I've had the Birzman Disc Brake Piston Pusher for some years now, and after seeing so many cracked Shimano pistons now I am never touching my M8120 pistons with anything else than that tool. It delivers an equal pressure on the piston(s) on both sides at the same time. I don't care how careful some people claim to be, there must be a connection from using tire levers and so on and the cracked pistons. I at least will place my bet on the handling of the pistons, rather than the pistons just shattering from normal operation. The other great thing is I do not need to remove my wheels to adjust pistons(only works on top loaded calipers though), only pop out the pads, and I can go to town. I highly recommend that tool. A real peace of mind.
Thanks for the tip. I Didn't know the tool existed. I have to agree with your point though. I stopped using the metal park tool brake pusher and have only been using plastics tires levers lately, so far so good, but this tool makes much more sense. 👍
finally found a break down on same calipers i have. 1 of my pistons is very stiff i got some new seals but when i try to separate them it was not budging and i could not find a vid until this. now i have confidence splitting the caliper in the right way i was struggling to split them i thought i was going to break or do damage. absolute love the breaks i fly around London roads and could not ride the way i do without them. i use the Race version . thanks fore the upload. subbed UK
Glad you found the video helpful. The calipers look somewhat intimidating when trying to seperate it. Just make sure to seperate it as evenly as possible on both sides. 👍
lol loved this video, it was the twist at the end that did it. I suspect I broke a piston today, ordered the caliper because I wasn't able to find a kit, then I found a kit and this video...and now I'm just going to go ahead with the new caliper. Appreciate your struggle sir, sorry it didn't work out!
Great vid buddy. Front slx brake exploded last week. Cracked a piston somehow. I only use plastic tyre levers to reset them so maybe already faulty? Anyway, thanks. Saved me a few quid.
I'm glad to hear it was of some use to you. Sorry to hear about your piston cracking. It really sucks that Shimano doesn't sell replacement parts for their brakes. I still haven't come across a replacement solution that actually works. If I do, I will definitely let people know
I had a shop crack one of my Shimano pistons while it was in for service. Got home with the bike and the lever went right to the bar. I went back to the shop and they wanted to tell me it wasn’t their fault. I basically forced them to pull a brake off an ebike on the floor and install it for free. Unfortunately it was a downgrade to a deore 2 pot but they don’t have ceramic pistons so they should be more reliable. Back to back I prefer the feel of Shimano ceramic pistons.
sorry to hear that. you would think they would have swapped the caliper with the same model. its total BS that shimano doesn't sell the pistons (imo) but they do sell just the caliper, which the shop could have purchased
@@zoubtube they told me it was going to be over a month for them to get just the caliper (crazy because I could have gotten one from jenson USA in 2 days). If they had to install the caliper and do a bleed they would of had my bike for another few days. Thankfully, I didn’t have to pay for their mistake. Needless to say, I do all my own bike service now. And honestly, after trying the sram guide I’m convinced my next bike will have them. They are very good and much more serviceable than the Shimano equivalent.
@@BrandonMeyer1641 "they told me it was going to be over a month for them to get just the caliper" Geez, and here I thought supply chain was easing up. "And honestly, after trying the sram guide I’m convinced my next bike will have them" Though I like both SRAM and shimano brakes, I have to say when I swapped the stock pistons on the guides ultimate's for the metal aftermarket pistons back in 2017/2018, the feel has been excellent. super consistent in both summer and winter. I just don't see a reason to replace them yet. but then again, I'm in SE MI, we don't have any large descents around here where I would need more power. Highest hills are about 100ft vertical drop. As for my XTR's, they are basically on and off, Not ideal but I can live with for the XC bikes. But the wandering bite point is definitely real with shimano's, at times it's super annoying! "They are very good and much more serviceable than the Shimano equivalent." I believe that most shops want to do good by their customers, but brake jobs are definitely something I would prefer to do on my own. During the busy season the shops have to pump out bikes as fast as they can. I'd rather take a few extra minutes and make sure my brakes are perfectly bled. same goes for bleeding shocks and forks. one small air bubble makes a big difference in any hydraulic system. So if you have any questions on this stuff let me know!
Thanks for sharing your experiance with these aftermarket pistons. If something simular happens again, maybe you could order a lower tier shimano caliper like SLX and use this to source the replacement parts or use the SLX caliper straightaway. As far as I know there ist pretty little difference besides the paintjob in shimano calipers. Only the 12s Road Dura Ace has a monoblock construction rather the a two piece construction like ultegra and 105. Sometimes the piston material veries between between ceramic and resin for different tiers (e.g. GRX) and even though I couldnt find the piston material on the offical shimano side, on some sites from Online Retailers I found this information.
