markjenn

I'm having continuing issues with the Shimano Deore XT (FH-M775) rear hub on my CX bike. I'd like to just replace it outright, but lace it to my existing rim, and, if possible, use my existing spokes. So I'd like a hub with the same flange diameter and it needs to also be a 32-hole, centerlock disc type, with standard 135mm MTB rear spacing. It appears the most readily-available replacement is the Shimano M785, but I'd like to go with something different than Shimano if I can. Any direct, no hassle, non-Shimano replacement suggestions?

Thanks,

- Mark

HillRider

Not a direct answer to your question but what's the problem with the FH-M775? Any replacement is going to be a lot of work even if the new hub is a direct "drop in' for the current one so maybe there is a satisfactory way to make the current hub meet your needs.

AnkleWork

See:
Formula

joy-tech.com.tw

Also check Sunlite.

Dave Mayer

I have done this before, due to a cracked flange on a hub. It is an ugly, tedious task. Very few shops can be convinced to reuse your existing spokes. And, you have to make sure that the flange diameter on the new hub is the same as your XT.

Since there are no better hubs than Shimano (I have tried dozens of others in road and MTB use), I suggest you fix what you have. Short of your hub shell being cracked, everything on your XT hub can be serviced or replaced:

• If the freehub is gunked up or skipping, then replace it. A 30 minute job and the replacement freehub cost is about $40.
• If the hub cones or bearings are shot, then these can be replaced too. About the same amount of time and cost as above.
• If the hub is completely been through hell and back, and the non-driveside bearing cup is pitted, even this can be replaced. This will take a rare breed of mechanic, but I've done this several times on the higher-end Shimano hubs.

markjenn

Thanks for the suggestions. The problem with my M775 hub is that I've already replaced the freehub body once (due to dangerous jamming) and now the replacement, in less than 14-mos of relatively light use, has developed unacceptable noise and drag. I'm also having issues with bearing adjustment - any setting which results in acceptable play has fairly high drag. Honestly, I've read enough about problems with this hub that I'm convinced it just isn't very good. If there is a drop-in replacement at reasonable cost, I'd like to swap it out.

I can re-lace the wheel myself, so getting this done isn't an issue. And I have no problem whatsoever re-using the spokes.

I was just hoping there was a non-Shimano, reasonably-priced, readily-available equivalent I could re-lace to, bolt up my brake disc, put on my gear cluster and be done with it. But so far, I'm not noting much - everything that is equivalent is expensive and/or is going to require a new set of spokes.

- Mark

zacster

Maybe try an LX hub. My understanding is that the bearings are actually beefier on the LX than the XT. I don't know if there are different levels of freehub bodies that are sold separately, but maybe a different version would serve you better on your existing XT.

The good thing about using Shimano is that all the hubs have the same dimensions so they are easy to swap. I swapped my 1990 7sp hub for a new LX T670 10sp hub without changing the spokes. I also did it half in place, removing two sets of spokes, transferring the hub one spoke at a time in place, then replacing the two sets. I don't think I saved any time doing it this way, but it was easier to keep track of the lacing.

So far I'm happy with my LX hub but it hasn't been very long.

Dave Mayer

Noise and drag? Possibly whoever replaced your old freehub left out the steel washer that sites between the freehub and the hub shell.

And as far as different hubs, most non-Shimano hubs are based on the following:

1. Ratchet spline lies inside the hub body
2. Use of cartridge bearings
3. 4 bearings, 2 inside the hub shell and 2 inside the freehub body.

Each of these is features is inferior to the Shimano design. So I cannot recommend any other hub.

Note that the M775 hub uses somewhat smaller ball bearings and a larger hex head freehub mounting bolt (14mm) than a lot of other Shimano rear hubs. Be careful when re-ordering a new freehub.

markjenn

Replaced it myself and am very familiar with the washer.

- Mark