Magura MT Bleeding

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Magura MT Bleeding
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Posted: Jan 4, 2016 at 15:19 Quote
Hey guys,

So I just bought the Magura MT5 4 piston brake but i ca'nt figured out how to bleed them.
I tryed the owner manual way, every single how to video's, but i can't get it done.

I found on the magura forum http://www.support-english.magura.com/
a different way, but still got this changing pressure point when i'm riding.

So my last chance is between your hands oh dear Pinkbike community,Salute
Is anybody figured out a clear way to do it ?

Here the best how to i found but still not perfect :



New MT8 Brake Bleeding/Filling for Ultimate Lever Firmness UPDATED 7/11/12 STEP 13 NEW MASTER BLOCK 5/16 Allen wrench ~ .3125 thickness


… From a rider like you… I wasn't happy with the Magura bleed instruction result, long lever travel, less firm lever feel...This New procedure is just from a rider wanting a shorter lever travel, with more lever firmness...follow the procedure to the T and YOU WILL HAVE A SHORTER LEVER TRAVEL WITH A FIRMER BRAKE LEVER.

I ‘m going to do this back A$$ Backwards according per Magura instructions, but you will have the best d*m braking and lever feel on the planet! It really brings the life out of the MT8...this is what we wanted in the first place...so here is a little help to just do that...

Items needed: Magura basic syringe Bleed Kit with the two syringes and Royal Blood, Bike work stand, transport device and some shop rags.

Let’s get started: basically this set up is for the rear brake bleed, but also same method applies to the front.

1. First, put the bike in the bike stand

2. Second, take the rear brake lever, line and caliper assemble completely off the bike working on the rear brakes everything off

3. Third, now that the bike is in the stand with the rear brake off, tilt the bike in the stand with the front fork up in the air at a 45 degree angle, next rotate the handle bar and front wheel 180 degrees, so that the brake lever when mounted back on the handle bar will be pointing towards the rear of bike This helps with two things here keeps the front wheel from flopping side to side, second, will take most of the bend out of the brake line, less trapped air.

4. Prepare caliper for bleeding with transport device. Per Magura

5. Fully retract caliper pistons, by pushing them back in with transport device

6. Remove the brake pads to avoid contaminating them with oil. IMPORTANT NEW STEP I had encountered a problem while removing the brake reservoir handle bar clamps, when the brakes were first removed from the new Magura Box, while removing the clamps, as I had loosed the T25 nuts, the studs would start to back out of the carbon body, I think this may be why some people including myself had an ongoing spongy lever, you may not know this, the reservoir cap is actually the red plastic between the reservoir and handle bar, the studs hold the reservoir cap on, a loose stud would let air in the system, …So with that said, put some electrical tape on the studs that hold the bar clamps and tighten with some pliers, lightly not to damage the threads, remove tape. This is a must do step.

7. Now mount the rear brake lever back on the handle bar with the rear brake lever facing the rear brake mount, Tilt the rear lever master assemble at the 15 degree angle and tighten lightly, install the transport block between the caliper pistons and secure, rubber band or electrical tape, let the line and rear brake caliper hang down straight to the floor, keeping the caliper off the floor, with no bends in the brake line, you may have to raise the bike in the stand, had my stand all the up, so the brake line would hang with no bends.

8. Now fill a syringe with Magura brake fluid for the rear brake caliper, hold the caliper to the height of the rear brake lever on the handle bar or just slightly above, open the caliper bleed screw, no fluid should leak out, attach the syringe, and tighten with a 8mm wrench.

9. Open the T25 air bleed screw on the handle bar brake reservoir, install the second syringe, the second syringe is being used as a open reservoir with the plunger out of the syringe, press syringe tip firmly into reservoir, but don’t overdo it, Pour about 5ml of Magura brake fluid into syringe.

10. Now let’s get this bleeding started, now keeping the brake line straight down with the caliper near the floor, push the fluid into the system, A firm somewhat of a fast push, leave about 5ml of fluid in bottom syringe, don’t push it all out, this avoids putting any air back into the system with several push and pulls.