Thanks for watching. if you come across sure fire solution, PLEASE share it with everyone. 🙏 There are many people out there who would like to solve this for once and for all. it total BS that shimano doesn't offer these as spare parts
nice. i also have a broken piston, but can only find replacements on dodgy sites in china and on amazon its still half the price (incl shipping) of the price of the caliper...
Yup! it's frustrating that shimano doesn't sell replacement parts for their brakes. I haven't had luck with aftermarket pistons for their brakes. If you come across a solution that works feel free to let us know. it would be appreciated
I had a similar issue today. Cracked ceramic piston on a Shimano 8120 caliper. Mine was fresh out of the box and I found it on installation when I had a crap lever feel. (They supposedly come pre-bled as a kit) It was leaking directly from the inboard upper piston. I tried to push the pistons back evenly and cycled them a few times while lubing them with mineral oil. That one piston never retracted and it sounded like broken glass when I tried pushing it in. Took the caliper apart and found the same thing you demonstrated. I'm going to hopefully push a warranty claim on this, but thanks for a great video.
well that's sucks, especially new out of the box. If you bought them online, make sure to stay on top of the return process and don't let time lapse. I recently had to return a brand new set of atlas pedals, which race face confirmed had a manufacturing defect. The shop wouldn't process the return until raceface processed it with them first. Took about a month to complete. Not that I minded, just didn't realise it would take so long. All I wanted was a replacement , yet they ended up refunding the money (literally two days ago) and told me to buy them again. I guess I've been spoiled by lbs's and amazon 😉
I am using this same EXNAVI kit to hopefully repair a Shimano GRX 810 caliper. It’s really hard to imagine with the dimensions being so close to the originals that they didn’t work out. Any chance the square gland seals took some damage during reassembly? Also, one Amazon review mentioned the material may be melamine, which is pretty tough stuff. We’ll see…
They might work for you. The brake in the video is an M9000. I have no idea what manufacturing tolerances this brand goes by, but my guess is the tolerance was outside of the m9000 specs. I tried the original seals and the ones that came with the pistons. both leaked in my case when pressure was applied. Hopefully you have better luck than I did
@@pkananen From what I see, Shimano doesn't sell replacement pistons for the 810's either. bike.shimano.com/en-EU/product/component/grx-11-speed/BR-RX810-F.html. After market will be your only choice.
I was hoping they would work with the m9100's but they don't. they unfortunately kept leaking when pressed hard. I tried all sorts of permutations but they kept failing so I can't recommend them for this model brake. I ended up buying a new caliper. I can't speak to other model brakes they claim to work with though.
I had a leaky caliber on my Shimano caliper and used an Amazon replacement and it hasn’t leaked at all. I’ve braked very hard on high speed descents and it’s held up for over a year now.
Same way like in this video. you will have to separate the calipers.. To do this remove the two bolts. then you will need a strong tool that will help you start to separate the caliper sides. a piston press tool like I used in the video works well for this. Once they serrate a bit, SLOWLY pry them apart, alternating sides, with a flat head screw driver. once apart you will be able to install the pistons. You HAVE to make sure that they get pressed in as evenly as possible. if you feel like there is to much force, they aren't evenly inserting all around. When even, they will slip in with some force using your hands. then connect the caliper sides together reverse order as you separated them and install on the bike. hopefully this makes sense
They didn't 😁. At the end of the video I mentioned that the seals leaked during first use. Not sure if it was due to the seals or the Delrin pistons. I ended up retuning them and buying a caliper instead. definitely don't recommend the Delrin piston replacement kit
@@zoubtube That's a bummer. I have ordered some off ebay, not sure if they are the same China supplier. I will test with some plastic spacers and not pads then.
@@robertstewart7172 When installing them they seemed like they would work but they started leaking during the first ride. The pads were scrapped. I then tried switching between the seals that came with kit and the originals but it still leaked when testing them with the bleed block. It's possible your kit might work better, I don't know what the manufacturing tolerances are on these things. I would definitely test them harder and longer than I did with the bleed block before installing pads and riding them
I've had the Birzman Disc Brake Piston Pusher for some years now, and after seeing so many cracked Shimano pistons now I am never touching my M8120 pistons with anything else than that tool. It delivers an equal pressure on the piston(s) on both sides at the same time. I don't care how careful some people claim to be, there must be a connection from using tire levers and so on and the cracked pistons. I at least will place my bet on the handling of the pistons, rather than the pistons just shattering from normal operation.
