HOW TO FIX A LEAKING SHIMANO BRAKE LEVER

This video shows how to fix leaking problem on a M9000 brake lever, the problem is the piston inside, I am pretty sure most if not all shimano brake levers use the same piston, I am pretty sure this will work on m7000 m8000 m9000 and m785 series as well but I am not totally sure on the m7100 m8100 and m9100 series, they are the newest series and I cannot find info on the piston size but I heard they use different sizes so those new versions would probably need a different o-ring size
Getting to the piston is a little different with Shimano Servo Wave levers, here are a couple of links showing how to disassemble and reassemble them, they are not the clearest but they are the best I could find, will also link a short which has good picture quality of the inside
• Shimano Deore XT M8000...
• STUCK LEVER PISTON RE...
• Shimano XT M8000 Lever...
• When a SHIMANO Brake L...
Here are the links for the two different orings, first link choose 10x5x2.5mm , second link choose 9x5x2mm
They are from the same seller so you should save a little on shipping of buying both from them at same time in shopping cart
(10x5x2.5mm)
vi.aliexpress.com/item/100500...
(9x5x2mm)
www.aliexpress.com/item/10050...
Music Credit
Artist(s): Filo Starquez
Track: The Shack
/ @filostarquez
Mineral Oil
Seals
Pads
Piston
Plunger
Clip
Bleed
DIY Do It Yourself
Guide
Air
www.buymeacoffee.com/frobo64v

[@David_Wiebe]

Used this method on my Saint M820 lever. Disassembly was slightly different; there's a small metal pin you have to hammer out which was the hardest part for me. I first used both o-rings like you did, but the spring would not push the piston all the way out. Using just the larger o-ring allowed the piston to move properly. I've had 2 rides with this setup, about 5-6 hours total, brakes are feeling so good and no leaking so far. Thanks for the video :)

[@MTBfixHQ]

Hmmm im surprised the second o-ring affects your setup like that, its possible the plunger/piston is designed slightly different for each model, at least the main big o-ring is doing its job :) 👍 Cheers

[@artekh9435]

Same here on M520

[@ErnoTokesLive]

@@artekh9435 1 or 2 o-rings? I'm trying to solve it on my 520

[@artekh9435]

@@ErnoTokesLive i used 1 o-ring, both were too tight, working for a while

[@ErnoTokesLive]

Thanks ​@@artekh9435

[@renaldolr4811]

This is really helpful! Great explanation, high production quality and organized links. Well done man!

[@MTBfixHQ]

Thanks for the kind words! I try to make it as clear as I can :)

[@SlyDonkey]

Nice! Thanks for this!

[@MTBfixHQ]

Glad to help :)

[@stevewestpalm]

Will this work on low end Mt 200? Great instructions!

[@armanrivera4116]

thanks! really helpful

[@MTBfixHQ]

You are welcome :)

[@lostsoultheunforgiving7904]

I have emmo oxe e bike which has missing part on both sides of brakes ...how do I know what brakes to order ...there no name or part number ? I can show you what part I'm.missing if your interested in helping me

[@ThinkBlack1102]

Hey, nice work out there! I want to try this on my m820, both are leaking oil. Can I get you contact? I would like to get in touch with you.

[@AntiDEDok]

Bro, how long experience do you have with that setup? Does it affect lever feel?

[@MTBfixHQ]

I have used this setup for 2 years now on my other lever without issues, no difference in lever feel but if you use a oring that is too large it can affect the return speed of the lever because the return spring only has so much force

[@unknownuser39999]

This o-ring should be FKM material or it doesn't matter?

[@MTBfixHQ]

from my experience when I tried cheap black o-rings that came in my big cheap o-ring kit they didn't last as long as these brown FKM ones I ordered, FKM shouldn't matter I think it mostly comes down to the quality of the o-ring but it is possible the FKM o-rings keep their size better in the mineral oil

[@unknownuser39999]

@@MTBfixHQ I mostly find NBR material in my country. And I don't want to try many o-rings cause I have m820 brakes and they're pain to remove that pin if you know what I'm talking about. You believe NBR material is fine?

[@moontagelwl6207]

My m820 lever leaks air when I use the lever very slowly and it goes all the way to the handlebars without breaking unless I pull the lever fast. What should I do?

[@MTBfixHQ]

leaks air? there should be no air in the system, attach a funnel with some fluid and top off the system, if its still doing the same thing it sounds like maybe your seals on the piston are possibly worn out, I am guessing this because when you pull fast it puts enough pressure on the seal to expand and do its job, but if you go slow it wont expand enough to seal. I am not 100% sure these fit your model but I imagine they do www.aliexpress.com/item/1005002456932338.html

[@moontagelwl6207]

@@MTBfixHQ that should be the issue, I’ve already replaced the piston but the one I’ve installed was used from a brake whose lever was broken and I think the piston wasn’t new enough, thanks for the link I’ll try to get a new piston. Btw it’s a shigura mt5

[@JLneonhug]

Ahh this video and comment is a godsend. Really random but I have the same issue on a Zoom 876e. I suspected it's some sort of valve/rubber issue as at fast pressure it hooks up fine. I'll take it apart and have a look see. Thanks!

[@moontagelwl6207]

@@JLneonhug the issue was very easy to fix, take the lever piston out and change the rubber parts from the piston

[@marioxphoto703]

mines leaking at connection of the brake hose

[@MTBfixHQ]

sometimes tightening the nut with wrench can fix the leak

[@fra93ilgrande]

This is a Shimano XTR M9000, but I have the M9100 😅

[@maciejcieslik4626]

Hi, would be working with SLX m675?

[@MTBfixHQ]

from my understanding it should work

[@vincelegaspi7369]

Can you do this on xtr m9120?

[@MTBfixHQ]

Hi, yes it should work with all M6000-M9000 series brakes, cheers

[@zoranpl]

Shimano 9120, like the vast majority of Shimano brakes, has a servo wave system, so there are several plastic parts before the piston, which should be carefully disassembled so as not to break.

[@thispinguincoldashell]

Hello, will this work on a deore bl-m6100?

[@MTBfixHQ]

Hi, Yes it should use the same piston, Cheers

[@thispinguincoldashell]

​@@MTBfixHQThanks!

[@SubversionGarage]

Excellent tutorial! The 9000 series levers apparently use a slightly different sized piston. You can view this user's experience here kzbin.info/www/bejne/r6CreWqni5iXf8U

[@MTBfixHQ]

Thanks for letting me know! I made a mistake in my description by saying it works with m9100, I actually meant m9020, cheers

[@handsome_man69]

F*** that. I'm bringing my bike to a mechanic