11. Now with the brake line straight down with the caliper near the floor, pull the fluid back into the syringe, kind of a fast pull at first, this will create a pocket of vacuum looks like an air space, then let up some, but still pulling. This will pull the air out of the line. Then repeat the push and pulls can’t give you an exact number of push/pull, for me it was about 10 push pulls. I would wait a few minutes between push/pulls, I could see micro bubbles still heading to the top...I had to push kind of fast and hard to get the air bubbles to move out, could hear them bubble out the top syringe reservoir.

12. Now let’s get this bleed buttoned back up. I ‘m going to do this back A$$ Backwards according Magura instructions, but you will have the best d*m braking and lever feel on the planet what I had noticed in the Magura basic bleed kit bleeding procedure with the two syringes, As I pulled the fluid back into the lower brake caliper syringe, the pulling of the syringe would also retract the caliper pistons away from the transport device, sometimes sticking in the caliper, creating a gap… resulting in more lever travel..How to fix this gap, sticky caliper piston, shorten excessive lever travel, and have the best d*m braking and lever travel in the world, next step.

13. First, place about 5ml of Magura blood in the top reservoir; second, make sure each caliper piston moves freely in and out of the brake caliper. Here is how: remove the transport device, and place a 5/16 Allen wrench parallel (5/16 ~ .3125 now being used as the desired master block) between the caliper pistons while holding the Allen wrench at one end with your index finger and the other end of the Allen wrench with your pinky finger, pulling or holding one caliper piston flush against the caliper with the 5/16 Allen. Now push Magura blood from the bottom brake caliper syringe into the brake system, one piston held tight against the caliper with the Allen wrench the other caliper piston will move out of the caliper against the other side of the Allen wrench when the fluid is pushed in the system from the bottom caliper with a syringe, great...with one piston halfway out and one piston now flush to the brake caliper, time to clean the piston that is hallway out with a Q tip and with some Magura oil, remove any grime or dirt off the caliper piston O.D. And lubricate around the piston O.D. with some Magura oil. Now push the caliper piston that is halfway out back into the caliper with the Allen wrench, so that the Allen wrench and caliper piston is flush to the caliper, Now do the same procedure to the other caliper piston, Hold the cleaned caliper piston flush against the caliper with the 5/16 Allen wrench, Push More fluid into the system from the lower brake caliper syringe, so that the other side caliper piston moves out, clean and lubricate....if a sticky caliper piston persist, may half to do the Allen side to side procedure more than once. IMPORTANT, we now want the 5/16 Allen wrench and caliper pistons balanced, push the last cleaned piston back in the caliper some, and push more fluid into the brake system to move the other piston out against the Allen wrench.

14. With 5/16 Allen wrench between the caliper pistons and centered between them, remove the 5/16 Allen, raise the rear brake caliper to the height of the handle bar rear brake lever, or just slightly above, while holding at the handle bar height, remove caliper syringe, put in bleed screw, tighten. Almost done Next Step.

15. Now the top syringe reservoir may have a large amount of brake fluid in it, from pushing out the pistons that’s ok. Since the bottom caliper is already buttoned up, no fluid can leave the system, remove the top, syringe, while placing your finger on the syringe tip, holding any fluid from spilling and replace the plastic bleed plug. Place any remaining fluid in container.

16. Great …now remove entire brake lever assembly, and clean with soap and water, a soapy paper towel will work to remove any brake fluid from the brake lever, piston caliper, and then rinse.

17. With everything clean and buttoned up, reinstall the brake pads, if pads are a little tight, can push back the brake pads with the thinnest part of the transport device…. This is what we want, only the thickness of the thinnest part of the transport should fit between the now installed brake pads, this is about .084 thousands of an inch, now with the thinnest part of the transport device installed and secured, go ahead and squeeze, pump the lever, several times, should be a rock solid lever, with a lot less lever travel per Magura instructions. Note: when installing the brake caliper and now installed pads over the rotor, everything should look centered, brake pad ears, same amount on each side, caliper piston contact against brake pads, same amount, each caliper piston should be moved out of caliper housing slightly with the new bleed procedure, with the brake lever at a reseting positon, no lever engagement. Each brake pad ear should have a equal small amount of movement (wiggle), on each side on the brake caliper guide pin when the brake lever is squeezed, indicating the caliper pistons have free movement and working correctly.

