I have just taken one of these apart, and it is pretty different to my older 765's. Have had a look on the Shimano website but still have a few queries.

On the inside of the freehub, where the 13 balls go, there appears to be a little notch, or key – is this meant to be there ?

The allen key that took off the freehub body on a 765 is too small for this one – what size do i need ?

and finally, when resetting the cones, it seems to me that you hold the drive side with an allen key (as the cone spanner socket is away inside the freehub) and then there is just a singe nut to tighten with a cone spanner on the disc side. Once I put the outer nut on this side, I can still adjust the cone tension by hand – doesn't seem right…..(as compared to the older system where you had the 2 cone spanner nuts which locked against each other)

13 balls? Definitely different, usually 9.

Notches in DS bearing cup always there, it's for assembling the freehub.

Sure you can't get 2 cone spanners on NDS?

I haven't worked on a 775 btw.

cynic-al. Yeah, I was a bit surprised when 13 balls came out, the other side is different too – the balls are in a neat little plastic race. nowt like a 765 though !

the nds only has one cone nut (and that's the way it is shown on teh shimano website)

I think a wee trip to lbs may be happening….

Best to remove the axle altogether and tighten the cone/locknut on the drive side first. I do this by removing both locknut and cone, cleaning the threads and replacing them by supergluing the locknut tightly in place then nipping the cone tightly up against it.

Then you can replace the bearings and slide the axle back in. On the NDS, use a cone spanner to tension the cone and two 5mm allen keys, one in each locknut to tighten the NDS locknut.

It's a faff but it seems to be the most effective way to remove play.

I have to say that I don't rate it as a hub – very high maintenance/quick wear and non-replaceable.

Thanks Stuartie. driveside seems okay, as the cone and locknut are pretty well nipped together, and once the axle is back in the lock nut is inside the free hub body anyway. The 2 allen keys is the bit I was missing – I can see how that will solve it.

also realised that I need a 14mm allen key for the freehub body.

still surprised about the notch in the DS bearing cup, I guess it was there on older ones, just never seen it !

FH-M775 exploded view

Different bearing set up to what you would expect cynic-al.