Still can't express how much I love these Park videos. Calvin is just great - every problem has a calm solution. Years of experience in action. And Truman is his best partner. Long may they continue.
I've seen videos from Calvin and Truman for years. They know how different systems (derailleur / brakes ETC) work and how I can adjust them. Or bleed the brakes wehen needed. I did solve two problems on my bike. I had a squeeking hydraulic disc brake on the front of my bike. After the ideo how to replace brakepads on disc brakes I've taken the wheel and brakepads out and sanded the brakepads. Then placed them back. Placed the wheel back and aligned the calipers. After this the squeek is stopped. The bike is an Giant E-bike that I've been riding for 3847km.
1:304:50 And of course the rotor might be worn down too. 6:00 Moisture should be a concern using DOT (3/4/5.1) fluid, which is hygroscopic. 8:00 Don't mix bleed kits (for mineral oil / DOT)
I had a spongey rear brake lever a few years ago, after bleeding the system it didn't solve the spongey feeling. Noticed that by brake hose bulged when pressing the brake. Found a replacement hose and had to bleed the system again and this fixed it to this day.
Would have to disagree on the deadband point. At least with Magura MT7, there is absolutely variability in deadband based on how much fluid is in the system. The less space between the pads and rotors, the less deadband.
I've got two very different bikes, both disc brakes, and in more than 4 years, I never had to bleed them. They've been working flawlessly like on the first day. I've just replaced the pads many times
"It is recommended that you replace the oil inside the reservoir tank if it becomes severely discolored." Shimano Service Tips. Without apparent issues I might think about oil change in 5-10 years.
Oh my, great timing. I'm gonna do that to my Shimano MT200 brakes, since it was installed from 3 different bikes, until it landed on my wife's folding bike.
Gentlemen: we love These videos and find them so useful. As long as the brakes feel crisp, I find it easiest and most efficient to bleed the brakes whenever I need to change the brake pads. On several occasions, I’ve had a brake that feels spongy, soft or pulls to the bar; the problem was not solved by a bleed and it turned out the pads were worn out **or** the rotor was too thin. I am always amazed at the engineering that allows these things to be so dialed that when the rotor is like 0.3 mm thinned out, you can feel it at the lever…
Hello. First of all I like your channel very much. A lot to learn. Maybe you can advise on what I should try: I have this issue on my Tern gsd: back light not working at all. It is a tail light but also a brake light. None of the 2 ways is working.. . It stopped working after the shop changed the brake pads. Coincidence? I have no idea.... Need to mention I inspecter wire to tai light and all looks fine. (that wire visible; parts are in the frame) . What else should I try before removing wires from frame for inspection? Thanks in advance!
I have a set of AVID hydraulic brakes on my MTB. Last week I just randomly grabbed the brake lever while the bike was on the wallmount and noticed there was no resistance. I spun the wheel and grabbed the lever and sure enough, the brake pistons were not engaging. No more than an hour later, I tried and again and it worked and was fully functioning correctly. I inspected the brake line starting from the brake lever and followed it all the way to the rear caliper and did not notice any fluid leaks. Might you know why the system wasn't randomly not working initially ? Any comment greatly apprec.
i've had the same issue and I'm going to copy & paste park tool's response to @Noily on this topic - "Varying deadband points towards a migrating bubble/ small bubbles near the lever. A bleed will help resolve that issue"
My MTB had disc brake rubbing issues from the start. 4 different mechanics working in different stores worked on it + myself weaponized with YT video's. We all weren't able to solve it. One mechanic even said that it was the size of the disc. As if all downhill racers come of the mountain as Santa Clauses rinkeling and kinkeling (so I kinda dodge him for now). My discs weren't event that large (180mm). For my roadbike the alignment is easily done by just pushing in an alignment helper tool. Unscrew the bolts, squeeze the brake and then tying up the bolts again. But the MTB kept having issues. It got so far that I even changed the complete brake system to XT but it still keeps rubbing. It's crazy to think that this is a new MTB in the 5000 - 6000 price range. So what happens with the MTB is that after (difficult) alignment, just after 1-2 km of riding and a few times braking, the calipers got back to their misaligned position. Event when bolting them very tight. I read about that the mounting surfaces on the fork not being flat could also cause rubbing. The mount facing tools to fix that are very expensive and for just one go I won't buy it. So I brought it to the bikes brand store and they faced the surfaces. After that the alignment was centered, but now after braking the rubbing starts again and then after a couple of seconds (5-10) the rubbing dissapears. Very.. very frustrating. After more braking it's worse than after having ridden a longer piece without braking. So it seems to have something to do with heat, but maybe also with pressure changes. Just before I brought it to the shop I also let a bit of oil out as I read that the pistons cannot retract fully if the brakes are 'overbled'. I now ordered my own bleed kit hoping that a new bleed will finally solve this issue by eliminating pressure changes. If it's not that... I guess the only option is to sell the MTB. Everything has been tried.
The first time that I own a disk brake with a hydraulic system and I always wanted to buy a bike with that but interesting how bleeding the system is so mention over and over and get it done every year or so depending on your riding use. I said interesting because cars have a hydraulic system but never need bleeding ever unless broken lines of course. I will dig into what is causing that bleeding maintenance once a year or so. But the good thing is a bike has a ton of room and it is super light to work with.
