Currently running XT brakes from 2010 with 160mm centrelock rotors both ends. I weight pretty much 90kg with all my kit. I feel like I am not getting enough power from the brakes-i’ll stop pretty quick if needed but even grabbing a handful of lever can’t lock the wheels. I’ve bled them which improved how they felt a bit but didn’t improve the power, and new pads made no difference. What performance should I be expecting? Am I too heavy for this setup?

Should be fine.

Something nasty on the rotors? Do you like spraying fork or any other lube around? Travel with the bike on top/behind a car getting road grime on them?

clean rotors, change pads, bleed.

There should be no issue with a XT brakes, even from 2010, hauling your ass to a stop.

Upping the front to a 180mm will make a difference, both in power and modulation however, rotor/pad contamination or even slight caliper misalignment will dramatically reduce stopping power. Maybe try changing pads and degrease everything to see if there is an issue?
My deores of the same era could happily supply endo’s on a 160, and I weigh the same as you.

Hmm thought as much. I’ve cleaned the discs with alcohol wipes but maybe pads also contaminated at some point. I’ll give those suggestions a try and see how it goes.

However, if you have a spare £100 burning a hole in your pocket, treat yourself to a new set of SLX stoppers 😀

This did cross my mind the other day. Tbh if I pluck up the courage to sell my old frame+forks I may well treat myself to some upgrades.

Saying that, the new Deores are very good as well.

Older XTR calipers and XT levers on my HT, basically the same as an old type XT, 180F / 160R rotors, and I’m ~85kg. So not very different from you OP.

Keep the rotors snd pads clean, and keep an eye on the pad wear, and thoroughly reverse bleed them. 180mm front rotor made a big difference over a 160, but I’m not sure I’d want 200 up front might make it a bit sharp and lacking in modulation, 160 at the back is bob on IMO…

depends on your weight and relative hand strength. I buggered up my hands in a crash so went from 185/160 rotors to 205/185. Easier braking and now no arm pump!

edit – to counteract cookiea apprehension, I’ve never managed to accidentally endo on the flat due to having too much braking power at the front.

You should manage to lock everything up with 1 finger braking if they’re set up right without any contamination.

Sounds like either contamination, caliper misalignment or new pads still bedding in.

I would be tempted to clean the rotors with isopropyl alcohol, score them up a bit with some sandpaper (or maybe even put some new rotors on), put some new pads in and see how it goes.

The only time your weight could be a problem would be on huge very steep descents where things could get a bit hot.

Must admit I didn’t like the old xt brakes, seemed pants but I’m heavy.
Just fitted some new xt’s in place of my xo elixirs and they are **** awesome.