Upgrading MTB hydraulic brakes

MrFunex · 29 Jan 2019 at 20:21

Hi all,

A few months ago I bought a Cube LTD Pro. I love it, it’s almost all the bike I need and I’ve covered around 600 miles on it so far. The brakes, however, aren’t great... both front and rear are Shimano BR-M315 hydraulic discs, but don’t seem overly powerful? They don’t inspire much confidence stopping quickly whilst going downhill and I’m sure a decent set of V-brakes could match them. I know these brakes are fairly basic, but how could I increase performance?

I’m thinking either the cheap option of trying a different set of pads, or the pricier option of buying a set of Shimano XT-M8000s, as well as their Ice-Tech rotors. They’re on offer at the moment!

Am I barking up the right tree?

Begbie · 29 Jan 2019 at 20:31

Or SLX will be fine, deore too most likely.

You could try new pads from the likes of uberbike, but I doubt it'd make much of a difference. Assuming your pads are ok? Stock shimano pads become knackered quickly. I went through a set in two months. Mostly long, rough, hot, dry descents though.

I run m8000s and ice-tech rotors, they work very well.

MrFunex · 29 Jan 2019 at 21:00

Thanks, do you think new rotors are needed? I’m guessing not, as the old ones are hardly bedded in, and there’s not going to be a size change..?

Begbie · 29 Jan 2019 at 21:20

MrFunex said:
Thanks, do you think new rotors are needed? I’m guessing not, as the old ones are hardly bedded in, and there’s not going to be a size change..?

Nah, unless you're doing crazy descents then save some money. They are good, and were an upgrade for me, but margianly.

TallPaul_S · 29 Jan 2019 at 21:40

I've got deore 2 pots on my bike with 180mm discs and on anything but the fastest downhills they're plenty powerful.

XE11 · 30 Jan 2019 at 12:56

before dropping big bucks on new brakes, try buying adaptors and bigger rotors. however, do check if your frame can take bigger rotors tho.

MassiveJim · 30 Jan 2019 at 14:37

I'd defo try pads first.

I fitted some (very cheap) Magura brakes wit 180mm rotors to my old Giant HT and they have decent performance once I changed the pads.

They came with the hard pads in rear, medium pads in front.
I changed to soft pads in front and medium pads in rear, once they bedded in they were decent.

That said I haven't done any challenging descents on them since I got my full sus bike, so can't comment on performance under duress.

MrFunex · 10 Feb 2019 at 08:55

Just to complete the thread, I took the ‘half-nuclear’ option and replaced the calipers with XT M8000 ones. I kept the original discs (180F/160R). In the Wiggle sale, the cost was around £150 for both front and rear.

Due to the weather, I’ve only had a very short ride out, together with many laps on our driveway as I was getting everything centred/set up, but WHAT a difference! I’d imagine the bike can now stop in almost half the original distance; fairly average performance is now properly fierce. Rather shocking the few times I’ve squeezed hard on both levers at the same time!

TallPaul_S · 12 Feb 2019 at 22:07

Grabby, you mean?

I'm not a huge fan of shimano brakes above deore, in fact when on a demo bike, in horrible muddy, slippy conditions, with XT's - they were so grabby I was afraid of pulling the front and locking up they were that grabby. For a lot of people though, that instant grab feeling equals 'power'. Give me a bit of initial bite, then buckets of smooth, modulatable (is that a word?!) power that just keeps on coming, any day of the week.

Having locked up front motorbike tyres due to grabby brakes, that's not my thing.

I really need to buy a set of Hope E4's at some point.