18. Reinstall brake assembly onto bike… Have an Awesome Day

O+ FL
Posted: Mar 25, 2019 at 6:33 Quote
I came across this old thread while looking for information on how to bleed my MT5 brakeset after a series of unsuccesful attempts. It worked perfectly. I believe Step 6 is not applicable to MT5 or MT7.

Removing calipers from brake mount and letting them hang down was key to removing all air pockets. Tilting brake levers up 15deg also may have helped.

Posted: Mar 25, 2019 at 12:27 Quote
Agree with what the last poster said.
Also, I don't do the push pull from each end as magura recommends. I just push from the caliper end whilst tapping the caliper, brake lines where required ie bends etc and finally give the lever a few pulls and then push more fluid to dislodge any air trapped in master cylinder.

I found pushing fluid back from lever end just introduced air into the system. It may feel ok on the stand but once ridden the lever turned to crap.

Posted: May 30, 2020 at 20:05 Quote
I've also been struggling with a set of Magura MT Trails. I've got the front brake pretty good, bite point ok-ish and strong enough but the rear is getting the best of me.

I've tried the usual Magura bleeding way, I've tried the one mentioned above, no matter how I do it, I just can't get it working properly. The bite point is almost at the bars and there's no way I can even get close to locking up the rear.

I really want to love these brakes but I'm getting close to just giving up, selling them and get another brand. To be honest, I don't know if I would prefer these Maguras if I get them working, with lots of modulation or something Shimano like with the on-off feeling.

All in all, I'm wasting way more riding time on tinkering with these than I should...

Posted: May 30, 2020 at 22:21 Quote
I have to bleed a set of maguras for the first time in the next few days and am hoping they won't prove to be a problem.

I always found with my shimano brakes that I needed to unbolt the caliper from the frame and manipulate it up/down/left/right to get the air bubbles out of the caliper. Then I would seal the caliper (different (better) system where you just close the bleed port), and give a bunch of squeezes of the lever to get the rest of the bubbles out of the master. It is really important when doing this that you raise the front end of the bike significantly. Having a bike stand helps.

On the Maguras I plan on doing the push from the bottom with no plunger in the top syringe. Of course you need the pads removed and some sort of bleed block in place so you can squeeze the lever. Manipulate the caliper around to release any bubbles at the caliper while push/pulling gently from the bottom. Then squeezing the lever a bunch of times to get any bubbles out of the master. I think I'm going to try to not seal the top syringe and just pull it out really quick and sealing it off with my thumb while making a small mess. I am going to miss the shimano reservoir with the plug for this purpose. Then you can seal the master, unscrew the bleed adapter at the caliper and put the plug back in.

One issue I find is that a bleed block usually has the pistons farther in that they would be during normal use, and that once you seal off the master it doesn't want to take up the slack. To solve this what I may try is after bleeding the system, cleaning everything and fully reinstalling the caliper with the pads. Then opening the master screw back up, putting the reservoir back in with a tiny bit of fluid and no plunger, and giving some lever flicks so that the pistons can use up any travel to get it back in their normal position. WARNING: this means that this system will be basically overfilled and that it would be impossible to force the pistons all the way back in. If you did it this way with worn pads, when you replaced the pads and needed to push the pistons back in you would need to open the system for this to be possible.

Hopefully that sounds slightly different than your method and is worth a try. You definitely have a pile of air in your brake lines. Hopefully that also works and I don't have any problems when I go to do it in a few days lol.

Posted: May 30, 2020 at 23:40 Quote
From a well established member with way more experience than me. Good luck.

