Help! I've popped out a Saint piston...

[RichardGB]

Evening all!

I was bleeding my brakes earlier and made a booboo.
One of the pistons popped out whilst I was faffing.
It popped back in with a little wiggle and I re-bled it. Seems to be holding pressure fine and no leakage. I've left it under pressure (strap around the lever) and I'll check in the morning.

My question is: have I f'ked it?
Shouldn't there be some kind of seal around the piston? I didn't see one? Surely it's not that simple to pop them in and out without repercussions?

I'm off to the Mega in a couple of weeks so want to be sure it's fine before I throw myself down a mountain on snow!

 

[cozzy]

As long as it's all clean it should be fine.

 

[RichardGB]

As long as it's all clean it should be fine.

That's why it popped out. I was giving it a thorough cleaning and just putting some fluid around the partially exposed pistons.

Except I got a little over keen and it popped out on the 3rd attempt.

I'll have another bleed of it all tomorrow/Sunday. Thanks for the reassurance.

 

[RustyIron]

My question is: have I f'ked it?
Shouldn't there be some kind of seal around the piston? I didn't see one?

The seal is on the caliper.

 

[RichardGB]

The seal is on the caliper.

Ah, I wondered if that may be the case.
Does it ever need replacing?

 

[RustyIron]

Ah, I wondered if that may be the case.
Does it ever need replacing?

Over time, the seals harden and become less resilient. The result is that the pistons will not retract properly. Adjustment becomes difficult and performance becomes erratic. You can bleed them, clean them, lube them, and say a prayer over them, but the resilience of the rubber can never be restored. One would think that the solution would be installing new seals. That would be easy. Finding new seals is altogether different. When this day comes, it's easiest to just go out and buy new brakes.

 

[RichardGB]

Over time, the seals harden and become less resilient. The result is that the pistons will not retract properly. Adjustment becomes difficult and performance becomes erratic. You can bleed them, clean them, lube them, and say a prayer over them, but the resilience of the rubber can never be restored. One would think that the solution would be installing new seals. That would be easy. Finding new seals is altogether different. When this day comes, it's easiest to just go out and buy new brakes.

What is it with Shimano and making stuff nigh on impossible to repair?
I almost had to junk a Di2 derailleur for want of a little screw and spring. Shimano wouldn't supply one meaning a £300 unit would be junk without a bit of bodging.

 

[RustyMTB]

One that gets on my wick, their 12 speed cassettes have separate top three or four sprockets I.e. the ones that wear fastest. Great idea except to replace them costs about the same as a whole new cassette, so why bother?

 

[Dax]

This is my big issue with shimano, it seems incredibly wasteful not to supply seals for brakes. I really like how Hope supply spares going back 20 years

 

[Spiff]

I managed to pop out the piston of a Magura MT7, I popped it back in with a little wiggle and I re-bled it.

Two years later, the brake is still performing fine and without leakage. So do not worry.

 

[RichardGB]

This is my big issue with shimano, it seems incredibly wasteful not to supply seals for brakes. I really like how Hope supply spares going back 20 years

I keep convincing myself in and out of buying a set of V4s -
Well, it's mostly my bank balance that convinces me out of buying them - mostly because I know I can source parts.

 

[Dax]

I keep convincing myself in and out of buying a set of V4s -
Well, it's mostly my bank balance that convinces me out of buying them - mostly because I know I can source parts.

Same. Despite swearing off Shimano due to their lack of parts availability, I can’t stomach the £400 for hopes, so stuck a pair of XTs on it.

 

[KnollyBro]

If you have not upgraded to Maven by now, you have completely missed the concept of disposable income.

 

[RichardGB]

If you have not upgraded to Maven by now, you have completely missed the concept of disposable income.

What's disposable income? I thought it was a myth?