Hydraulic fluid change is also part of car maintenance, but usually less frequently than oil changes. On my bike I guess I'll think of it in 5-10 years, since I'm not riding 10-15,000 km a year...
Car brakes absolutely need bleed as regular maintenance. If you look at the brake fluid reservoir, it should be a clear, maybe slightly tinted, liquid. If your fluid is a brownish black, your brake fluid has absorbed moisture and broken down over time. This fluid may work, but heats up and performs worse over time.
I had a problem with some Shimano brakes where they were fine until I started bombing downhill and then got spongy. After a few minutes on the flats and climb back up, they were fine. After more downhill, spongy again. Bleed fixed it. Must have been just enough air that when it got heated up during the downhill braking, it expanded enough to feel the sponginess I guess?
what about a reason one should bleed their brakes is when you put the bike up on its rear wheel and all of a sudden one of your brakes go super mushy/lever to bar? (as being a test of when one should bleed).
Guys can you help me i have Magura MT5 but i bought a oilslick rotor and now it aint working as good as the original does it need a bleed i think it may be thinner than the magura rotors
I have to do this regularly, because no matter how often or how meticulously I bleed my rear brake, its lever throw/deadband always creeps up to be longer than that of my front brake. I can fix this temporarily by pulling the lever and tying it to the handle bar in the pulled position (which forces the pistons to come closer to the brake rotor, reducing the amount of lever throw/deadband), but this effect diminishes over time (mostly just one ride) and so I'll have to do it again.
3:40 if your brakes squeak like that you probably missed the bleed window and your piston seals are leaking. Ihat this issue with tektro drako and shimano mt 200s Boiling your brakes can also cause a leak at both the pistons and the master cylinder seals
@@mountaindweller4514 the bleed window is when contaminants start getting into the system upto where they start leaking. Boiling is when the mineral oil or dot get's so hot it boils. The fluid becomes the consistency of water and either bulges the tubing or the fluid gets by the seals. If you use metallic pads the heat gets transferred to the calliper then the fluid, the fluid expands and creates pressure. That's why there's a rubber diaphragm in the lever. If you use resin pads most of the heat goes to the rotor and causes brake fade
Just when I started to forget that I'm never going to be able to buy Trickstuff brakes you guys feature them in a video. I thought I was safe by avoiding any footage with the Athertons in it. :)
My rear brake lever is closer to the bar than the front, i think its the hose length.and the pads on new sram level TL are thin so im soL In adjusting the lever play
I have noticed the last time that I replaced my brake pads that the piston are getting hard to push back fully in. I guess that's an indication I need to bleed? It's a SRAM with DOT fluid, I heard they absorb moisture over time. So my guess is the system is getting more full?
You must be talking about the HY/RD, which can be bled and yes, brake fluid can get dirty with use overtime, so they still require bleeding. Also, try not to have a habit of assuming things. It can get you into trouble one day. I've seen so many riders assuming things left and right, which did get them into trouble.
We have made quite a few changes. Reach out to info@parktool.com with images and descriptions of the issues you are having. They will get you all sorted out.
@@doylerabjohn3435 If you ride in rain sometimes, you will feel much more confident with disc brakes. Even the cable operated ones should be good (they dont have that much power as hydros usually, but they are bombproof and they work exactly like rim brakes with cables)
@@RealMTBAddict Because 1) I don't live in the mountains, and 2) I rarely ride in the rain anymore, and 3) I retired from racing, 5 years ago, after 32 years on the circuit.
When my brakes heat up from a long descent, the pads start contacting the rotors by themselves and drag even if i am not pulling on the levers anymore. It is as if the fluid expanded from the heat because the situation goes back to normal if i let the brakes cool, but this means i have to get off the bike and walk down the hill for safety until the brakes cool down. Can this be solved by bleeding?
I dont see why different oil would make a difference there. Maybe its an issue of allignment and there is not enough space in between the brake pads and disks?
How long has it been since the brakes have been bled? In theory it's possible that there is moisture in the fluid making it expand more when heated. As the previous response says it's possible that there is an alignment issue compounding the expansion issue. It's also important to say that a little noise from your brakes like that does not mean you need to get off the bike till they cool. Just keep having a ball going down hill and they will cool on the flats or ascent.
Sounds like rotor warping to me. If your rotors look discoloured (you'll see some purple-blue shades), there's a chance it's warped and will only get worse whenever it's hot. Caliper centering is another thing worth checking too.
@@sbccbc7471 I just burned my new Shimano SM-RT54 rotor while bedding-in on a steep descent. Strong smell from the pads and the surface in contact with them was brownish. I wasn't even fast, maybe 30-40 km/h max, but repeated at close interval. No apparent damage though, they have now turned into a golden/bronze color, with some bluish/blackish reflections. Also the model mounted on the stock wheels was Shimano SM-RT10, I'm not even sure which one is better, they are both $10-20 locally, and "for resinpads only"...
Yes, disc brake are a real PIA when it comes to maintenance and settings. They are really more powerful and a bit faster, but I don't see a real need for road bikes, if you can ride at high speeds you should have enough strength to brake with good rim pads.
