Anyone know anything about disc brakes?

Cheers. I got them bled about a year ago by a shop, maybe I'll learn to do it myself if it's going to be a semi- regular issue..

I'll learn to do it myself if it's going to be a semi- regular issue..

A: learn to bleed them yourself anyway
B: you shouldn't have to do it very often if the bike is kept upright. Laying bikes down or turning them upside down is the main non-failure cause of air bubbles in the hoses

Could have been the piston getting stuck in the lever with some brute force braking. Did the lever/s go floppy?

I don't think so, I just noticed that I could suddenly pull the lever back to the bar and there was a distinct lack of bite. I thought perhaps some brake fluid had made its way onto the pads, but it seemed to return to normal operation a few mins later.

I'll see if I can replicate it on the way home tonight.

Check the hoses all the way along too, I had one where the hose had failed enough that squeezing hard let fluid push out a bubble from the hose failure but it still held liquid and went back in again and felt more normal when not squeezing hard.

Cheers, I'll take a look

I had this overheating brakes. Do the bleed, you should change fluid at least every year, and you may have air, too.
Road hydros do indeed feel less powerful than 20 quid shimano MTB brakes, but the right pads and a good bleeding and bed-in make a lot of difference.

you should change fluid at least every year

Nah

you may have air

More likely

Road hydros do indeed feel less powerful than 20 quid shimano MTB brakes

Nah, maybe from the hoods but you've got more leverage from the drops if you bare in mind you've got to pull further, and if rotor size is the same.

a good bleeding and bed-in make a lot of difference

Yeah, but fuck bleeding it all the time if it doesn't need it.

Road hydros are badly designed.

The number of busted diaphragm and sticky pistons outnumber MTB stuff by a good 50 to 1.

Stucked pads retainer pins? 100 to 1!

inherently less powerful than low-end MTB

rotor size has a big impact too. a lot of mtb are 160-180mm; whereas road 140 rear is pretty normal

The 2 pot brakes calipers are essentially the same for shimano road and MTB, they work as well, but lever ergonomics make a difference, you can't get as much force from the hoods as easily and you have to pull the lever further from the drops, plus rotor size is a big thing.

Thanks for all the tips. I tried realigning the caliper before riding home last night as one of the pistons seems to be sticky, and increased the lever reach slightly which has improved matters. Definitely a sharper bite, but still a long way from sending me over the bars which I suppose is a good thing.. I'll give it a bleed at some point as well.

I digress.

The 2 pot brakes calipers are essentially the same for shimano road and MTB, they work as well,

No need to digress. They are the same though, the pad axle spacers are shit on the road ones, but easy to swap out. If you fit an slx flat mount to some road levers you'd not notice a difference.

you should change fluid at least every year

Nah

This is how we get people with crusty Avids filled with some black substance.
Last time I got someone that never did a bleed, the nipple was full to the top of dirt. Took me ages to find what was going on, disassemble and unblock it.

Well yeah, it's worth doing sometimes, moreso with DOT brakes and those that get proper use and get quite hot. But your general commuter tektros or whatever definitely don't need an annual bleed, or at all really unless there's something up with them. I changed the fluid on my GRX I've had for at least 2 years the other week and it wasn't really necessary, they've been used a fair amount too.
I also see old juicys that are working ok for a commuter and bleeding would probably cause more problems than it solves, whatever the black gunk they're running on is doing a good enough job to stop someone on the flat from 12mph without boiling, and when they go wrong they'd be better off with some new brakes.

I semi-annually service two mates’ Spez entry-level hard tail commuters. Nearly 15 years old, live outside, never been bled, have gone through several pads and rotors, still working fine.

I’m hoping to be out of town when they finally need a bleed. I tried to replace the headset on one and couldn’t get the steerer out of the head-tube with a 5lbs mallet. Don’t even want to try bleeding the brakes.

I have an mt401 rear brake that I’ve previously cut the hose down on, it’s now too short for the bike I’d like to fit it to.

It has bh59 hose which seems to be out of stock everywhere.

I believe I can use bh90 but the few places I can find with the longer version of this in stock want £35+ for just the hose.

I can buy an mt401 right hand rear brake with a 4100 lever from crc for less than the price of a hose (https://www.chainreactioncycles.com/mobile/shimano-deore-m410-disc-brake-m4100-lever-/rp-prod212502).

The hose should just undo from the 4100 right hand lever and go straight into my 401 left hand lever right?

If I don’t need to shorten the hose would I still need best fitting a new barb and olive?

Any LBSs got a reel of it?, Don't worry about a new barb and olive if you go the other route unless there's a problem from not worrying about it, which is unlikely.

Eurgh, that would involve visiting my lbs! Guess I could go to my ‘not so local but much better’ bike shop!

I know it's weird, but do one of those audio only video chats.

I know it's weird, but do one of those audio only video chats.

At the lbs? How do I do that? Hide behind a screen a'la Blind Date?! Lol!

I ended up finding a whole rear left brake for like £28 last night so have just bought that.

I bought a new Specialized Epic last weekend and haven’t ridden it yet. Noticed today both levers appear to be leaking. This is my first bike with disc brakes and I’m guessing it isn’t normal?

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Hey, sorry but no it’s not. Worth taking back to the shop where you got it, might even be worth calling in advance to see if it’s something they could turn around quickly for you since it’s brand new.

DOT liquid isn’t snake venom, but you don’t want to ingest it or leave it on your skin. It can damage finishes if left long enough too. A cloth with a dab of dish soap is enough to clean minor spills.

has that appeared or was it there from the start though? i wouldnt be surprised if there was just a bit of excess fluid when they brakes were bled and the levers weren't wiped down

i would wipe it off and then see if it re-appears