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Shimano Disc Brakes – How-To Shorten Hoses or Quick Bleed


Hi everyone! A question that I got quite a
few times was how to shorten Shimano brake hoses when installing new brakes so here is how it’s done. This is a set of Deore XT M8000 brakes but this procedure can be used on any current Shimano brakes. The few tools needed are a vise grip,
you need an X-acto knife with a good blade you need an 8 mm wrench, a piece of wood, a hammer and then a couple of pieces that will come with the new brake set. The yellow blocks are used to clamp on to the brake hose Then you have the olive and the insert, I will show you how to use them later These are specific to the type of brake hose you have. BH90 is the most current one. The bleeding tool from Shimano is noting more than a funnel and finally you’re gonna need some Shimano hydraulic mineral oil You can buy this in smaller containers as well If the brake hose is externally routed on your bike just go ahead and install the caliper, then run it nicely using the posts provided all the way up to the handlebar where you will be ready to start trimming it to
the appropriate length. For a bike like this that has the brake hose internal to the frame I’m gonna have to trim that hose right now before I can even route it correctly You will try to create a 90 degree angle here so try to cut it as straight as you can. And you just push down on the blade…done. Having the hose routed through the frame all the way up still gives me plenty of slack here at the head tube. The 1 meter long hose of the front brake is plenty whether you install it moto-style like you see it here or whether you install your front
brake on the left hand side. The routing of of this hose is very simple you just go through that clip and then to the inside of the lower leg of the fork. You don’t need the grips here I just pushed them in temporarily to give me an idea of where I’m gonna want to have the lever. These are designed for one finger breaking so I usually install them about half an inch in from the end of the grip. Just like this. Next were disconnect this brake hose from the master cylinder so what I’m going to do is just angle my lever about 45 degrees up because this is
filled with oil and once I disconnect the hose I don’t want that oil to start leaking from it. What’s called the connecting nut is protected by this rubber boot cover so slide this off and then That’s the connecting nut, you’re
gonna need the 8 mm open wrench This is normal thread so righty tighty
lefty loosey. It was really tight. and…just undo it. Just slide this down onto the hose
you’re gonna need it later. Pull on the hose it’s gonna come out. Time to figure out how much hose you need. Front brake is fairly easy because you have two fixed points One is here this clip on the fork the other one is your master cylinder. This is going to flex as the suspension compresses however this is the worst case scenario with the fork fully extended so if you measure it to the shortest length that you want right now you’ll be fine. I usually leave something like this Is going to be right here under the
handlebar. If you’re unsure make sure you measure this a few times. Needless to say once you cut it is cut you can’t have it back. This is where I use this piece of wood again and I usually put it right on top of the stem. I have my hose marked right here. Next you’re going to grab the olive and just slide it over the hose The insert goes right in the
middle of the hose here but you have to push it in all the way. And this is where
you’re gonna use that yellow block with the vise grips and the insert is already
right there in the middle. Take the hammer and just pound it. Once you’re done you want it to be flush to the top of the hose. So nicely lined up right now: insert, olive, connecting bolt and the rubber cover. Shimano recommends
to put a tiny bit of grease right here on the outside of the olive and the
threat of this bolt. Grab the 8 mm wrench and as you’re pushing on the hose you’re gonna start to tighten this up. Keep pressure on to the hose. This is 5-6 Nm so it’s not a whole lot Don’t go crazy on this one. Last thing to do just push that rubber cover back on. For the rear brake I have to measure the hose as well Also remember if you have
any port covers you have to install those first. So the worst case scenario
in this situation would be With the handlebar twisted something like that. So make sure you have a little bit of slack at that extreme. It is not as bad when you’re turning to handlebars the other direction And then trim it and install
it just like I showed you for the front brake. If you’re switching hoses at this
time, that is from left to right it’s even more important to have your brake levers angled up like this because at some point you’re going to have both hoses disconnected so you want to prevent oil from leaking out of those
master cylinders as much as you can. Rest of the procedure it’s exactly the same. For this next step start with the lever kind of parallel to the ground and that is one of the bleeding ports of your brake system the second one it’s right here on the caliper, It is the one covered with that little rubber cap. Enemy of any brake system is air trapped inside and this is
no different. And if you think about what we’ve done we’ve definitely introduced a
little bit of air here by disconnecting the hoses. And that air is
now trapped in there and it’s going to prevent your brakes from working
properly. With the bike on the stand remove the wheel and replace the pads
with this bleeding spacer or bleeding block. Just use that same pad pin to hold
it in place. You’re most probably gonna have to loosen up those caliper bolts
because the bleeding block feeds in from the opposite side, there it goes. You might be tempted not to install the bleeding block when you’re just shortening hoses, but I would strongly recommend you do. otherwise you’re gonna
overfill the system with fluid. With the lever somewhat horizontal use a 2.5 mm Hex to remove that top bleeding port. As you take that out make
sure you remove that tiny o-ring as well. Tiny o-ring that you’re gonna find here
at the bottom of the funnel as well. The funnel screws in pretty much where
you took that screw out. Just snug. and stop. You’re going to remove this oil
stop as well you don’t need it now. Pour some oil into the funnel maybe about half of it and start pumping your brake lever. As you do that you’re gonna see air bubbles coming out If you were a bit afraid and
didn’t tighten up this connecting bolt enough before as you start pumping your
lever here it’s gonna start leaking so just tighten it up a little bit more. Next you might want to just take your wrench or your screwdriver and just do a little bit of this. You’re trying to encourage those little bubbles to come up to the top where by pumping your lever you’re gonna get all the air out. Loosen up the lever on the handlebar and and just go… see, I just angled it a little
bit and there was a bit more air coming out Do the same with the lever angled
about 30 degrees the other way. Use that oil stopper just to plug the bottom of the funnel and now you can undo it without having all that oil pouring out. As you take out the funnel make sure it comes out with that little o-ring because next you’re gonna replace that top bleed screw that has it’s own o-ring. Tighten it to about 2 Nm so that’s not a lot. Spray a little bit of Isopropyl alcohol
and wipe that lever clean. I have an older video
talking about when and how to replace the brake pads. Repeat the same procedure
for your rear brake and go out and make sure you do a proper break-in of your
brake system especially if it is a brand new one. A brake system with no air
in it will give you that solid feel at the lever that would never allow the
lever to go all the way down to the handlebar. A full system bleed requires
a couple more steps but 99% of the time if you’re just shortening hoses this is all you need And that is pretty much the end of my video folks. If you have questions let me know in the comments below If you haven’t done so don’t forget to subscribe to my channel and like this video and until next time I will see you on the trails. Cheers guys, Cheers!

