Magura MT5 bleeding nightmare

I had to cut the hose, thread it through my frame and shorten it to fit my bike and the brake needed bleeding.

Bought a bleed kit from an eBay seller and watched a few vids so had an idea on what to do.

What a nightmare. At the moment I’m down half a bottle of magura brake fluid and have no brake.

I’ve tried the push and pull technique but air was getting in somewhere as there was tons of air bubbles appearing on the pull stroke.

Then I tried to gravity bleed and that is no good either.

My lever now comes straight to the bar and will eventually pump up after loads of lever pressed.

Any ideas on what I’ve done wrong.

Syndicate gravity bleed followed up by a lever bubble bleed has generally worked for mine.
Pads removed, bleed blocks in.

I’m down half a bottle of magura brake fluid

Is it leaking out somewhere? Unless it’s leaking you shouldn’t have lost any fluid beyond a few ml here and there.

Usually they bleed just fine, is your to “syringe” pushed in to the lever properly? Is the lever position correct (not the obvious position, that doesn’t work)

Hi.

I angled the lever up as per the description.

I lost a lot fluid due to trying a gravity bleed.

I found that pushing the fluid went ok but pulling it back seemed to introduce air into the system. I made sure the brass fitting was tight into the caliper but it still weeped around it.

I even tried taking the caliper off its mount and let it dangle.

No joy.

https://www.magura.com/media/1870/how_to_reroute_and_shorten_the_hose_techtip_1_may2012_01.pdf

Sometime when you pull you get air coming in from the connection between the rubber tube and the brass fitting especially if the syringe is held 90 degrees to the fitting. It can give the impression air is still in the system.

What would happen if I just did a push bleed to the lever from the caliper.

Would that work ?

Did you de-gas the fluid before bleeding. My old Avids always mentioned this and it was amazing how much air came out of the fluid.
Not sure on the technique you are using, but if pulling on the syringe while the system is closed you’ll probably see air forming in the syringe.
Won’t apply if you are pulling fluid through the system from one end to the other…
If you are down half a bottle, then you are either losing a noticeable amount of fluid, or that’s how much it took to refill the system.

Not sure what the magura bleed peocess is but I’ve never got all the syringe malarkey. For my Shimanos I just take the pads out, pull the caliper off the bike, pop in some bleed blocks, pop the hopper doofer in the lever, level the lever, open the bleed port and let gravity do the bleed. Then just nip up the bleed port, pull the lever back to the bar a few times until no more bubbles come out. I guess you could speed it up by opening the bleed port, pulling the lever, closing the bleed port and releasing the lever, just like you’d do for a car.

All sorted !!

I copied what the chap has done in the video above and put a small hole in the lever syringe.

It seemed to create a better vaccum this way.

I also popped the front end a big higher by sticking the front wheel on a patio chair.

Nice solid lever now.

Cheers all.

That was emotional.

I made sure the brass fitting was tight into the caliper but it still weeped around it.

This is likely part of your problem, the lever syringe just pokes in, no thread, no brass doobery, just push fit. You’ll likely chew the o ring and thread in the lever which will stop it sealing.

The only one to screw on should be the caliper.

Also when you gravity bleeding, use the syringe with the hole and the screw in tube at the calliper, use cable ties to hold it upright and just pump the fluid into that.

Any tips for bleeding?

Made a mess of shorting front hose so bought the total bleed solutions kit and have followed the above video to the letter and also tried using threaded adaptor at lever end but still can’t get a good lever

I don’t know if it helped but I put my front wheel on a chair and the let the brake dangle down so the lever was the highest point.

I also did the bit in the video where he put a small hole in the syringe as that gave more vaccum to suck the fluid through.

On my MT5s I just remove the plunger from the handlebar end syringe, so essentially just an open container for the oil to fill.

Fill bottom syringe full and attach to caliper
Remove lever screw and firmly push the syringe end into the lever. There is no way of knowing that it is correctly inserted, but I have never managed to insert it wrong!

Push fluid from bottom to top applying a fair amount of pressure, tapping hoses/caliper while doing so. When bottom is nearly empty or top syringe nearly full, pull back on bottom syringe slowly, much slower than you pushed it through. I don’t know exactly why, but my guess is that the top syringe does not make a good enough seal to create a proper vacuum, allowing air to creep in around the syringe.

Repeat until 1 more time after the last time you see bubbles in the top syringe. Finish on a push leaving a small amount in the bottom syringe. Insert plunger into the top of the top syringe.

Holding a rag to mop up spills quickly remove top syringe and insert plug, warning it’s extremely fragile literally just finger tight on the round part of the torx key don’t even try to snug it down tight.

Rotate bike in stand or lift caliper so it is higher than lever with filling port facing up. Remove syringe and fit port plug, from memory this one is less fragile.

If a bleed on new brakes i put the oil from top syringe back in bottle, if on old brakes I dispose of it.

This is just how I do it, run mt5 on two bikes now for a few years.