This is an excellent tutorial, With it I have managed to bleed my grx brakes perfectly and only spilled a little mineral oil on the carpet. Your tutorials have allowed me to complete my very own bike build from scratch! Kudos
Great easy to follow video. I had watched other videos but non of them covered the need to burp the system by moving the bars. Once I did this procedure air bubbles appeared immediately and after a few pumps my front brake was as sharp as the day I purchased it. Thanks 😊
I agree 100%. Bleeding road disc brakes can be fucking frustrating. The explanation and orientation of the fluid reservoir shown in this video is literally the essence to it. And whilst some other videos also tell you to rotate the bike while doing it, none of them explain why and in which angles.
This is a very good instructional video. One of the few that very clearly show all the steps as explained in Shimano's dealer manuals. Once you get the hang of it, as with everything, it's pretty straightforward.
Thanks Calvin, I'm a competent home mechanic but bleeding brakes had always been my achilkes heel. You're video is fantastic and the instructions are really clear and easy to follow. Set up a set of GRX brakes and they're working perfectly. 👌
Great tutorial. My only criticism is that it's fairly formulaic and doesn't focus on some of the "why's" that people may miss. If people are to remember these instructions better, it's much easier to with the help of logic opposed to a check list. That being said, it would make the video a bit longer so I can understand why it has been written a tad shorter.
Why is always good, but when you're frustrated and want a quick how to answer, a quick video is also very helpful. Maybe a separate section at the start or the end on the theory? We wouldn't want theory and rambling in the middle of the steps.
It is a great video, thank you. I'm finding this job much more difficult on the rear brakes because the length of routing of the hose means there are so many places where air pockets can collect.
I watched several clips about this theme and then worked my way through bleeding - but this tutorial was the real helpful one to acheive a truly satisfiying result!
Thanks great awesome guide I'd always just been doing gravity bleeds and I decided to bite the bullet and this really helped get a little bit firmer lever
I want to add a note for anyone adding oil for the first time into an entirely dry setup, as in cases where calipers and the shifter ship separately: make sure there's enough oil in the cup, and you're not going to let gravity draw out additional air in the lines as the video demonstrates, but you'll instead use the syringe to repeatedly draw air out from the bottom, somewhat like SRAM's method for their dual-syringe setup, which here would be great. (Again, assuming an entirely dry system vs a system with oil and a minuscule amount of air.) Keep drawing out the air from the bottom, and repeat, repeat, repeat until the lever feel is firm. Don't overdraw from the cup, so make sure you've got almost an entirely full syringe and start with maybe 1/3 of the top cup.
Thanks for the explanations. Actually I would have expected that, at the end of the operation, the brake lever stroke would have been shorter than shown in the video
Me too! That’s the reason that I was searching how to do a bleed in the first place because my levers nearly touch my handlebars, which I’m not used to coming from mechanical brakes
Long and drawn out like most American video’s, but the only one that suggests reverse bleeding from the reservoir like you would on your car. And that was the clincher, good firm brakes. Just one slight amendment; after pumping through all the air try closing the bleed nipple mid pump a few times. Thank you Mr Park Tool.
Long? Absolutely. Drawn out? Disagree. Everything was very concise, he was just more thorough in his procedure than those that would have you believe it's a 5min task. The reverse bleed and burping steps finally got my brakes feeling factory again.
Hi. At 08:20 you’re starting a step with quick opening/closing of calliper bleed nipple with pumping of brake lever. May I ask what is the reason for that?
Pumping the handle should compress any air bubbles. The smaller the bubble, the less likely it will stick to the system. Then, opening the bleed screw should allow the bubbles to move through the system.
From my understanding: This a technique to “combine” several mini-bubbles to one/two bigger ones. This one bubble can be released why more easily and less fluid will be pushed out when opening the port for a millisecond.
Hello Calvin, thx for this helpful video. When pressuring the handle (video 7:55 min) air bubbles keep coming out of the brake caliper. I had to fill the funnel 3 times. Is this normal? For info: bleedin g the rear brake ST-R8050.
