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I'm having a difficult time adjusting my Shimano XT MT75 29er wheelset rear hub.

The hub has a cone and nut only on the rotor side. When I hand tighten the cone as hard as possible the wheel doesn't spin and when I leave the cone a little loose then tighten the nut, the wheel wobbles a little when mounted on the bike.

Is there a trick to adjusting the cone and nut on that particular hub?
 

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Dictatorsaurus said:
I'm having a difficult time adjusting my Shimano XT MT75 29er wheelset rear hub.

The hub has a cone and nut only on the rotor side. When I hand tighten the cone as hard as possible the wheel doesn't spin and when I leave the cone a little loose then tighten the nut, the wheel wobbles a little when mounted on the bike.

Is there a trick to adjusting the cone and nut on that particular hub?
There is a cone on both sides. I trashed the DS one because I could not get the adjustment to hold.

Clamp a 5mm Allen in a vice and put the DS of the hub on it. Then adjust the bearings.
 

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transmitter~receiver
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Dictatorsaurus said:
How tight is the cone supposed to be?
It should have a very slight amount of play when not mounted on the bike, so that when you clamp your q/r down the play is gone but the wheel still spins freely. If you adjust all of the play out without the wheel on the bike, when you clamp the q/r it will load the bearings and cause drag (and stress).
the adjustment difference could be 1/8-1/16 turn between too tight and perfect.
 

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Linoleum Knife
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Dictatorsaurus said:
How tight is the cone supposed to be?
How I do it...

Counter-tighten one side (usually the freehub side) to lock the cone against the nut. Install the axle and the bearings.

Then - on the other side, lightly tighten the cone down until you feel the bearings just barely start to bind up. Thread the lock-nut on by hand until it is snug (but only finger-tight) against the cone.

Then hold the lock nut in place with a wrench, and loosen the cone until it locks in back against the nut.

There should be NO binding, and NO play in the axle. You've got about 1mm to deal with, and it will most likely take 4-5 tries to get it right.

It's a skill. I can get it right on the first try about 80% of the time...
 

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It is a bit of trial and error (and a 3rd hand can be very helpful). Most of the newer deore and above hubs that I've adjusted in recent years seem stiffer than my old hubs, so I set them with little to no play before mounting them with the QR. The ultimate test is after mounted on the bike, spin them with very little force and see how freely they spin (they should go on and on and on . . . and very slowly come to a stop, usually even going back a bit due to imbalance of the wheel/tube/tire). Then check for play. There should be no play once on the bike.

Edit: I should add that sometimes if you packed them heavy with grease, they may initially not spin as freely. Recheck after your first ride.
 

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forkboy said:
??

SLX Uses cup and cone as well. If you ever service your hubs, you too will have to learn the fine art of bearing adjustment.
I've been adjusting and using Shimano hubs longer than you have been riding, including 8 years professionally. I'm am VERY well versed in adjusting them properly and my own hubs seem to last longer than most due to my diligence of servicing.

The new XT and XTR hubs use a different axle and cone configuration than the older hubs and other Shimano hubs including the SLX. Maybe you should do a little research first before making such a remark:rolleyes:
 

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Linoleum Knife
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shiggy said:
The latest XT uses a different axle/cone/bearing design. Much fussier to adjust.
Same design as the M97X's, right?

I've rebuilt XTR's, and 7800 DA hubs a number of times with zero issues. I actually think the new design is quite a bit easier. More little pieces to keep track of, but easier to get everything back together correctly...
 

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Linoleum Knife
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meltingfeather said:
*hint* He probably got the one piece of information about you that he stated (how long you've been riding) from your profile, in which case he does know something about you.
:thumbsup:
You're assuming that stuff on the internets is true and accurate.

The only reason I came back to this thread was to delete my post.
 

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meltingfeather said:
You don't know what he was paid or what his position was, but you have no problem assuming for a jab, I guess. :rolleyes:
Incidentally, getting paid to do something makes you a professional.

condescending much?

Who said he couldn't figure it out? More assuming on your part?

Nor you about him. So it's OK for you to assume a bunch of crap for the sole purpose of showing off your "big internets," but you feel compelled to point out that he doesn't know anything about you? :skep:
*hint* He probably got the one piece of information about you that he stated (how long you've been riding) from your profile, in which case he does know something about you.
:thumbsup:
Feel better....
 

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transmitter~receiver
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forkboy said:
You're assuming that stuff on the internets is true and accurate.
You can't expect people to know better if the stuff you write about yourself ain't true. ;)
forkboy said:
The only reason I came back to this thread was to delete my post.
Me too. :thumbsup:
 

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forkboy said:
Same design as the M97X's, right?

I've rebuilt XTR's, and 7800 DA hubs a number of times with zero issues. I actually think the new design is quite a bit easier. More little pieces to keep track of, but easier to get everything back together correctly...
At least similar. It is easy to assemble. IME the adjustment is harder to make properly and does not keep the adjustment well.

Mainly, I am done with the 77X hubs because of the poor parts availability. I need a driveside cone. Is sold only as part of the whole axle assembly at ~$45. Not worth it.
 

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Dictatorsaurus said:
How tight is the cone supposed to be?
From the first post and this one, it sounds like you might not be locking the cone and locknut (in this case the left axle cap) against each other. Without that locking step, you can expect Trouble pronto, so make sure to lock in your setting.
 
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