The other great thing is I do not need to remove my wheels to adjust pistons(only works on top loaded calipers though), only pop out the pads, and I can go to town. I highly recommend that tool. A real peace of mind.
Thanks for the tip. I Didn't know the tool existed. I have to agree with your point though. I stopped using the metal park tool brake pusher and have only been using plastics tires levers lately, so far so good, but this tool makes much more sense. 👍
finally found a break down on same calipers i have. 1 of my pistons is very stiff i got some new seals but when i try to separate them it was not budging and i could not find a vid until this. now i have confidence splitting the caliper in the right way i was struggling to split them i thought i was going to break or do damage. absolute love the breaks i fly around London roads and could not ride the way i do without them. i use the Race version . thanks fore the upload. subbed UK
Glad you found the video helpful. The calipers look somewhat intimidating when trying to seperate it. Just make sure to seperate it as evenly as possible on both sides. 👍
lol loved this video, it was the twist at the end that did it. I suspect I broke a piston today, ordered the caliper because I wasn't able to find a kit, then I found a kit and this video...and now I'm just going to go ahead with the new caliper. Appreciate your struggle sir, sorry it didn't work out!
Good move imo. Shimano really should offer piston replacements like sram does.
Great vid buddy. Front slx brake exploded last week. Cracked a piston somehow. I only use plastic tyre levers to reset them so maybe already faulty? Anyway, thanks. Saved me a few quid.
I'm glad to hear it was of some use to you. Sorry to hear about your piston cracking. It really sucks that Shimano doesn't sell replacement parts for their brakes. I still haven't come across a replacement solution that actually works. If I do, I will definitely let people know
I had a shop crack one of my Shimano pistons while it was in for service. Got home with the bike and the lever went right to the bar. I went back to the shop and they wanted to tell me it wasn’t their fault. I basically forced them to pull a brake off an ebike on the floor and install it for free. Unfortunately it was a downgrade to a deore 2 pot but they don’t have ceramic pistons so they should be more reliable. Back to back I prefer the feel of Shimano ceramic pistons.
sorry to hear that. you would think they would have swapped the caliper with the same model. its total BS that shimano doesn't sell the pistons (imo) but they do sell just the caliper, which the shop could have purchased
@@zoubtube they told me it was going to be over a month for them to get just the caliper (crazy because I could have gotten one from jenson USA in 2 days). If they had to install the caliper and do a bleed they would of had my bike for another few days. Thankfully, I didn’t have to pay for their mistake. Needless to say, I do all my own bike service now.
And honestly, after trying the sram guide I’m convinced my next bike will have them. They are very good and much more serviceable than the Shimano equivalent.
@@BrandonMeyer1641
"they told me it was going to be over a month for them to get just the caliper"
Geez, and here I thought supply chain was easing up.
"And honestly, after trying the sram guide I’m convinced my next bike will have them"
Though I like both SRAM and shimano brakes, I have to say when I swapped the stock pistons on the guides ultimate's for the metal aftermarket pistons back in 2017/2018, the feel has been excellent. super consistent in both summer and winter. I just don't see a reason to replace them yet. but then again, I'm in SE MI, we don't have any large descents around here where I would need more power. Highest hills are about 100ft vertical drop. As for my XTR's, they are basically on and off, Not ideal but I can live with for the XC bikes. But the wandering bite point is definitely real with shimano's, at times it's super annoying!
"They are very good and much more serviceable than the Shimano equivalent."
I believe that most shops want to do good by their customers, but brake jobs are definitely something I would prefer to do on my own. During the busy season the shops have to pump out bikes as fast as they can. I'd rather take a few extra minutes and make sure my brakes are perfectly bled. same goes for bleeding shocks and forks. one small air bubble makes a big difference in any hydraulic system.
So if you have any questions on this stuff let me know!
Thanks for sharing your experiance with these aftermarket pistons. If something simular happens again, maybe you could order a lower tier shimano caliper like SLX and use this to source the replacement parts or use the SLX caliper straightaway. As far as I know there ist pretty little difference besides the paintjob in shimano calipers. Only the 12s Road Dura Ace has a monoblock construction rather the a two piece construction like ultegra and 105. Sometimes the piston material veries between between ceramic and resin for different tiers (e.g. GRX) and even though I couldnt find the piston material on the offical shimano side, on some sites from Online Retailers I found this information.
