Shimano Deore M6000 brakes first impressions & weight

I will keep you updated on how these perform, and if I destroy them or not.

Make sure to apply Loctite to the threads for the reach adjustment, the lever will come out of adjustment quite fast without doing so.

I noticed the paint on the bleed screw was wearing off after on the first ride.

Tesa Grip Tape as brake lever grip after few weeks

I installed Tesa Anti Slip Tape on all controls including the brake levers, no more slippery brake levers.


A closer look:

e13 Dropper post remote 17J V10SS;
Tesa anti slip tape on XTR M9000 shifter

I replaced the Stock Resin pads with Shimano ICE-TECH J04C metallic pads, for longevity and stopping power.


Shimano M6000 Original Resin standard pads,, Uncut 1700mm hose
Shimano M6000 finned metal pads, Uncut 1700mm hose


The narrower clamp allows closer shifter placement, which is what I was looking for. I ran a TRP Spyke lever for months but it did not allow me the perfect shifter position, so I had to choose best brake leverage or better shifting ergonomics, but with Shimano M6000 I don’t have to choose.

  • Ergonomic lever blade, they got it right. it’s better than the TRP Spyke & M930 levers.
  • I like the light lever feel, there is enough lever trow so it’s easy to control the braking with minimal fatigue, I can’t feel any friction or play in the lever.
  • You can use XTR finned pads.
  • The reach adjustment is easier to access than the previous model (M615).
  • Minimal play in the lever, there is maybe 1 mm play or less.



  • The brake levers body have some play, it rocks in and outwards, when I apply the brakes, I am sure the plastic ispec placeholders contribute to this, also there is no extra support, this makes the brake. Less firm feeling, and compromises the braking performance, because if the lever is pivoting like this, the lever moves inwards,the brakes are feeling less powerful.
  • The brake lacks proper adjustment, the reach adjustment just moves the lever in or out, what this means is kids can’t use this brake, but this brake is most suitable for people between medium to large fingers.
  • The housing kinks easily, but I haven’t kinked it but it’s the same as on older brakes so not most robust hose.

  • The housing scratches very easily, after installing zip ties and removing zip ties I noticed the hose was quite scratched up.
  • Seems like Shimano used faulty seals, or bad seals, one rear brake lasted few months, another lasted few rides, then front brake leaked, swapped it, and installed a fresh set, and it leaked after few short rides, caliper was covered with mineral oil. and of course I overheated the rotor, glazed the pads and rotor. Also quality control is not great if this happens, to so many brakes, I doubt they test every single brake before they go into the box,each brake has to be tested, and high quality seals must be used. I don’t know which seals shimano uses on these brakes.
  • I’ve experienced issues with gravel wearing out the pads, bending the pads under hard braking. I also managed to damage a piston.
Bent Shimano J04C Metal pads _20181106_123214
Bent Shimano J04C Metal pads _20181106_123038_0Edit
Brake hose damage_3251
BRake line damage_3665
  • Play in the hinge causing the lever to rock back and forths the handlebar.
    The plastic cover is concerning, it’s not so exposed as other components.
  • The rear brakes i got had too little fluid, so the pads were too far from the rotor, I installed one rear brake first, and and it felt wrong, I tried another brake, and same problem but it was slightly firmer, I haven’t tried all of the brakes I got, but I will have to fill them with more fluid.

March & April 2019

I had issues with air in the system and spongy lever feel, and inconsistent braking power, I cleaned the rotor, pads, sanded them, the brake were bled to perfection, I rode and the air bubble came back, the same feeling, the inconsistent braking power, and spongy feeling, and pads getting glazed.

I think this is due to worn seals, causing leaks contaminating the pads, letting air in.

Seals wear out, and need to be changed, that’s normal, but they don’t come with spares, and you cna’t buy spares, so you have to contact Shimano to get spares I think, unless they will send you a new brake.

Work in progress:

Shimano M6000 leak
Shimano M6000 leak

Shimano M6000 leak, first brake was leaking in the calipers, and this one after few months leaks near the olive, hose.

New bench

So I cut the hose and installed new olive, but it was still leaking.

and the calipers were leaking, I was sure at this time they were actually leaking, completely soaked in mineral oil.

