Anyone know anything about disc brakes?

Front R8020 brake had a lot of travel in the lever so I filled it up from the lever while letting out the slightly grey oil/water at the bottom. Then shut the bleed valve and pumped the lever to get rid of bubbles.

Put back together and there seems to be oil coming from around the white pistons behind the pads. That’s not good right? Is it fixable or is the calliper fucked?

That’s not good right?

Nope. If your rotor and pads went into it, you’ll have to give them a good scrub to decontaminate them. Purpose made stuff is great, Muc off is better than nothing.

Is it fixable or is the calliper fucked?

Did you push the pistons into the calliper at any point? Are they parallel to the centre line of the calliper?

If you lost brake power before and you’ve identified a leak now, it doesn’t look good for that calliper. If you have mineral oil and time to spare, it’s worth a shot at seeing if you can fix it.

Well turns out that the piston was shattered! Not by removing it, I just used water.

Can I get replacements? Or a warranty job?
Looks like Vanilla bikes who I bought the groupset off have closed down, how would I go about doing it?

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New caliper, might be tough to get a warranty job with the shop shutting down, and probably lacking stock in replacements. I'd grab whatever you can find that's compatible for now and then see if you can tempt someone to do a warranty claim on the old one with some beer and the provisio that you've already got a replacement so 100% no rush.

Are shimano calipers front and rear specific or is it just the mounting plate/hardware? I have an kind offer of a 'rear' caliper on here but when sold online they are sold as front or rear.

Pretty sure flatmount are f/r specific.

I'm building up some a bike with some 2ndhand 7020 shifters. Seller didn't include the compression nuts and I had presumed that they would use the standard ones that my old r685 ones used. Turns out that although they seem to fit the thread they don't crush the olive and I need some special flanged compression nuts instead.... grr.....
Also looks like I need a special adapter for the bleed funnel....

Pretty sure flatmount are f/r specific.

I was convinced of this up until last week when I actually looked at 2 "rear" tiagra and realised I had a set if I grabbed the right adaptors.

special flanged compression nuts instead

This is what all the road levers have moved to now. That bleed adapter is bundled with new brakes, your LBS probably throws away loads along with bleed blocks, I'm sure they'll have an odd spare knocking around for someone nice holding a beer.

Most of them are the same, except Hope make a direct mount flat mount front caliper. Presuming you still have the adapter, you can use a rear caliper on the front.

Probably been asked many times before but can I switch a shimano road caliper (tiagra 10 speed hydro) for a shimano whatever caliper, e.g. a cheap mtb one? Eyeing up a used set but the brakes are FM and I need PM.

Yes, they're compatible.

Avoid banjo-fitting MTB brakes if you want to reuse the hoses.

Thanks!

Edit:SOLVED

Anyone know anything about disc brake levers?

SLX-M7000, the reach adjustment on this lever is as far out as it goes and the screw is TIGHT, if you can turn it (lefty loosey) the plastic knob just jumps. The hose needs cutting down/bleeding so I can take it off. No stock of replacements levers anywhere if it is borked.

Fixed
Took the plastic knob off revealing a metal hex I could get some leverage on. Backed it off and it now works as expected.

Doing some maintenance on faulty Shimano RS-785 calipers.
Piston is crushed on the inside.
Is it worth buying new pistons and seals? If so anyone know the parts numbers? I've struggled finding a manual.
Or should I just by a new caliper and save this for spares?

...I sort of know the answer already.

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2 broken pistons in the same page.. Someone email Shimano already!

Shimano don't sell the pistons or seals as spares. If you get a leak or damaged piston within the warranty period you'll get a new one assuming you're original owner.

But otherwise you're shit out of luck and have to buy a whole new caliper.

This is why I stopped using Shimano hydro brakes on my mountain and road bikes. Sram calipers are rebuildable with piston/seal kits.

A good option is buying Hope RX4 calipers that are compatible with Shimano levers. The RX4 calipers are at least rebuildable. The hope calipers are a tad pricey but forking out for new shimano calipers more than once would cost more in the long run.

I don't think they listen to tiny me

Thanks. I am weighing my options. I've been suggested replacing calipers with SLX m7100 ones. They are dirt cheap at 219dkk a piece including brake pads. But some fancy Hope calipers sound sexy

Yeah the hope calipers come up on ebay pretty often, especially post mount shimano.
Prices seem to vary on ebay, about £100 for a pair seems common but you can get lucky and pay less.
I paid £50 for a pair of sram variants on the forum a couple weeks ago.

But having said that the slx calipers are pretty cheap.
For balance I used shimano brakes on mountain bikes for about 10 years without issue but for some reason suffered lots of issues in more recent years when the designs changed.
Also worth mentioning that the rx4 calipers on my winter bike are waaay more powerful than the shimano calipers they replaced!

For the record.

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Yes!
I currently own 3 sets of rx4's. The third set is waiting to go on the hhsrb. I'm waiting to buy purple bore caps but also waiting for the bore cap tools to come up cheap on ebay. Just missed a pair yesterday even though I have an alert set up that didn't bother to alert me.

Did you invest in the proper bore cap tool?

I might be able to get them trade so it's a quite appealing thought going for RX4. On their website it says they are not compatible with IS mounts. But surely I can use a postmount to IS adapter no?

Also, is it a special bleed kit or same as Shimano?

You'll probably need to get the file out, but it can be done.

If buying from hope direct, they come with syringe and other bleed bits and bobs

What? Seriously? Screw that then