The fluid might not have had enough time to go back into the reservoir. The more viscous (thicker) the fluid and the colder the environment is, the more pronounced this issue can appear. Some Shimano brakes have (had?) this issue, apparently the bores were a bit too small with the default Shimano mineral oil in cold weather. For most people, switching to a less viscous/"lighter" brake fluid resolved the issue (Magura Royal Blood is less viscous than Shimano, there are other brands as well). It may void your warranty though, most manufacturers tell you to use only their brake fluid. But whatever you do, never mix up mineral oil and DOT brake fluid, these will destroy your brakes if used in one that was designed for the other.
@@andygilbert1877It depends on the initial state of the lever. If the first squeeze feels normal, and like the other brake, but the amount of travel for the lever reduces after that, then likely there's no air in the system. However if the first squeeze feels squishy and with too much lever travel, and the subsequent squeezes brings this back to normal, than very likely the brake needs to be bled, as it's the air in the hose that's being forced back into the reservoir that's causing this behavior.
I am not sure if I need to bleed my brakes but after every big jump my brake levers suddenly become lose all the way to the handlebar but after a few seconds it return back to normal, I think there is a bubble of air that is traped in a place that normally doesn't affect that much on the brakes but after big jump the bubble move to a different place which make it affect more on the brakes , also the brakes feel kind of sticky and I think the fluid is a bit old so I might change the fluid anyway What do you think?
last week when I was disassembling my brakes for cleaning, I thought I was safe to separate the housing/shell that the pads sit in. As the hydraulic hose went into only 1 side of the calliper I figured that it was just a single piston brake, most of the cars I've had were single piston so didn't think much of a bike only having 1, it is much lighter after all. Unfortunately this assumption was quickly put to bed as when I pulled the outermost side of the calliper away I seen fluid leaking down my forks. I persevered with the cleaning and reassembled, the front brake lever bottomed out on the first squeeze, with no mineral oil to put in I just had to make do with getting as much air out and then closing the res screw, the brake isn't as sharp as the back, but it can still lock up the front wheel if I wanted it to.
One of my service customers came to me after they tried readjusting the front disc brake by cracking loose what they thought were the mounting bolts, but are actually the caliper body's bolts that hold the two halves together. This mistake costs them a set of new pads (old one was drenched in hydraulic fluid and was barely worn) and a full bleed. Of course, the rotor was cleaned too.
"It is recommended that you replace the oil inside the reservoir tank if it becomes severely discolored." Shimano. Mineral oil can last for decades (at normal temperatures)... Did you own any SRAM hydraulic brakes?
baght a brand new bike the supplier online supplier had popped cover off the reservoirs to put oil in i got bike brakes so spongy was unbelievable took 5 mins with the correct bleed kit but my point being even so called built bikes the mechanics that work on them pretty low quality and the worst thing was the so called bike engineer mechanic spilt dot 4 fluid all-over the levers stripping off the paint was verry disappointed
The main thing I hope for is that the industry at some point agree on the best way to bleed hydraulic systems. I'm quite stunned about how much confusion there can be to such a simple process. Here's a rule of thumb: *_Believe none of what you hear, and half of what you see._*
Does anybody else struggle bus on bleeding the lever of Sram's guide series of brakes. Caliper always bleeds no problem, but the lever takes like 20-30 minutes at times. much struggle. I prefer Most Tektro, shimano, and avids, or codes.
When my bike is upside down or just wheeling the bike on the front wheel the lever comes all the way to the bar and the pads have no movement. But when it’s upright and riding they feel great should I bleed my brakes upside down?
When your bike is upside down, the air goes into the hose, where it causes the problems. In it's normal position, the air should be in the reservoir, where it doesn't (shouldn't) affect the operation of the brake (that's the very reason these reservoirs exist, to provide additional oil due to wear and to trap any air). Yes, you have air in your system, but no, you should not bleed it upside down.
@@DR_1_1 Filling up the top of the reservoir is basically a "quick bleed" and is in fact what I'm doing most of the time. You do need some sort of funnel though (like the ones used for the Shimano brakes, but an open syringe will also do), and activate the brake lever multiple times, to force out any air bubbles present in the Retrovir and brake hose. Also shift the position of the brake lever up/down and knock on it with a screwdriver or something, to get these air bubbles moving. You most likely won't get any air trapped in the saddle this way, for which you will need to do a full bleed, but most of the time this will already greatly improve the breaking performance. Do note however that if your brake pads and/or rotor is already worn, you're basically "overfilling" your brake system this way. Which means that there's a good chance that you won't be able to fit new pads without also opening the bleed screw, because you won't be able to push the pistons back far enough so that they will fit over the rotor. It's a minor issue, but you need to be aware of it. I.e. always have the tool to open the bleed screw at hand when you might need to change your brake pads (i.e. on the middle of trail with no one around you).
@@sp00n Thanks for the details and tips. This is my first bike with disc brakes, and compared to rim brakes it's quite a PITA already... it took me days to bed-in the stock discs, and now I messed up with a new one by doing it in a descent, burning the brake despite moderate speeds - hopefully without damage. I'll stick to Shimano's instructions, bedding-in on flat terrain (or with extra care), and bleeding the oil only when it's discolored (mineral oil should last for decades at normal temperatures).
hi Calvin , hi Truman , I found the ceramic pistons of road calipers frozen(one side not moving).because the riders use there bikes occasionally. why it is happening and how to prevent that.