BRake pads

here you can see the aftermath of leaking pistons

BRake pads

you might not notice it but the backside of the pads are completely covered in mineral oil.

Leaking Shimano M6000
Leaking Shimano M6000
Leaking Shimano M6000
Leaking Shimano M6000
Leaking Shimano M6000

Leaking brakes

Leaking brakes
caliper,pads were soaked, the piston has chipped.
pads contaminated abusing the rotor, I had to sand the rotors, install new brakes, with fresh pads and sanded rotors, it works now, but I seem to destroy shimano brakes quite fast, way too easily. I need something that fits me better, need proper reach adjustment that does not affect the actuation/power, which these do, so I had to compromise so I’ve chosen a between spot that is usable, but not perfect, I guess if I had it perfectly adjusted it would not abuse my fingers as much.

Leaking brakes

Because I was sick and feeling so bad a lot I have’t used these brakes as much as I would want to, first brake leaked, so I replaced the rear, but now both leaked, so I had to replace them. I still have working set on the Trek 6300, and one front brake that’s unused. If I get leaking I can swap to those, if it happens on those I am out of working brakes, I need to contact a dealer and try warranty.

Leaking brakes

I will have to send the brakes in for warranty, but I am tired of leaking brakes and these issues, so I might need to stick to mechanical brakes, or upgrade to a better brake, and have spare parts, so I can rebuild it.

Long term review on 3 bikes: Shimano Deore M615 I-Spec-B brake set

.I have used these brakes on 3 bikes, some more than others, until they failed.


  • No banjo fitting
  • The brake lever body/Master cylinder flex when braking harder than 50%,which is why the plastic lid & the separator &  the Master piston unit to bend or get damaged, and cause leaks, so the lever will be soaked in oil, and oil will spit out through the middle where the plastic lid is.I compared the flexing in the levers on m396&m615 and there is significantly more flex in the m615, if you press the lever blade half way you wont see flex on the m396,but on the  m615 you will.
  • Leaking caused by plastic cover bending upwards, and front and the back is also being pushed upwards but sideways too, causing a leak.
    temperature changes, will cause changes to the materials, a minor hit can cause this. the design is clearly flawed.
  • I had to replace one master cylinder due to failed threads, and I had the leaking issues with the new one too.

The threads for the Torx screw failed, which is clamping the cover which clamps down the grommet, SO fluid leaked. but the Torx screw was not damaged. In my opinion these screws are way too small,the design is way too fragile.

  • Impossible so far to get placement seals/grommets/diaphragms, or just the master cylinder separately.

The cause of failure was certainly not over torquing  the screws, It certainly was not a crash that caused it,because I never crashed with this particular brake.



  • Hinged clamp,no need to remove grips & shifter.
  • the levers are easy to bend back if you bent them,which I have done on 2 bikes so far.
  • good modulation
  • good braking power,at least if you use Metal pads
  • it’s not too  expensive
  • it’s not too heavy
  • no need to take off grips to take off the brake, because of the swing arm clamping mechanism.

The Brake Lever will bend if you crash into a tree(before I upgraded the handle bars i was used to ride on the fuel ex 7 with 720 bars),at low-speed,don’t just let the bike fall on the ground,it can bend the brake lever.

  • 23779701854_0a5eeb02bd_b

You can of course bend it back with proper tools and technique.

The I spec B system, is flawed, it’s quite flimsy, the shifter will move if you did not use Threadlocker and torqued it properly,

2016 Shimano Deore XT M8000 Ispec B shifter mounted to Deore M615, (there is no B on the brake but its compatible jsut look for the I spec B holes) i know  the brakes are bit steep in this picture but I have tweaked that later.

The Deore M615 on a 2010 trek 6300

Extra Info

M615 Piston seals: the number written on pistons seals.

IUY 21.1 25  3.19 78 NOK


The Both brakes are too fragile.

Because the brake lever body/master cylinder is way too flexible and that there is a palstic lid,instead of metal lid,which causes the brake to leak.

I have seen a lot of reviews claiming these brakes are a good value at a low price point.

I agree with the braking power for the money is there, but not the reliability, these brakes are too fragile.

same goes for the other brakes with the similar design, for example, M396, M395, but at least it’s possible to get Reservoir Lid Unit for M396, M395.

Failed tHreads on M396 right lever/rear lever.

Flickr album