Anyone know anything about disc brakes?

and any noise would be contamination and should burn off.

That's proper honking, pads contaminated/burnt, either need a proper cleaning/sanding or new pads time.

take out the pads, have a look, if it's very shiny, it's burnt out/contaminated.

Sounds quiet to me but perhaps I've lost that specific frequency range from my hearing after years of using SRAM hydro R.

Will take a peek at the pads but they've literally done less than 100km so I'd be really surprised if they are contaminated

Oh interesting. I've had Shimano before which are silent. Is this just the noise SRAM makes?

Reassuring, isn't it?

I'd be really surprised if they are contaminated.

Doesn't take much to get it contaminated/burnt.

Used to have a customer who came in with a horrible squeal after a week, turn out he been holding his brakes on all the time every time he come to a stop burning out the pads.

Using brakes to stop? The fool.

Is this a thing? I didn't realise pads could get cooked like that. Assumed they could withstand mega temps.

It's pretty hard to get bicycle pads hot enough to overheat them with a bit of commuting, you generally need to be going pretty hard down a big hill to get them hot enough to glaze the surface. If you spend a lot of time lightly dragging the brakes though you can kind of polish the surface of the pads which will act the same and reduce friction and make braking noisy and shit.

you generally need to be going pretty hard down a big hill to get them hot enough to glaze the surface...

,..and not let go of the brake levers for a prolonged period of time.

The rotor is means to act as a heatsink and draw the heat away from the friction area so it can pass from the rotor to the air, but if you stay squeezed, the heat can pass into the pad, pad backing plate, caliper, fluid...

FML.

Cleaned the rotor, changed pads, bled the system, everything was fine. Rode home in the rain last week, put the bike away for a few days. Rode into work this morning, no braking power, horrible noise when braking.

BR-RS785 caliper with g03s resin pads (they haven't done 100km, rotor also has less then 500km ) I've done some testing while riding into work and after a while some braking power came back. When braking from 30km/h to 15 km/h, no noise. When braking from 15km/h to a stop --> noise.

Are the pads contaminated again? Do I need to wait a bit longer before they are "worked in"? Sand them down a bit? Bike is stored outside and it was cold this night, could this be of an influence?

last time it was possible they were contaminated but this time I've not touched them.

I've also cleaned the caliper last time as per Park Tool's instructions.

Bit hesitant to take it to a bike shop as they'll probably just replace everything again.

Could have a leak in your caliper. I had that in one of my rs785s. replaced under warranty

There is so much shit on the roads it's not surprising.

Dishwasher liquid and green pad, 5 mins and you'll be able to clean rotor and pads.
Or just ignore sqeek.

hmm. Ordered it online so that's going to be a bitch to replace.

i'll have another clean this evening and see if this fixes anything. Squeak is not a big problem for me, it's the (big) loss of braking power :(

bike shop can test it then send to madison for warranty replacement. takes a month though

03 IIRC is sintered/metal hence squealing is expected from a cold start or at low speed.

Could also be a loose bolt somewhere, tighten everything up again?

https://www.bike-discount.de/en/buy/shimano-g03s-resin-disc-brake-pads-806539

I believe it were these. i'll give it a big check up when i get home.

03 is new improved, quieter, longer lasting resin.

Yeah it’s leaking - Shimano brakes do this because they hate you.

Strange, it is listed as sintered here:

https://images.app.goo.gl/so9H7AyxmpuYhxXr9

Do i replace with hope rx4? it's twice the price as for another rs785 but I'm reading up online and they seem to be regarded as shit.

That's what I did. Have a spare RS785 caliper (without leak) for sale if you want a cheaper solution though.

The image is wrong, note G04Ti in the top but G03Ti in the main table.