I’m swapping my rear calliper from BR-R7070 to BR-R7170, keeping the same internally routed rear brake hose ... Question: I know I will need to change the olive, but do I need to change the insert as well? Also assuming this swap will likely require a brake bleed after.
Why do you first bleed from the calliper site and then proceed to bleed threw the lever, why not the opposite way? Then one could dispose the old mineral oil in the plastic bag, before bleeding a fresh one from the bottom. Doesn't it make more sense? Otherwise you mix the old mineral oil with a fresh one.
They are following manufacturer's (Shimano) instructions. And since brakes are the most important component I'd say sticking with what people who designed them say is a good idea. You can completely flush from the calliper too, albeit it's a bit more annoying.
The part with quickly opening and closing the bleed nipple is somehow giving me grief. At first it failed to repump completely, so I started from scratch and pushed the fluid up through the caliper again. Quite a lot of bubbles came out, so air somehow got in. But the quick open and close part was still weird. There was definitely fluid in the funnel and in the hose, but after the pressure was lost it was still not possible to repump it. Except, somehow some way it worked - I left it alone and it worked. I thought it was maybe the plunger I put in the funnel, and I repeated it three times just to see which step caused it, but it was mostly random to me. The lever feels firm now, so I decided to leave it alone. But I still wonder. I will see with the second lever.
That's the only way I think. Also, I don't think most bike shops do the tilting, it's probably good enough without the tilts most of the time. You can also do the SRAM way I think, which is pulling oil from below with the syringe. Back and forth a couple of times.
Hi there PT, thanks for the tutorial. As it seems to be way more complicated than on flat bar brake levers (e. g. Shimanos MTB lines), how picky has one to respect these tilting angles? As far as I understand, the various tilting help move any “trapped” air bubbles and fill oil pockets in the hydraulic system. But how exact do you have to be? I in general just do a solid 50 to 100 ml bottom to top flush to just push out all residual air. In 95% of all bleedings in our shop, this is the solution in “the first go”. But if you have the time to comment on this approach, I’d glad to learn sth. new/better. Thank you. And keep up the excellent work.
Calvin, you guys make great tutorials. I've learnt quite a lot from you. However, IMHO, some of the maintenance belongs to the hands of our local bike dealers. Its the routine and skills they have. I'd probably end up with quite a mess at my place. Still, also my compliments to the hobbyists that manage this kind of work. Chapeau! (as they say in France)
Thanks. We feel that not every video we make is for the end user. Professionals also need videos, and special tools. This is one example. Anyone is welcome to purchase the BKM-1 and BKD-1, but our intent was this is a shop product. Just wait till we get to the frame machining tools!
I did a full gravity bleed and the oil came out clean. Immediately afterwards, I syringed fluid up into the lever from the caliper and it was filthy. It seems the gravity bleed didn't fully flush the system. Shimano 105 R7020 (pretty much the same as shown in this video)
Very useful video, thanks. I have the GRX brakes but also with in-line sub levers fitted. What would be different about the process to take these into account?
Wouldn't you want to clean the rear caliper BEFORE installing the bleed nipple cap? In this video it was installed and you can clearly see mineral oil all over the bleed nipple. That could make it's way back to the pads and contaminate them.
In my experience most of these steps simply isn't necessary. All I do for a perfect bleed every time in minutes is attach the funnel and push fluid up using a syringe. I then rotate the bars to various angle -45 degrees to 45 degrees and squeeze the brake lever several times until no more bubbles appear and the lever feels firm. That's it. Done.
why did you put in new liquid from the top when the old was dirty? is that just another way of changing liquid? i would imagine if you kept using the syringe and burping that it would bring the same result. whats the benefit of gravity feeding the new liquid?
The system sometimes “pulls” in some oil if air is released. If there is no oil reservoir above any air in the system, the lever etc. could suck in some air, which gets trapped. If you replace old oil with new one, you will remove any dirt, that could damage the rubber o- or quad-rings. Is used “old” oil in the past, if I had to bleed “in the field” and everything was fine. But if you gave the chance to refill with new one - do it. Hydraulic systems on bikes are not “hermetically sealed”, so you will always loose tiny amounts of oil. And you will always collect some dirt resulting from wear&tear inside the system (moving rubber on metal + dust from outside).