"Level the lever.
• Fill the syringe with the caliper adapter full of fluid. Remove all bubbles.
• Put a little fluid in the syringe for the lever. Just a little. Remove all bubbles.
• Doesn't really matter which end you start at. I like to start at the lever because there will be a surplus of fluid available when a little drips out at the caliper.
• Open the port at the lever and stab in the syringe (mine has a taper on the end that wedges in there nicely). You may want to be gently pressing the plunger as you stab it in to ensure a bubble hasn't formed at the tip.
• Open the port at the caliper and thread in the syringe and adapter. I use a drill to get the screw out a few seconds faster.
• You now have both ends connected. Start pushing at the caliper end and occasionally switch to a mild pull at the lever end. When pulling, give a gentle push at the caliper end so you don't pull a crazy strong vacuum.
• Exchange fluid back and forth several times with the push & pull technique.
• Finish with the lever syringe full and the caliper syringe almost empty. If the syringes are large enough, this will have fully replaced your fluid.
• Remove the caliper end. Again, I have the screw already loaded on my drill when I unscrew the adapter. I use the minimum torque setting on the drill, which, with the inertia of the drill, tightens almost perfectly.
• Remove the lever end. Replace the plastic screw very gently. That thing strips out so easily.
• Level the lever.

I once had to do it maybe four times to get a good bleed, but that was before I learned the trick of pushing and pulling the fluid; since then it's usually one or two attempts."

O+
Posted: May 31, 2020 at 6:26 Quote
One thing I have found is you need to move the fluid through slowly. And I have seen a dozen posts about pushing fluid or pulling from the lever side of the system, but I don’t believe the seal at the lever port is sufficient to push fluid. I highly recommend (and so does Magura) to only push and pull from the caliper side where you have a mechanical seal.

I had trouble at first but simply using the method in the Magura support videos of always pushing fluid/pulling from caliper end and when pushing fluid the lever should be the high point, when pulling fluid through the caliper, the caliper should now be the high point, it’s also key to manipulate the height of the caliper when sealing off the system to not introduce air. This is a good video on the process.

https://m.youtube.com/watch?v=Fbb8G3TCNug




Posted: May 31, 2020 at 9:26 Quote
Branmuffin wrote:
, it’s also key to manipulate the height of the caliper when sealing off the system to not introduce air
all great advice. The only problem with this is it's practically impossible to do if you have internal rear brake routing. I found one video where the Master seal was secure enough that removing the caliper screw did not release any fluid and another where fluid came pouring everywhere even with the master screw back in. Makes me wonder if the master screw even fully seals the master

O+
Posted: May 31, 2020 at 9:32 Quote
friendlyfoe wrote:
Branmuffin wrote:
, it’s also key to manipulate the height of the caliper when sealing off the system to not introduce air
all great advice. The only problem with this is it's practically impossible to do if you have internal rear brake routing. I found one video where the Master seal was secure enough that removing the caliper screw did not release any fluid and another where fluid came pouring everywhere even with the master screw back in. Makes me wonder if the master screw even fully seals the master

It does make it more difficult but if needed you can feed extra hose from the front of the bike to the back for the bleeding process and also manipulate the angle of the bike on the work stand.

Posted: May 31, 2020 at 9:43 Quote
Branmuffin wrote:
friendlyfoe wrote:
Branmuffin wrote:
, it’s also key to manipulate the height of the caliper when sealing off the system to not introduce air
all great advice. The only problem with this is it's practically impossible to do if you have internal rear brake routing. I found one video where the Master seal was secure enough that removing the caliper screw did not release any fluid and another where fluid came pouring everywhere even with the master screw back in. Makes me wonder if the master screw even fully seals the master

It does make it more difficult but if needed you can feed extra hose from the front of the bike to the back for the bleeding process and also manipulate the angle of the bike on the work stand.

I was thinking about spinning the bike in the stand after sealing off the master. Pretty sure I'm going to need a second set of hands to do it but can probably make that happen

O+
Posted: May 31, 2020 at 9:47 Quote
friendlyfoe wrote:
Branmuffin wrote:
friendlyfoe wrote:
all great advice. The only problem with this is it's practically impossible to do if you have internal rear brake routing. I found one video where the Master seal was secure enough that removing the caliper screw did not release any fluid and another where fluid came pouring everywhere even with the master screw back in. Makes me wonder if the master screw even fully seals the master

It does make it more difficult but if needed you can feed extra hose from the front of the bike to the back for the bleeding process and also manipulate the angle of the bike on the work stand.

I was thinking about spinning the bike in the stand after sealing off the master. Pretty sure I'm going to need a second set of hands to do it but can probably make that happen

I have a pretty crapy bike stand, like $45 and mostly plastic. If i take the wheels off front and back it is able to hold my bike at a 45 degree angle pretty easily but it can be tricky. Especially if your stand does not have a clamp or a lock.