Thanks for watching. if you come across sure fire solution, PLEASE share it with everyone. 🙏 There are many people out there who would like to solve this for once and for all. it total BS that shimano doesn't offer these as spare parts
nice. i also have a broken piston, but can only find replacements on dodgy sites in china and on amazon its still half the price (incl shipping) of the price of the caliper...
Yup! it's frustrating that shimano doesn't sell replacement parts for their brakes. I haven't had luck with aftermarket pistons for their brakes. If you come across a solution that works feel free to let us know. it would be appreciated
I had a similar issue today. Cracked ceramic piston on a Shimano 8120 caliper.
Mine was fresh out of the box and I found it on installation when I had a crap lever feel. (They supposedly come pre-bled as a kit)
It was leaking directly from the inboard upper piston. I tried to push the pistons back evenly and cycled them a few times while lubing them with mineral oil. That one piston never retracted and it sounded like broken glass when I tried pushing it in.
Took the caliper apart and found the same thing you demonstrated.
I'm going to hopefully push a warranty claim on this, but thanks for a great video.
well that's sucks, especially new out of the box. If you bought them online, make sure to stay on top of the return process and don't let time lapse. I recently had to return a brand new set of atlas pedals, which race face confirmed had a manufacturing defect. The shop wouldn't process the return until raceface processed it with them first. Took about a month to complete. Not that I minded, just didn't realise it would take so long. All I wanted was a replacement , yet they ended up refunding the money (literally two days ago) and told me to buy them again. I guess I've been spoiled by lbs's and amazon 😉
I am using this same EXNAVI kit to hopefully repair a Shimano GRX 810 caliper. It’s really hard to imagine with the dimensions being so close to the originals that they didn’t work out. Any chance the square gland seals took some damage during reassembly? Also, one Amazon review mentioned the material may be melamine, which is pretty tough stuff. We’ll see…
They might work for you. The brake in the video is an M9000. I have no idea what manufacturing tolerances this brand goes by, but my guess is the tolerance was outside of the m9000 specs. I tried the original seals and the ones that came with the pistons. both leaked in my case when pressure was applied. Hopefully you have better luck than I did
I also have a busted GRX 810 piston.
@@pkananen Mine are still holding strong 3weeks later.
@@pkananen From what I see, Shimano doesn't sell replacement pistons for the 810's either. bike.shimano.com/en-EU/product/component/grx-11-speed/BR-RX810-F.html. After market will be your only choice.
Great video. How did these perform pushed hard?
I was hoping they would work with the m9100's but they don't. they unfortunately kept leaking when pressed hard. I tried all sorts of permutations but they kept failing so I can't recommend them for this model brake. I ended up buying a new caliper. I can't speak to other model brakes they claim to work with though.
I had a leaky caliber on my Shimano caliper and used an Amazon replacement and it hasn’t leaked at all. I’ve braked very hard on high speed descents and it’s held up for over a year now.
Shimano m615 Brake caliper piston popped out. How do I get it back in? :
Same way like in this video. you will have to separate the calipers.. To do this remove the two bolts. then you will need a strong tool that will help you start to separate the caliper sides. a piston press tool like I used in the video works well for this. Once they serrate a bit, SLOWLY pry them apart, alternating sides, with a flat head screw driver. once apart you will be able to install the pistons. You HAVE to make sure that they get pressed in as evenly as possible. if you feel like there is to much force, they aren't evenly inserting all around. When even, they will slip in with some force using your hands. then connect the caliper sides together reverse order as you separated them and install on the bike. hopefully this makes sense
And how did the new piston/seals go?
They didn't 😁. At the end of the video I mentioned that the seals leaked during first use. Not sure if it was due to the seals or the Delrin pistons. I ended up retuning them and buying a caliper instead. definitely don't recommend the Delrin piston replacement kit
@@zoubtube That's a bummer. I have ordered some off ebay, not sure if they are the same China supplier. I will test with some plastic spacers and not pads then.
@@robertstewart7172 When installing them they seemed like they would work but they started leaking during the first ride. The pads were scrapped. I then tried switching between the seals that came with kit and the originals but it still leaked when testing them with the bleed block. It's possible your kit might work better, I don't know what the manufacturing tolerances are on these things. I would definitely test them harder and longer than I did with the bleed block before installing pads and riding them
Thank you for a bullshit-free presentation.