I have picked up a centrelock xt775 hub on mavic xm317 rim and there is play in the hub- how do I tighten that up- doesnt seem to be a tarditional cup n cone set up???

they are cup and cone. If you take the qr skewer out, you’ll see some allen key fittings in the end.

There’s a tech doc somewhere on one of shimanos websites showing an exploded view of it. If you’re familiar with normal Shimano hubs, it’s pretty self explanatory once you’ve seen it.

IIRC one end needs a hex key & the other is normal cone spanners, tightening is as for normal cup & cone

[edit] as cp says! [/edit]