Anyone know anything about disc brakes?

Need new olives, might get away without bleeding it but worth having the stuff to hand in case it's needed.

Thanks. I was figuring they'd need a bleed anyway.

Don't "need" new olives. On a rental fleet of about 40 bikes, including DH, we would swap brakes at least 10 times a week (British tourists) and never had a single problem with a used olive causing a leak. Having said that, shimano normally include a set with new brakes, so if you have them, why not! All they'll need as long as you're careful and don't lasso the hoses whilst switching them is a little "burp" after re-installing.

Pretty much this.

We do that at work too on new bicycles.

Don't need new olives if you don't change the length.

Don't need new barbs if you don't change the lengths, crush olives work by squishing a bit to seal stuff, so you should change them for new squish, although things will generally work without doing so.

So is this wearing too low down on the rotor? If that makes sense?

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Nah, you've not got a non worn spot at the outer edge.

That makes sense. Ta!

My Inbred's look like that. Maybe even further in, in fact.

Pads are a little tall for the rotor, but not by much.

That also makes sense. Would the pad vary in height from one manufacturer to the other? Or is it down to the rotor being thin? I only ask as I would assume overlap would hinder braking performance? Maybe not though. I dunno.

Pad height varies by caliper design. Rotors for my Echo TR brakes ("inspired by" Hope Mono Trials, same pads, but with mineral oil) were hard to find as the pads are 20mm tall.

When the pad overhangs the bottom it will wear unevenly and you'll feel pulsing as the overhang encounters the rotor arms.

That rear caliper looks pretty compact. I wonder if it is for sale on its own (and uses mineral oil).... That and a hylex lever could be a good combo.

edit: ...stuff is designed by magura so must be mineral oil.

Apparently doing two separate rear calipers (140/160) and a single 160 front caliper (with no adapters)

yes... probably patent avoidance or weight weenie-ism.

The center lock design is slightly different from shimano's too (but compatible)

edit: also the 140mm campagnolo rear caliper "should" work with all the normal shimano adapters front AND rear.

Ah yeah, that's a good point.

Anyone know where the Shimano post mount RS785s calipers are in stock (or have a pair for sale)? Cannae find them online except for megabuckz

Is the RS785s a different model to the RS785? I can't find anything matching "RS785s"

Evans and Bike24 have the RS785 in stock tho.

https://www.evanscycles.com/shimano-rs785-road-hydraulic-disc-brake-caliper-EV220542

https://www.bike24.com/p293387.html

And ~£50 seems cheap for hydro calipers to me, I bought BB7 Road S for more than that :|

The 'S' is probably the one with the different (straight) cable routing:

"Modification to the BR-R785
The BR-RS785 brake caliper has other cable routing. Instead from the lever to the outside of the caliper, the cable runs now to the inside of the caliper (straight type)."

It is possible the "S" at the end was a typo... sorry.

I saw the £50 ones but had seen a few out of stock at £35 so had assumed that should be achievable! Perhaps I need to be less stingy.

It's totally understandable to want to get things at a good price :D

Recently fitted a new set of Shimano M445s to my Pine Mountain (same brakes as come on it, but I put them on another bike), and the outboard rear pad is rubbing the rotor, even when the caliper is as far as it can go away from the wheel (using the slotty bolt hole bits).
Any tips or thoughts? Wondering if it's just a matter of letting them wear down til it's okay... Didn't have this problem when I got the bike afaik.

You might get a teeny bit more room if that's all you need by spreading the pistons and then squeezing the lever again, if that doesn't work try again but hold the rotor against the outboard pad to keep it as retracted as possible. You might also get a bit of room by doing the QR a little tighter or looser.