XTR M9000 Race Brakes... Power and Reliability

NobbyClarke020
NobbyClarke020 Posts: 4
edited October 2017 in MTB workshop & tech
Morning All,

Has anybody had any luck with the above XTR brakes in terms of getting them to work reliably with good power ?

I've read a fair bit about these and that they can 'weep' fluid ever so slightly from the piston seals when left stood and also the fact they 'pump up' in use.

I've got a set that came with my bike and can vouch for the fact they do the above. They have nice modulation but the power is seriously lacking and they do indeed pump up quite easily (which would suggest air in the system) ?

I've burped them and bleed them, cleaned the rotors with IPA and tried a few different pads as well as blasting a set with a MAPP torch but it's not a massive improvement. I'd like to drop a set of genuine Shimano metallic pads in but at £60 I'm reluctant in case they are destined for the bin and that money can go toward a new set of stoppers.

Anyhow, I notice quite a few of the GMBN guys run these on their bikes and you would presume they provide reliable and ample breaking for them...

I'm reluctant to haul the bike around a load of bike shops for their expert opinion, only for them all to just give them a bleed and not ultimately solve anything. I also don't really want to bin Shimano's top end stoppers and simply admit they aren't fit for purpose and replace the lot unless absolutely necessary.

All ideas/ fixes very welcome.

Thanks
Paul