Adding anything to the manufacturer's fluid would change the properties, and they certainly would consider that voiding the warranty. Being patient and thorough is the best way to remove bubbles.
@@parktool Warming a fluid isn't "adding anything", though the properties that change may, as Jay Palmer stated, allow bubbles to escape easier (faster). Yes?
Why can I find tutorials where it seems enough to push new oil through and close it up again without bleeding out the bottom and changing angles? Did this video show the example of draining to the bottom for the example of dirty old oil or do you always do it this way?
There certainly different systems to bleed. Shimano's drop levers however do make it more complex to cover because there are several model with different reservoir designs. The concept of tilting the angle is to remove all bubbles that might be trapped at the lever. It is possible to begin by pushing fluid up from the lower caliper and out the top. Then drain fresh fluid down.
I prefer the shortest Free Stroke for max response when I brake. Prior to bleeding, should the Free Stroke screw be backed out so that if a short stroke needs adjusting after bleeding, the screw is in position to allow that adjustment? It would be similar to screwing in the barrel adjuster prior to replacing a mechanical brake cable to allow slack to be tightened.
Treba na to celú pojazdnú dielňu.Zlaté "V" brzdy.Tisice km,jednoduchá montáž, spoľahlivosť, bezpečnosť. Stačilo lanko,pár brzdových špalkov.10. očkový klúč!!!
The extension gets the cup above the rubber hood. The silver one matches the thread of the bleed screw, which is M7 x 0.75. Not all drop bar models however use that thread size.
If the fluid comes out dirty, shouldent i keep pushing until some clean fluid comes out? And, isnt it enough to just push new fluid through the break caliper?
Hi Park Tool, your tutorials are amazing as always and they've helped my partner and myself a lot. May I humbly ask for your advice on this particular issue? The Shimano hydraulic disc brakes on my partner's roadbike have lost their bite, so he decided to bleed them -- bought the correct shimano fluid and kit, opened the plastic screw on the handle and, with the funnel, tried to top off the liquid. He also pumped the brakes to see if any bubbles would come out, but nada. So the brakes are still spongy (the pads are still good, we checked those). Unfortunately, the poor soul wasn't aware that the torque for said plastic screw was like 1Nm, so he pulled it tight when putting it back in - and now it's stuck. The Allen wrench still grips, but it won't budge. Got any advice? Replacement screws are hard to come by these days and apparently this is a common mishap. Should we just take it to the shop or is this something we can tackle on our own? Thank you in advance. Your videos are amazing!
You can try this on your own, and take it in if it does not work. Getting the screw out is going to be the issue. Use a new key and push down on it as your turn to loosen. These are typically steel, check that with a magnet. If there is a large shop they may have a "bone yard", with scavenged parts. See if you can find one. If the brakes are spongy, the bubble may be at the caliper on in the line. Worse case is you need a new lever, which can be done.
The resevoir extension and compression sleeve are clever little extras you have to buy in order to do the job "right". My eyebrow raised even further on seeing the 7mm box wrench. Doesn't it seem odd how even if you buy all the parts and are set to do the build, you are so often ambushed by this kind of faffery.
350kph: Park assumes that the user has a set of tools as do all quality tool sellers. Considering that this tool is usually purchased by professional bicycle mechanics, that's a reasonable assumption. The instructions should include (and probably does) a list of extra tools needed.
Hi I'm bleeding a brand new set of brakes/levers so I assume the "dirty fluid removal" step isn't required after 6:20? If so what would be the next stage after that? Would I just close bleed port on calliper & removal syringe and then do the burping technique? Or do I need to attach something calliper end again ?
If you are working on a new bike there is no need to get rid of the fluid so you can move to the next step of tilting the lever and continue the process.
Thanks for this video! The way you have the bike rotated for bleeding rear brakes @2:08---is it okay to do that with a carbon bike, or will the torque on the seat post and seat tube be too much?
Totally fine to do with a carbon bike. This is a carbon bike in the video. A rider will put hundreds of times more strain on a frame and post than this.