Pull the pads and wheel out. Hold down the piston that is moving, by pressing it with a plastic tire lever, while you pull the brake lever. The stuck piston should start moving. Press it back in and out a few times. Then reset both pistons all the way in, replace the pads and wheel, readjust the brake, and you're done. To prevent it you can lubricate the sides of the piston using a cotton swab soaked in the brake's correct hydraulic fluid. But be sure to clean up the excess before any can touch the brake pads or rotor.
Regarding annual bleeding for maintenance: not always! "All MAGURA brakes use low viscosity mineral oil (Royal Blood) as hydraulic medium. Contrary to DOT brake liquid it does not irritate human skin nor damage the paint off your frame. Biggest asset: It does not absorb water and actually lubricates the whole system. Regular bleeding caused of old brake liquid is therefore not necessary!"
Same for Shimano: "It is recommended that you replace the oil inside the reservoir tank if it becomes severely discolored." Mineral oil can last for DECADES (at normal temperatures). If it ain't broke, don't fix it...
Once a year at a minimum. Just like a car the fluid gets dirty and breaks down and can cause seals to fail as well as just good up keep. Doesn't take long and you have the knowledge of knowing your fluid is clean and air free if you know what you're doing.
Too bad Park Tools distributor sucks in western Canada: delivery time is unacceptable, and combined with limited availability, I turned to other tool brand to wrench my bike.
Sorry to hear you’ve had a bad experience - we do have four distributors in Canada so feel free to reach out to another one if you need anything else of ours: www.parktool.com/en-us/trade-resources/worldwide-distributors
Why the hell did bike companies foist these ridiculous devices on us? Rim brakes aren't prone to a tenth of the problems and they're just as effective.
You should never have to bleed your brakes, a push bike is meant to be a simple mechanism that can be worked on with basic simple tools, and anyone that thinks disc brakes make u stop in a shorter distance needs to go back and learn grade 10 physics
Still can't express how much I love these Park videos. Calvin is just great - every problem has a calm solution. Years of experience in action. And Truman is his best partner. Long may they continue.
Yes! It totally agree. Those two are great. And so is Park Tool.
Those additional examples with the syringes are a great touch to understand the whole system , Calvin
🙌
I did some bleeding at my clients lately. Tried to induce syncope. Helps well to treat the breathing of bad air. Everyone trusts the barber surgeon
Did you use the Park Tool LH-1 leech tools?
A right good purging of miasma always enlivens the nobler humours.
I've seen videos from Calvin and Truman for years.
They know how different systems (derailleur / brakes ETC) work and how I can adjust them.
Or bleed the brakes wehen needed. I did solve two problems on my bike.
I had a squeeking hydraulic disc brake on the front of my bike.
After the ideo how to replace brakepads on disc brakes I've taken the wheel and brakepads out and sanded the brakepads.
Then placed them back. Placed the wheel back and aligned the calipers. After this the squeek is stopped.
The bike is an Giant E-bike that I've been riding for 3847km.
1:30 4:50 And of course the rotor might be worn down too.
6:00 Moisture should be a concern using DOT (3/4/5.1) fluid, which is hygroscopic.
8:00 Don't mix bleed kits (for mineral oil / DOT)
I had a spongey rear brake lever a few years ago, after bleeding the system it didn't solve the spongey feeling. Noticed that by brake hose bulged when pressing the brake. Found a replacement hose and had to bleed the system again and this fixed it to this day.
Would have to disagree on the deadband point. At least with Magura MT7, there is absolutely variability in deadband based on how much fluid is in the system. The less space between the pads and rotors, the less deadband.
I've got two very different bikes, both disc brakes, and in more than 4 years, I never had to bleed them. They've been working flawlessly like on the first day. I've just replaced the pads many times
Same as my brake 3 years and countinh without bleeding just change pads and topping up some mineral oil at reservoir
"It is recommended that you replace the oil inside the reservoir tank if it becomes severely discolored." Shimano Service Tips.
Without apparent issues I might think about oil change in 5-10 years.
Oh my, great timing. I'm gonna do that to my Shimano MT200 brakes, since it was installed from 3 different bikes, until it landed on my wife's folding bike.
Nice video,and very helpful. Many thanks from GREECE.
Gentlemen: we love
These videos and find them so useful. As long as the brakes feel crisp, I find it easiest and most efficient to bleed the brakes whenever I need to change the brake pads. On several occasions, I’ve had a brake that feels spongy, soft or pulls to the bar; the problem was not solved by a bleed and it turned out the pads were worn out **or** the rotor was too thin. I am always amazed at the engineering that allows these things to be so dialed that when the rotor is like 0.3 mm thinned out, you can feel it at the lever…
I have the Formula brakes with the SpeedLock hoses. Does it really work, and I won't need to bleed them after reconnection?
Hello. First of all I like your channel very much. A lot to learn. Maybe you can advise on what I should try: I have this issue on my Tern gsd: back light not working at all. It is a tail light but also a brake light. None of the 2 ways is working.. . It stopped working after the shop changed the brake pads. Coincidence? I have no idea.... Need to mention I inspecter wire to tai light and all looks fine. (that wire visible; parts are in the frame) . What else should I try before removing wires from frame for inspection? Thanks in advance!
