Anyone know anything about disc brakes?

Thanks. It's seemingly impossible to find what I need in the country I live in, so I chose the obvious, sensible alternative and ordered a whole bunch of AXS parts instead as I happened to have some brand new Apex shifters (with cables) lying around.

At least I won't have to internally route a shift outer through my stupid carbon bars now. Clearly worth it...

What PhilDAS said. I was having a very similar issue with stock here in the UK, so bought some of those TRP hose couplers. They worked a charm but don't look very sexy (if that bothers you).

Go back to around page 350 if you're interested in the discussion we had on it here.

Thanks. Good to know about the coupler, will definitely help me in future. Unfortunately, on this occasion, the previous owner cut the hose super close to the shifter.

Would anyone want this for cheapest I can find online but is out of stock, £20?

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Very noddy question but not sure if there's anywhere better to ask it - what's the best replacement for Avid BB5 pads? Need to change mine out on the tandem which is squealing like a banshee but never swapped them out before.

I see these at decathlon, these nukeproof ones, these aztec ones, or given I don't want my partner getting in an accident would shelling out top dolla for the original avid ones be worth it?

IME, there is very little difference between expensive pads and cheap pads. Any of those brands are well into the "absolutely fine" category.

Thanks very much for the advice (:

Edit: Just went to swap out the pads and it seems to me like the BB5 has two separate adjustments needed for each side - one screw that moves the inner pad in and out, and the cable actuation is only connected to the outer pad which pushes the rotor into the inner pad. Seems like a strange brake design to me; have I somehow misunderstood?

Disc brake noob, first time shortening a hose question. I can't remember if the lock nut was originally threaded all the way into the lever body (SRAM S300) but now that I've cut the hose and changed the barb and olive, the lock nut is only going in about 2/3 in by hand. I can tighten it with a spanner but without a torque setting I'm worried I'll crush something. I've loosened things off and try to wiggle the hose in further but feel like it's at its limit. Seems to work fine and no obvious leaking but I'll definitely need to learn how to top up the fluid as I lost more than anticipated.

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but now that I've cut the hose and changed the barb and olive, the lock nut is only going in about 2/3 in by hand.

There is normally a rubber sleeve that slides back over, as it doesn't go all the way back in. If it's not off camera and not fitted... maybe next time :)

If you can find a crows foot tool that works with a torque wrench, it's very reassuring, they do go in quite hard (8nm). Guess the point is you are trying to crush something a little.

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crows foot tool

Very cool, will look out for one. Yeah i put the rubber boot on before and it slid back over fine. Took it for a local spin and the bite point is quite low so will def need a top up, time to dig out my old epic bleed kit and see if any of it is useable.

If you want to borrow the crows foot or a bleed kit, slide into the DMs

anyone actually found these for sale anywhere online?

Getting the nice bike out after winter, one very spongy (more accurately no bite at all) lever. Did a bleed and when I put all back together and squeeze the lever it seems that a load of fluid came out of somewhere in the caliper (shimano road brakes - 785 probably). Something's fucked innit?
a) What's likely fucked?
b) Can a mostly hamfisted me repair it or new caliper time?

Merlin warrantied my Deore 4 pot caliper that cracked as I was bleeding it up, they actually did this a while ago and I’ve only finally got round to fitting and bleeding the new one today and fitting the brakes to my Honzo in place of the Sram Guides.

I was surprised to see that I’d snapped the rear is-post adapter. Presumably a result of using these tall convex spacers which I presume I’ve used as they are what was supplied with the brakes (although I had a one piece +20mm post-post apart on the front)

The Shimano brake is now fitted with the correct size is-post adapter (which is heavier across the bottom than this smaller one) but maybe a smaller is-post plus a one piece post-post is actually better as it braces it better?

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Shimano can be quite picky about how you have the calliper mounted in case you ever need to claim warranty. Their standard mounting position and SRAMs is ever so slightly different. I would suggest going with whatever Shimano supply / recommend for their calliper.

Interesting, I’ve never noticed recommendations of doing it one way or the other. There’s probably a Shimano tech doc out there…

There isn't any definition for how stiff the connection between two mounting points needs to be, but Shimano callipers do have a habit of snapping at the mounting tabs and I have known them to point the finger at the frame or adapter.

Just setting up my possibly-leaky 8070 shifter with a short hose to see if it's still usable. Anyway, the screw you use to crush the olive... I have two types in my spares box; a black one (looks like the one in my other ultegra calipers) and a silver one, same thread, just a little longer. Should I use black at both ends?

It's possible the silver ones came with my hope rx4+ calipers but I don't remember

I think Shimano are always black. The Hope ones I have are silver so your theory checks out.

R8070 end should look like this. AIUI it's a different thread (M9) and you'll damage it if you use the M8 bolt used on everything else.

https://www.sjscycles.co.uk/brakes/shimano-smbh90-flange-connecting-bolt-unit-m9-for-str9120r9170-y8rd98010/

That's the shifter end, right?

Yes.

Shimano have longer silver ones too, they all work the same. Generally on flat bar the black go in the lever and silver in the caliper, although that looks worse in my opinion.

My RX4s have silver bolts used to seal the brakes/crush the olive too.

I’m having an issue with my front disc calliper squeaking and just wanted to check like issue. Is it the piston that’s dirty? I have cleaned it very recently

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