Posted: May 31, 2020 at 19:36 Quote
Good news! Finally I've got these damn brakes working. They're properly brutal, no wonder I see them used on trials bikes too. A couple notes which may help anyone struggling:

- while pushing the caliper syringe, I changed the lever angle a few times. This helped a lot, noticed huge bubbles.
- similarly, while pushing, I kept moving around the caliper, this also helped dislodge stubborn bubbles.
- I used thinner bleed blocks. 8mm vs 10mm stock ones - this may be very important to get better bite point.

Otherwise I pretty much followed the procedure (with open syringe stuck in the lever), push/pull about 8 times until no more bubbles.

Small rant on Magura design: the MT5 caliper is exactly the same as MT Trail for example, except for the pads. Instead of 4 small pads, they have 2 sort of double pads. This is incredibly stupid and the pad backplate with the little hooks to keep them in place, makes it extremely difficult to put them in when the pistons are even a little bit out. Also to remove them, the caliper must be removed. I can't understand what were they thinking when they came up with this. I have the MT Trail 4 piston caliper on the front so I know what I'm talking about.

photo

Speaking of bike stand, one 2x4 and a little time. It's strong and I can place the bike in multiple positions.

photo

Posted: Jun 1, 2020 at 11:00 Quote
cucupebicicleta wrote:
I used thinner bleed blocks. 8mm vs 10mm stock ones - this may be very important to get better bite point.

So I'll just mention this again since a lot of information was posted above. I came up with a solution to this problem.
-go through the procedure as described, fully clean and reassemble the caliper with pads and wheel in place, bolt everything back up
-reopen the master cylinder and put the reservoir back in with a small amount of fluid
-Give the brake lever a bunch of squeezes

Doing this extra step allows the system to take in just enough extra fluid for the pistons to take up the gap between being fully retracted and the pad. You have to be aware though that this means the system is overfilled and it will not be possible to push the pads all the way back into the caliper without doing damage. So if you did this with worn pads and put new ones in you would probably need to do this simple process, open the master with the reservoir in place, before pushing the pistons back to insert new pads.

The only other thing is this is really easy with shimano brakes as the reservoir has a plug so little to no fluid leaks out. Doing it on the Magura's is going to be a bit messier so it would be worth zip tieing a rag to the brake hose so fluid doesn't leak down.

Posted: Jun 1, 2020 at 12:37 Quote
friendlyfoe wrote:

So I'll just mention this again since a lot of information was posted above. I came up with a solution to this problem.
-go through the procedure as described, fully clean and reassemble the caliper with pads and wheel in place, bolt everything back up
-reopen the master cylinder and put the reservoir back in with a small amount of fluid
-Give the brake lever a bunch of squeezes


Good point. As you mentioned, the end result is basically the same - getting a little more fluid in the system to keep the pads closer to the disc. It's still strange the we must do this to get them to work.

For now I'm just very happy these things actually can work so well but I will take points off for having to "improvise" with the bleeding procedure. To be completely honest, while I love how strong these are now, if I were to start over, I'd probably avoid Magura. I worked on shimano brakes too and they're way easier to set up, mess free and just work.

O+
Posted: Jun 1, 2020 at 13:05 Quote
cucupebicicleta wrote:
friendlyfoe wrote:

So I'll just mention this again since a lot of information was posted above. I came up with a solution to this problem.
-go through the procedure as described, fully clean and reassemble the caliper with pads and wheel in place, bolt everything back up
-reopen the master cylinder and put the reservoir back in with a small amount of fluid
-Give the brake lever a bunch of squeezes


Good point. As you mentioned, the end result is basically the same - getting a little more fluid in the system to keep the pads closer to the disc. It's still strange the we must do this to get them to work.

For now I'm just very happy these things actually can work so well but I will take points off for having to "improvise" with the bleeding procedure. To be completely honest, while I love how strong these are now, if I were to start over, I'd probably avoid Magura. I worked on shimano brakes too and they're way easier to set up, mess free and just work.

You don’t have to improvise the bleeding process. The standard bleed blocks work perfectly fine.

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