big problem here. Bleeding should consistently be a doddle and shouldn’t be that mess of a process where you’re letting oil piss out of the bleed hole (not even using the nipple). I’ve warrantied Shimanos for this, I’ve also had brand new brakes suffering from VBP and most recently I’ve swapped by TRP levers for XTs. One is fine the other is being an absolute **** to sort out (tbf not varying in Shimano style, just not bleeding nicely) even after using the Marshy method. By contrast, when the setup was full TRP, you would’ve had to have gone out of your way to bleed them badly.

    scotroutes
    Full Member

    shouldn’t be that mess of a process where you’re letting oil piss out of the bleed hole

    Why on earth would you want to do that?

    Rubber_Buccaneer
    Full Member

    Bleeding should consistently be a doddle

    This is what it boils down to in my opinion. This Shimano problem is so widely reported that I think they should already have looked at why and sorted it.

    Rubber_Buccaneer
    Full Member

    Why on earth would you want to do that?

    It’s the method employed in the Marshy video above. Marshy is probably responsible for the scarcity of Shimano brake fluid a year or so ago

    scotroutes
    Full Member

    😂

    thols2
    Free Member

    The way I bleed them is to screw the funnel into the master cylinder and put fluid in that, then connect a syringe to the caliper and draw fluid out until the syringe is full, then reverse the direction and use the syringe to force the fluid back through the system. Then close the bleeder and you should have a good solid lever. Then repeatedly squeeze and release the lever to get any remaining air bubbles out of the reservoir. It’s a good idea to adjust the lever position a bit to make sure the bubbles can float up to the transfer port and up into the funnel. It does not waste fluid and seems to work fine. Key thing is to make sure you have all the air out of the reservoir.

    Onzadog
    Free Member

    I use two syringes, one attached either end. Start by pushing fluid in the caliper until it’s coming out clean at the lever. If it’s really manky, this is where you might want to empty the top syringe and half fill with clean fluid.

    Tie the lever off and then squeeze and suck at the caliper to remove all air from the caliper.

    Release the lever and push fluid in at the caliper to push air out of the lines into the reservoir. Tie the lever off, remove caliper syringe and refit bleed nipple.

    Release the lever and now push and suck the lever syringe to remove any air from the master cylinder reservoir.

    It’s quick and clean while using minimal fluid. You just need to think about what you’re trying to achieve.

    tall_martin
    Full Member

    I solved this by buying a set of hope e4 and v4.

    The Shimano brakes have been shunted on a bike that gets ridden with my 3 year old sitting on it.

    Not braking very much and never braking hard has solved the problem.

    The hopes haven’t been problem free, but they haven’t suddenly and alarming had a different and unexpected amount of power for a given squeeze.

    missions
    Free Member

    QWERTY before you go and spend big on new Magura parts could I recommend you try Putoline 2.5 shock oil. It is also mineral oil but slightly thinner than the Shimano variant. This allows the air trapped to be purged easier from the system. Cost of a 1lt bottle around £10
    Been running this in my Shimano XT and Saints for over a year both locally and on a trip to the Alps with zero problems and with zero bite point issues.

    zerocool
    Full Member

    I agree that a bleed should be simple and easily repeatable by 5he average home mechanic. I’ve had lots of Shimano brakes over the years (Deore, XT, SLX, Saint and Zee) and they’ve nearly all suffered from it at one point or another. You shouldn’t have to buy special expensive after market fluid or spend an hour to bleed them.

    branes
    Full Member

    I’m going to have to plant my flag in the baffled camp here. Yes, I sometimes have to give my brakes a pump after they’ve been stored vertically, but even the cheaty ‘bleed’ where I just add some fluid at the lever and give everything a tap and a pump has always worked well for me, MTB or road, MTB being easier. It’s fundamentally pretty simple – push fluid at the lever which pushed the piston at the other end – only air in the system or a pretty big leak can affect this badly.

    Swings and roundabouts – I’ve recently started using SRAM, which does seem to be more solid six months after my initial bleed, but I did manage to peel some paint off an inconsequential workshop stool doing that (more complex) bleed!

    Northwind
    Full Member

    lardman
    Free Member

    It’s definitely a well/badly bled issue.

    I reckon it is. But, like with some other brakes, the amount of problems people have is ridiculous and definitely a problem with the brake. Bleeding is 100% a solved problem, it shouldn’t be hard at all. Maybe if it was a side effect of some peformance-adding bit of design that’d be OK, but it doesn’t seem to be. So basically a brake that causes this much hassle bleeding, is a bad brake.

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