Park Tool coming in clutch as always
I have a set of AVID hydraulic brakes on my MTB. Last week I just randomly grabbed the brake lever while the bike was on the wallmount and noticed there was no resistance. I spun the wheel and grabbed the lever and sure enough, the brake pistons were not engaging. No more than an hour later, I tried and again and it worked and was fully functioning correctly. I inspected the brake line starting from the brake lever and followed it all the way to the rear caliper and did not notice any fluid leaks. Might you know why the system wasn't randomly not working initially ? Any comment greatly apprec.
i've had the same issue and I'm going to copy & paste park tool's response to @Noily on this topic - "Varying deadband points towards a migrating bubble/ small bubbles near the lever. A bleed will help resolve that issue"
@@garrettcirrincione3208 thanks for the reply Garrett. Bummer for me, means I'm gonna have to take my bike into the shop and have them service it.
My MTB had disc brake rubbing issues from the start. 4 different mechanics working in different stores worked on it + myself weaponized with YT video's. We all weren't able to solve it. One mechanic even said that it was the size of the disc. As if all downhill racers come of the mountain as Santa Clauses rinkeling and kinkeling (so I kinda dodge him for now). My discs weren't event that large (180mm). For my roadbike the alignment is easily done by just pushing in an alignment helper tool. Unscrew the bolts, squeeze the brake and then tying up the bolts again. But the MTB kept having issues. It got so far that I even changed the complete brake system to XT but it still keeps rubbing. It's crazy to think that this is a new MTB in the 5000 - 6000 price range.
So what happens with the MTB is that after (difficult) alignment, just after 1-2 km of riding and a few times braking, the calipers got back to their misaligned position. Event when bolting them very tight. I read about that the mounting surfaces on the fork not being flat could also cause rubbing. The mount facing tools to fix that are very expensive and for just one go I won't buy it. So I brought it to the bikes brand store and they faced the surfaces. After that the alignment was centered, but now after braking the rubbing starts again and then after a couple of seconds (5-10) the rubbing dissapears. Very.. very frustrating. After more braking it's worse than after having ridden a longer piece without braking. So it seems to have something to do with heat, but maybe also with pressure changes. Just before I brought it to the shop I also let a bit of oil out as I read that the pistons cannot retract fully if the brakes are 'overbled'.
I now ordered my own bleed kit hoping that a new bleed will finally solve this issue by eliminating pressure changes. If it's not that... I guess the only option is to sell the MTB. Everything has been tried.
The first time that I own a disk brake with a hydraulic system and I always wanted to buy a bike with that but interesting how bleeding the system is so mention over and over and get it done every year or so depending on your riding use. I said interesting because cars have a hydraulic system but never need bleeding ever unless broken lines of course. I will dig into what is causing that bleeding maintenance once a year or so. But the good thing is a bike has a ton of room and it is super light to work with.
Hydraulic fluid change is also part of car maintenance, but usually less frequently than oil changes.
On my bike I guess I'll think of it in 5-10 years, since I'm not riding 10-15,000 km a year...
Car brakes absolutely need bleed as regular maintenance. If you look at the brake fluid reservoir, it should be a clear, maybe slightly tinted, liquid. If your fluid is a brownish black, your brake fluid has absorbed moisture and broken down over time. This fluid may work, but heats up and performs worse over time.
I had a problem with some Shimano brakes where they were fine until I started bombing downhill and then got spongy. After a few minutes on the flats and climb back up, they were fine. After more downhill, spongy again. Bleed fixed it. Must have been just enough air that when it got heated up during the downhill braking, it expanded enough to feel the sponginess I guess?
You two are both entertaining and very informative!!
Good thing to watch this video, I recently switched from mech to hydraulics.
thnks guys yet again for another great video, I have bled loads of breaks on cars so I geuss the principal is the same.....yeah ?
Very similar but often more finicky than a car.
Pretty much yeah, bit more care needed but the principle is the same.
Its always amazing to me how much easier bleeding my car is than my bike.
what about a reason one should bleed their brakes is when you put the bike up on its rear wheel and all of a sudden one of your brakes go super mushy/lever to bar? (as being a test of when one should bleed).
Guys can you help me i have Magura MT5 but i bought a oilslick rotor and now it aint working as good as the original does it need a bleed i think it may be thinner than the magura rotors
What about tying the lever back to the bars when you know you've got air but can't bleed them now (no fluid or no bleed kit)
I have to do this regularly, because no matter how often or how meticulously I bleed my rear brake, its lever throw/deadband always creeps up to be longer than that of my front brake.
I can fix this temporarily by pulling the lever and tying it to the handle bar in the pulled position (which forces the pistons to come closer to the brake rotor, reducing the amount of lever throw/deadband), but this effect diminishes over time (mostly just one ride) and so I'll have to do it again.
That works well, I use a zip tie & leave them overnight.
3:40 if your brakes squeak like that you probably missed the bleed window and your piston seals are leaking. Ihat this issue with tektro drako and shimano mt 200s
Boiling your brakes can also cause a leak at both the pistons and the master cylinder seals
what does "missing the bleed window" and "boiling your brakes" mean?
@@mountaindweller4514 the bleed window is when contaminants start getting into the system upto where they start leaking.
Boiling is when the mineral oil or dot get's so hot it boils. The fluid becomes the consistency of water and either bulges the tubing or the fluid gets by the seals.