34 thoughts on “Shimano Disc Brakes – How-To Shorten Hoses or Quick Bleed

  1. Fantastic video. I just this week converted an old Specialized Hard Rock Pro from cable pull to hydraulic and the hoses are crazy long. I was just going to leave them long but now I know how to shorten them. Much appreciated.

  2. Ok here is one. Take off ur shock, remove the can, now looking at the ifp shaft there is a oring holding a large washer. The bottom out oring. It separated. Why and how and how do you replace that without doing a full ifp service?

  3. Great how to! I would add that you can use a good pair of side cutters or Park cable cutters as well as a knife, and you can use some type of strap, cable tie or even tape to hold the lever closed for an hour or even over night (with the funnel installed & with fluid) to keep the system pressurized and open at the same time. This old trick works surprisingly well and tends to get every last bubble of air out of the system….. Hopefully this vid gets a tons of views because it's the best I've seen on shortening Shimanos.

  4. This is one of the reasons why I prefer Shimano brakes. Everything is simple, I’m doing it on the same way and works perfectly. The only difference is that I’m using a cable cutter for the hose. I used to cut it with knife before but after I tried it with cable cutter I couldn’t be bothered with the knife anymore.

  5. Tnx, great video. I just wonder, wouldn't it be better and safer to push the oil from the caliper into the funnel, just a little bit, to be sure to push those air bubbles into the reservoir? Do they travel into the reservoir by themselves after you connect the hose?

  6. Great job on this tutorial. I very much want to shorten my hoses, and I have the bleed kit and the cutters already. I still need to find the insert and the olive. Do you buy those somewhere? I assume that once the olive is used once, it gets deformed onto the cable end and thus can't be moved or re-used.

  7. The yellow bleeding spacer, does it come with a set of new brakes, or do I have to order one additionally?

  8. hi Love<TB
    what if there's still bubbles inside and we dont know? that will cause the brake uneffective….how to purge that bubble away again? repeat the process with the funnel?