Any reason you cant skip directly to 7:40 and simply bleed the brake system this way, purging all used fluid in the process? This way eliminates introducing air. Its how i used to bleed motorcycle brakes. Much cleaner and faster as well.
That is how Shimano wants it done. They believe that this removes more air bubbles from the system. They have some fun see through acrylic brakes that show where the bubbles hide.
as long as its mineral oil it *should* work. however do on your own risk, if seals go bad after 2 years because the oil did have different properties than the original it would be a shame. its highly unlikely though.
I would like to know if your portable bike stand will hold a specialized turbo levo or is it to heavy for the stand? Wanting to know before I purchase one. Thank you very much.
Looks like the Turbo Levo weighs approximately 51 lbs. The weight capacity of our repair stands varies from 60 lbs. to 120 lbs. depending on the model, so any of our stands should support a bike with that weight. You can find full specs for our repair stands here: www.parktool.com/category/repair-stands
I do not get it: first one pushes new fluid upwards with the syringe, then one lets new fluid drop through the caliper down? Then one pumps repeatedly to have the pump burping? wow - complex procedure, it is easier on a car!
The brake calipers from the GRX series are basically just rebranded calipers from the regular road components series. You might not see it on a new bike but they all work together
@@ethanbowering9944 I'm not disagreeing. I'm having so much difficulty setting up my GRX brakes because *I think* the brifter side of the brake system is different for GRX than 105/Ultegra/Dura ace. But I just don't know. Primarily because the part number for the needle is different in the GRX dealer's installation manual. The needle for the GRX is the silver needle, not the gold one. Just a slight difference. And the connecting nut is not the same part number either. I have twice as much Shimano mineral oil on my carpet as in the brake system.
@@richardbryanesq You can mix and match any current shimano STI and brake calipers (even the 4pot MTB ones to the road/grx STIs and vice versa) regardless of their "level" in the line-up with the SM BH90 brake line. the end parts differ between road and MTB usage and there are some different part numbers because of different colors and so on. f.e. XTR uses a black banjo instead of a silver one and so on. for your GRX/Road mix there is no difference. insert pin and olive on both ends of the brake line. maybe you used the wrong bolt to attach the brake hose? the bolt with the ring around it is for the levers, the one without is for the caliper.
In 2023.. still a HELL NO! Braking power is great but if you don't have the money to take it to a shop every time there's a problem.... I'm sticking to my rim brakes. Can build an entire rim brake bike no prob.
Not let the idea of bleeding turn you away from hydraulic systems. These videos are intended for shops. You rarely need a bleed performed, and the hydraulic systems out perform the mechanical system.
hello. i have a problem with the bleed screw (ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-mAEeAKmCLFU.html) on brake leavers - the internal thread was torn off (most likely ) and bleed screw can not be screwed in (it simply scrolls). What do u recommend in such case? to bore the hole on the leaver and use a bolt with bigger size could be an opportunity?
The bleed screw does not thread in or the threads of the cup do not? This is not common and boring the hole and rethreading is not suggested as it may introduce metal shavings into the system. Which would be bad. A new lever may be a better and often more cost effective solution.
@@parktool 1st one - the bleed screw does not thread in the port. Thread in the port exists. Dont know what the reason of this case. Also described it more here (so I'm not the only one with that issue) - bicycles.stackexchange.com/a/72254/52976
@@alexeiagafonov9715 When you write that "the thread in the port exists," it's not clear what is causing the bleed screw to "scroll," as you say. One of the parts, at least, must be stripped: either the port, or the screw. Maybe buy a replacement bleed screw and see if that works; they're only a few dollars. At least you'll know which part is stripped. This is a terribly frustrating problem. I think in the end you're going to have to get a new lever. I don't think your other solutions are viable.
@@Retro_animation “ equips nerd glasses” actually rim brakes are more aerodynamic dont need to worry about brake fade and are eaquly powerful in dry conditions due to mechanical advantage, however hydraulic brakes work consistently throughout wet dry snowy muddy etc conditions so basically for a road bike get rim brakes for anything else disks