If you use metallic pads the heat gets transferred to the calliper then the fluid, the fluid expands and creates pressure. That's why there's a rubber diaphragm in the lever.
If you use resin pads most of the heat goes to the rotor and causes brake fade
Just when I started to forget that I'm never going to be able to buy Trickstuff brakes you guys feature them in a video. I thought I was safe by avoiding any footage with the Athertons in it. :)
I literally bled my brakes earlier today because of #1. Thanks @park tool!
@@RealMTBAddict I figuratively did!
This was a great one, so useful! Thanks Calvin and Truman 😊
At the end, you can see that the D.O.T. fluid logo on the bleed kit is worn away (because dot fluid ruins paint) but the mineral oil kit isn't.
When people say its not recommended to turn around your bike to work on it because air will go to your calipers, I tell them “you need a bleedin”
My rear brake lever is closer to the bar than the front, i think its the hose length.and the pads on new sram level TL are thin so im soL In adjusting the lever play
That sounds like your rear brake line wasn't fully bled. Rear brake lines are usually a little harder to fully bleed than the front.
Attach an elastic band to keep the lever pressed, and leave it for the night. It should be firmer in the morning.
Hello park tool crew! 👋
Hadn't bled the brakes in 5 years of ownership, did it today and it felt wayyy better.
Interestingly raw power was similar 🤷♂️
I have noticed the last time that I replaced my brake pads that the piston are getting hard to push back fully in. I guess that's an indication I need to bleed? It's a SRAM with DOT fluid, I heard they absorb moisture over time. So my guess is the system is getting more full?
That is correct. Its likely that they have taken on additional moisture through the seals and other areas.
Hi Calvin! Nice video!
I have mechanically actuated disc brakes, TRPs. I assume they can't be bled, but do I ever need to change the mineral oil fluid?
You must be talking about the HY/RD, which can be bled and yes, brake fluid can get dirty with use overtime, so they still require bleeding.
Also, try not to have a habit of assuming things. It can get you into trouble one day. I've seen so many riders assuming things left and right, which did get them into trouble.
Hey, Did you guys improve your bleed kit? I bought one last year and we had issues with the hose leaking and popping off
We have made quite a few changes. Reach out to info@parktool.com with images and descriptions of the issues you are having. They will get you all sorted out.
Hi Calvin…and Truman ofcourse ❤❤❤
Thanks, Never had disk brakes, the last 40 years. I allways ran rim brakes. I am going to upgrade my trek ( '02 ) ? to disk (was a option then).
do it, at least in the front. rim brakes are great, but they dont work in rain very well
@@RealMTBAddict Thanks
@@ondrejmanych5688 Thanks. I am in a hurricane State
@@doylerabjohn3435 If you ride in rain sometimes, you will feel much more confident with disc brakes. Even the cable operated ones should be good (they dont have that much power as hydros usually, but they are bombproof and they work exactly like rim brakes with cables)
Hi Calvin.
Thank God for caliper type rim brakes on my road bikes, and "V" type rim brakes on my mountain bike.
@@RealMTBAddict Because 1) I don't live in the mountains, and 2) I rarely ride in the rain anymore, and 3) I retired from racing, 5 years ago, after 32 years on the circuit.
@@RealMTBAddict Why downgrade to disc brakes when you have something that works just as well?...Do you race in the rain?
When my brakes heat up from a long descent, the pads start contacting the rotors by themselves and drag even if i am not pulling on the levers anymore. It is as if the fluid expanded from the heat because the situation goes back to normal if i let the brakes cool, but this means i have to get off the bike and walk down the hill for safety until the brakes cool down. Can this be solved by bleeding?
I dont see why different oil would make a difference there. Maybe its an issue of allignment and there is not enough space in between the brake pads and disks?
How long has it been since the brakes have been bled? In theory it's possible that there is moisture in the fluid making it expand more when heated. As the previous response says it's possible that there is an alignment issue compounding the expansion issue. It's also important to say that a little noise from your brakes like that does not mean you need to get off the bike till they cool. Just keep having a ball going down hill and they will cool on the flats or ascent.
Sounds like rotor warping to me. If your rotors look discoloured (you'll see some purple-blue shades), there's a chance it's warped and will only get worse whenever it's hot. Caliper centering is another thing worth checking too.
@@sbccbc7471 yes, Shimano had this issue with its road rotors when they were first released.
@@sbccbc7471 I just burned my new Shimano SM-RT54 rotor while bedding-in on a steep descent. Strong smell from the pads and the surface in contact with them was brownish. I wasn't even fast, maybe 30-40 km/h max, but repeated at close interval.
No apparent damage though, they have now turned into a golden/bronze color, with some bluish/blackish reflections.
Also the model mounted on the stock wheels was Shimano SM-RT10, I'm not even sure which one is better, they are both $10-20 locally, and "for resinpads only"...
Hi Calvin !
Well done.
My deadband will vary. Sometimes brake lever goes close to handle bar but after release and pull it again, it'll be back to normal
Varying deadband points towards a migrating bubble/ small bubbles near the lever. A bleed will help resolve that issue.
Hi Truman!
Should have thrown a couple of tips for hydraulic v-brakes too. Are these kits compatible with Magura v-brakes too?
If they have matching threads for the fittings, it should be compatible.