  9. Can i also do this with my wheel installed? So that the brakes will bite into the Rotor instead of the bleeding Block. Just the small bleeding i mean
    Sorry for my Bad English. Answer would be great

  10. What if you don't have the insert and the plunger(Olive) say, you are installing a used brake, how do you get the insert and the plunger(Olive) since you can't reuse the old ones. I will wait. You see, everything isn't always ideal as you demonstrate in video dear content creator, some people like me just can't always afford new brakes that come with everything.
    And again, when you cut the rear brake cable for the bike with the internal routing, why didn't any oil come out? I thought shimano brakes are already filled with oil and also bled. All these information when left out creates nothing but confusion.

  11. I have learned a ton from you man! First you helped me with my 1×11 conversion now you're helping with my mechanical to hydraulic brake conversion. Really appreciate your vids. Very simple, direct and to the point. Thanks!

  12. No need for bleed block for bleeding levers. Bleed block is for bleeding the calipers so you don’t get oil on your pads. It’s nonsense when people say for both so you don’t put too much oil in lines. Countless lever bleeds with caliper on disc, never an issue. Total waste of time.

  13. Shimano XT vs SRAM code R, hello to whoever is interested in
    my experience. I have had XT and currently I’m ridding code R, if I knew what I
    know now I would have replaced the code R directly on my new bike for the XT
    BR-M8020 (or Magura MT7 little bit overkill for me). I have had zero problems
    for 3 years with my XT and now ridding code R for 4 months I’m almost at the
    point of replacing them. So why: They just do not quite functionate as how a
    good set of disc brakes should + pour material quality, rotors rust, cheap
    paint, oversized components, (DIY) unfriendly to work one, never quite the
    result you where hoping for after some tlc and so long. My girlfriend rides SLX
    for over 2 years and are in better condition than my code R, we ride 95% of the
    times together. I hope that I saved some people from wasting their time, money
    and frustration. Something about myself I’m a perfectionist very technical
    skilled and realistic. (Last summer in Austria a DH bike rental place told us they
    replace all Sram brakes directly and sell them for dirt cheap new, they just do
    not want to bother using them. That should have been a motivation for me to
    replace them directly but I did not, regrets big time.)

  14. Great No Nonsense Tutorial using basic tools and techniques, now I know for SURE that all I need to buy is the Olive/Inserts & Fluid. Curious about cable cutters on tubing? Im guessing they crush/deform cable or you would have used them, what about electrical wire stripers? Thanks for Tutorial, the fact that you were not wearing gloves immediately told me your are a real mechanic who's first brake bleed was not on a bicycle 🙂

  15. I have Shimano BR-MT500 brakes and wonder if the yellow bleeding block will fit? If I remember correctly there is different colors (size) like red bleed blocks.

  16. New to hydraulic brakes here. Tomorrow or so, I'll be doing this. I'm just waiting for the bleeding kit to arrive in the mail. LBSs here in Palm Beach County Florida are outrageously expensive so YouTube has been my bike mech school for the past decade.

  17. Can i use slx br7000 straight out of the box without shortening..i see it comes with the brass fitting and tip to be hammered in.is that because if cutting off you lose them and those are replacements.or this process needs done before using..sorry if this is a silly question but i just like reassurance..ty

  18. Hello mate,
    I have recently purchased the new deore xt m8100, the front brake works fine it’s rock solid but no matter what I do to the rear brake it’s just weak as heck, no matter how much bleeding I do, do you have any tips or wisdom? You seemed to be pretty experienced with a variety of shimano brakes.
    Thank you in advance 🙏

    Long story version below lol

    I bought them through a bike shop where he could services my bike, install the brakes and put a new stem cap where the front brake hose could pass through,
    usually it’s something I’d do myself (live overseas and don’t have many tools to change the star nut ) so I chose to get it done through a shop and have the mechanic there do it, ofcourse he had no idea what he was doing I think it was the first time he ever had done hydraulic brakes 😟 but anyway, I took them home and I couldn’t even bed the brakes in because there was so much air in the brake lines I couldn’t get a good enough grip to start. So I bought a bleeding kit which I thought I wouldn’t need for a while. So I bled the brakes and the front one was good and solid but the the back one I tried everything, watched soo many tutorials and read forums and can’t just seem to get them to not feel spongey compared to the front one.
    I still think the front one is spongey but maybe I’m just used to squeezing the life out of a cable actuated brake lol.

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