[manhattanprjkt83]

Has anyone done this? It was a total idiot move on my part but a bit cracked off and moved the seal so fluid started dripping out. I ordered some 3rd party piston which arrived yesterday. Any tips on the replacement process? This is an XTR 4 piston for reference...Thanks guys...

 

[kidwoo]

Has anyone done this? It was a total idiot move on my part but a bit cracked off and moved the seal so fluid started dripping out. I ordered some 3rd party piston which arrived yesterday. Any tips on the replacement process? This is an XTR 4 piston for reference...Thanks guys...

Stick a compressor in the caliper half you're holding to push the piston out.

Don't forget to aim. You'll be amazed at the distance achieved.

 

[manhattanprjkt83]

That's a good call kidwoo!

 

[HAB]

That's the way to go for removal. When you're putting the new ones in, just be really careful to push them in straight and not bugger up the seal. It's not too hard though.

 

[jonKranked]

@manhattanprjkt83 where'd you source a replacement piston?

@kidwoo didn't you try this in the past with unsatisfactory results? i seem to recall you tried a set of chinesium pistons and they were toleranced poorly.

 

[manhattanprjkt83]

ok this is what I was hoping to hear, that it is a pretty straight forward process...i appreciate the input

 

[manhattanprjkt83]

@manhattanprjkt83 where'd you source a replacement piston?

@kidwoo didn't you try this in the past with unsatisfactory results? i seem to recall you tried a set of chinesium pistons and they were toleranced poorly.

Some weird vendor on amazon, I hope it works...

 

[manhattanprjkt83]

https://www.amazon.com/gp/product/B0855TDKD7/ref=ppx_yo_dt_b_asin_title_o02_s00?ie=UTF8&psc=1

 

[jonKranked]

Some weird vendor on amazon, I hope it works...

interesting. i've got 2 sets of xt m785s with the time bomb ceramic pistons. they haven't died yet (we don't have many long or steep descents around here) but they are making me nervous due to age.

will be following to hear your experience on them. which model xtr do you have?

 

[manhattanprjkt83]

I have the BL-M9120, which are the current 4 piston. Yeah the material these pistons are made from seems more durable almost a polymer type material. I wonder what it will do under heat though...Figure'd I'd try this prior to buying a new caliper. If I wasn't a ham fisted moron we wouldn't be having this discussion.

 

[jonKranked]

i bet you two ugga dugga'd when you only needed one.

i read somewhere when they launched the new stuff that the pistons are still ceramic, but couldn't find any more detail than that.

 

[kidwoo]

I bought some aluminum ones off ebay straight from china. I need to try them again with new pads. Hopefully those work for you. But yeah, they're easy to switch.

 

[Da Peach]

I have the BL-M9120, which are the current 4 piston. Yeah the material these pistons are made from seems more durable almost a polymer type material. I wonder what it will do under heat though...Figure'd I'd try this prior to buying a new caliper. If I wasn't a ham fisted moron we wouldn't be having this discussion.

I would try for a warranty. XTR, bro.

Mine cracked when I was trying to push them back in during a pad replacement. I got a new brake gratis.

 

[manhattanprjkt83]

You have a point, I might shift my approach here. I found an XT single piston caliper in my tool box which could get me through the next couple weeks here.

 

[jonKranked]

I would try for a warranty. XTR, bro.

Mine cracked when I was trying to push them back in during a pad replacement. I got a new brake gratis.

its worth a shot, depending on how exactly @manhattanprjkt83 broke them

 

[marshalolson]

Just riding along.

 

[manhattanprjkt83]

Absolutely just riding along...I'll give it a shot, see what happens.

 

[Da Peach]

its worth a shot, depending on how exactly @manhattanprjkt83 broke them

If the new XTR are anything like the older ones, they require regular bleeding to feel like they're supposed to. To the point where it falls out of the category on "maintenance" and into the "part of general use" category. That's a lot of fucking around with pistons that shouldn't need to happen.

Absolutely just riding along...I'll give it a shot, see what happens.

Exactly. Especially if you have a backup brake to keep you rolling. For the amount of shit floating around on the internet about Shimano brakes (to which I have contributed much) Shimano ought to give a loyal customer the benefit of the doubt.

 

[rideit]

Just to play devil’s advocate, I have been running these new brakes hard for two years with nary a problem.

 

[manhattanprjkt83]

Let's just hope this XT 2 Piston holds tough for a full weekend of riding at snowshoe this weekend...

 

[jstuhlman]

Let's just hope this XT 2 Piston holds tough for a full weekend of riding at snowshoe this weekend...

STATUS REPORT (brakes and park conditions, plz). (my xt single pistons always held up pretty well there; just an occasional bit of fade if I was too heavy-handed towards the end of the day(.

 

[manhattanprjkt83]

XT Brake held up fine, Shimano warrantied my XTR piston, new caliper on the way.

Snowshoe was sublime this weekend, everything was riding great, there is some newish stuff hidden in there from some of the enduro series which rips!