Hey Calvin, bleeding didn't solve my prob. My bike was stolen and a bleed didn't help 😁😁
Nitpicking you Truman. Air is a fluid too. 😉. But......Great information as usual. Thanks guys.
Oh you're just gassy ;) Good catch.
Deadband? Bleeding? Screw that noise! If or...when I switch to disc brake I'll go for cable actuated with compression-less housing.
Yes, disc brake are a real PIA when it comes to maintenance and settings. They are really more powerful and a bit faster, but I don't see a real need for road bikes, if you can ride at high speeds you should have enough strength to brake with good rim pads.
Hi, Calvin!
What's about when the lever becomes firm or actuates earlier in the lever throw after a few squeezes?
The fluid might not have had enough time to go back into the reservoir. The more viscous (thicker) the fluid and the colder the environment is, the more pronounced this issue can appear. Some Shimano brakes have (had?) this issue, apparently the bores were a bit too small with the default Shimano mineral oil in cold weather.
For most people, switching to a less viscous/"lighter" brake fluid resolved the issue (Magura Royal Blood is less viscous than Shimano, there are other brands as well). It may void your warranty though, most manufacturers tell you to use only their brake fluid.
But whatever you do, never mix up mineral oil and DOT brake fluid, these will destroy your brakes if used in one that was designed for the other.
That sounds like it needs bleeding!
@@andygilbert1877It depends on the initial state of the lever. If the first squeeze feels normal, and like the other brake, but the amount of travel for the lever reduces after that, then likely there's no air in the system.
However if the first squeeze feels squishy and with too much lever travel, and the subsequent squeezes brings this back to normal, than very likely the brake needs to be bled, as it's the air in the hose that's being forced back into the reservoir that's causing this behavior.
Hi Calvin 👋
ha I know those guys! I was looking for automotive stuffs lol, been watching alot cyclinng for the algotrythm
I am not sure if I need to bleed my brakes but after every big jump my brake levers suddenly become lose all the way to the handlebar but after a few seconds it return back to normal, I think there is a bubble of air that is traped in a place that normally doesn't affect that much on the brakes but after big jump the bubble move to a different place which make it affect more on the brakes , also the brakes feel kind of sticky and I think the fluid is a bit old so I might change the fluid anyway
What do you think?
Flush and bleed them. While the lines are empty, check the calipers and levers to work on getting rid of the stickiness.
@@sbccbc7471 I will try it , thank you 🔥
last week when I was disassembling my brakes for cleaning, I thought I was safe to separate the housing/shell that the pads sit in. As the hydraulic hose went into only 1 side of the calliper I figured that it was just a single piston brake, most of the cars I've had were single piston so didn't think much of a bike only having 1, it is much lighter after all. Unfortunately this assumption was quickly put to bed as when I pulled the outermost side of the calliper away I seen fluid leaking down my forks. I persevered with the cleaning and reassembled, the front brake lever bottomed out on the first squeeze, with no mineral oil to put in I just had to make do with getting as much air out and then closing the res screw, the brake isn't as sharp as the back, but it can still lock up the front wheel if I wanted it to.
One of my service customers came to me after they tried readjusting the front disc brake by cracking loose what they thought were the mounting bolts, but are actually the caliper body's bolts that hold the two halves together. This mistake costs them a set of new pads (old one was drenched in hydraulic fluid and was barely worn) and a full bleed. Of course, the rotor was cleaned too.
I have been mountain biking for 25 years and I have never bled my brakes on any of my bikes.
"It is recommended that you replace the oil inside the reservoir tank if it becomes severely discolored." Shimano.
Mineral oil can last for decades (at normal temperatures)...
Did you own any SRAM hydraulic brakes?
One solution, i ditched hydraulics, reverted back to caliper, hydraulics are only exclusive for mtb downhillers i think
baght a brand new bike the supplier online supplier had popped cover off the reservoirs to put oil in i got bike brakes so spongy was unbelievable took 5 mins with the correct bleed kit but my point being even so called built bikes the mechanics that work on them pretty low quality and the worst thing was the so called bike engineer mechanic spilt dot 4 fluid all-over the levers stripping off the paint was verry disappointed
My breaks are releasing a lot of air. How can that be fixed. Very hard for me to stop my Dodge caravan
Easy fix, buy a Toyota or Honda.
@@DR_1_1I'm homeless and need a van. I have been trying to purchase a used Honda van but people buy them up so quickly.
The main thing I hope for is that the industry at some point agree on the best way to bleed hydraulic systems. I'm quite stunned about how much confusion there can be to such a simple process.
Here's a rule of thumb: *_Believe none of what you hear, and half of what you see._*
Does anybody else struggle bus on bleeding the lever of Sram's guide series of brakes. Caliper always bleeds no problem, but the lever takes like 20-30 minutes at times. much struggle. I prefer Most Tektro, shimano, and avids, or codes.
When my bike is upside down or just wheeling the bike on the front wheel the lever comes all the way to the bar and the pads have no movement. But when it’s upright and riding they feel great should I bleed my brakes upside down?
When your bike is upside down, the air goes into the hose, where it causes the problems. In it's normal position, the air should be in the reservoir, where it doesn't (shouldn't) affect the operation of the brake (that's the very reason these reservoirs exist, to provide additional oil due to wear and to trap any air).
Yes, you have air in your system, but no, you should not bleed it upside down.
When the bike's upside-down, DO NOT actuate the brakes.
@@sp00n Can't you just top the oil in the reservoir in this case, without bleeding?
I'm just curious, I'm still far from having to bleed my brakes.
@@DR_1_1 Filling up the top of the reservoir is basically a "quick bleed" and is in fact what I'm doing most of the time.
You do need some sort of funnel though (like the ones used for the Shimano brakes, but an open syringe will also do), and activate the brake lever multiple times, to force out any air bubbles present in the Retrovir and brake hose. Also shift the position of the brake lever up/down and knock on it with a screwdriver or something, to get these air bubbles moving.
You most likely won't get any air trapped in the saddle this way, for which you will need to do a full bleed, but most of the time this will already greatly improve the breaking performance.
Do note however that if your brake pads and/or rotor is already worn, you're basically "overfilling" your brake system this way. Which means that there's a good chance that you won't be able to fit new pads without also opening the bleed screw, because you won't be able to push the pistons back far enough so that they will fit over the rotor.
It's a minor issue, but you need to be aware of it. I.e. always have the tool to open the bleed screw at hand when you might need to change your brake pads (i.e. on the middle of trail with no one around you).
@@sp00n Thanks for the details and tips. This is my first bike with disc brakes, and compared to rim brakes it's quite a PITA already... it took me days to bed-in the stock discs, and now I messed up with a new one by doing it in a descent, burning the brake despite moderate speeds - hopefully without damage.
I'll stick to Shimano's instructions, bedding-in on flat terrain (or with extra care), and bleeding the oil only when it's discolored (mineral oil should last for decades at normal temperatures).
Thanks for the video!
Tuesdays.... At 3:45am...
That was fun and informative. 😂thank you
Is elementary 😁 Thank you à bientôt 👍
Whats up Calvin! Thanks for the tips. You too Truman
hehe very helpful video!
hi Calvin , hi Truman , I found the ceramic pistons of road calipers frozen(one side not moving).because the riders use there bikes occasionally. why it is happening and how to prevent that.
Pull the pads and wheel out. Hold down the piston that is moving, by pressing it with a plastic tire lever, while you pull the brake lever. The stuck piston should start moving. Press it back in and out a few times. Then reset both pistons all the way in, replace the pads and wheel, readjust the brake, and you're done. To prevent it you can lubricate the sides of the piston using a cotton swab soaked in the brake's correct hydraulic fluid. But be sure to clean up the excess before any can touch the brake pads or rotor.
Regarding annual bleeding for maintenance: not always!
"All MAGURA brakes use low viscosity mineral oil (Royal Blood) as hydraulic medium. Contrary to DOT brake liquid it does not irritate human skin nor damage the paint off your frame. Biggest asset: It does not absorb water and actually lubricates the whole system. Regular bleeding caused of old brake liquid is therefore not necessary!"
Same for Shimano: "It is recommended that you replace the oil inside the reservoir tank if it becomes severely discolored."
Mineral oil can last for DECADES (at normal temperatures).
If it ain't broke, don't fix it...
Once a year at a minimum. Just like a car the fluid gets dirty and breaks down and can cause seals to fail as well as just good up keep. Doesn't take long and you have the knowledge of knowing your fluid is clean and air free if you know what you're doing.
I bleed mine on all three bikes about every 6 months
I prefer to call it "bloodletting"
Great video!…very informative!…sure am glad I got mechanical brakes!…all that bleeding sounds complicated!…😎
BLEEDUHBLEED 0:47
Too bad Park Tools distributor sucks in western Canada: delivery time is unacceptable, and combined with limited availability, I turned to other tool brand to wrench my bike.
Sorry to hear you’ve had a bad experience - we do have four distributors in Canada so feel free to reach out to another one if you need anything else of ours: www.parktool.com/en-us/trade-resources/worldwide-distributors
Thanks for replying! :) Didnt know we had 4. I’ll try others and see how it works. 🔧
Is it even possible to boil the mineral oil in your brake lines? We're not driving cars here or have the brake force the same as a vehicle!
Yes, heavy rider or cargo bike, riding the brakes on a downhill can overheat brakes.
Especially if you drag on them, which is not how you're supposed to brake.
Hey, fellers! :)
Those Maximas tho :drool:
They are very good.
i knew i shouldnt of let my friends dad bleed my brakes he threw shimano oil all over my brand new disc and brakepads now i need to change that
I thought Park Tool was pretty good until their simple little allen wrench set fell apart.
47 second mark he stuttered
Why the hell did bike companies foist these ridiculous devices on us? Rim brakes aren't prone to a tenth of the problems and they're just as effective.
My bike is just like my car, it slowly bleeds by itself and I have to top it off afew months
Are there any hydraulic leaks? (I suspect there are, I've never heard of any hydraulic brake line requiring bleeding this frequently)
If they work well, I leave them alone. If they don't work well, I buy a new bike.
You should never have to bleed your brakes, a push bike is meant to be a simple mechanism that can be worked on with basic simple tools, and anyone that thinks disc brakes make u stop in a shorter distance needs to go back and learn grade 10 physics
never bleed brakes, either run mechanicals or make enough money to have a tech do it, the juice isnt worth the squeeze.
Hydraulic brakes are a ridiculous gimmick, nothing else.
When Bob says so
Hi Calvin!