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Discussion Starter · #1 ·
My bike recently started making this noise, after some rides in the rain I did in Austin last week. It's sort of like a grinding/croaking type noise once every rotation. You may have to turn up your PC volume to hear it.

The hub was recently repacked about 500 miles ago, and it still feels real tight. Anyone ever heard this or know if a simple lube or repack will fix it? The last time I had this problem the bike shop told me the Deore hub was not fixable, and that's when I ended up buying this XT hub which has been going strong for 2 years now.

 

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Sounds like....

the freehub is having issues. Shimano freehubs aren't serviceable for the most part, but they are easily replaced. So are the freehubs on Deore hubs by the way. The hub will have to be completely disassembled and then the freehub removed and replaced with a new one. Perfect time to do a good cleaning, replace the bearings and repack with grease. This is a fairly easy operation if you have the correct tools and the know how. However it can be a nightmare if you don't know what you are doing.

Anyway, as long and the bearing cups and the cones are in good shape, and there are no other hidden problems, the hub is certainly repairable.

Good Dirt
 

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Squash said:
the freehub is having issues. Shimano freehubs aren't serviceable for the most part, but they are easily replaced. So are the freehubs on Deore hubs by the way. The hub will have to be completely disassembled and then the freehub removed and replaced with a new one. Perfect time to do a good cleaning, replace the bearings and repack with grease. This is a fairly easy operation if you have the correct tools and the know how. However it can be a nightmare if you don't know what you are doing.

Anyway, as long and the bearing cups and the cones are in good shape, and there are no other hidden problems, the hub is certainly repairable.

Good Dirt
I'm going to partially disagree.
If the bearings are screwed up then you might be looking at replacement (or a very fiddly attempt at repair) but most likely it just needs re-lubing which is relatively easy.
You'll need cone wrenches, a chain whip, the appropriate sized Allen keys, some grease for the bearings and some thick oil (Phill Wood Tenacious or similar, I use the bar & chain oil that I use to lube my chain) for the freehub bearings.

-Pull the wheel off.
-Take the cassette off
-Take the axle out (don't lose the ball bearings!)
-Using the correct sized allen key (it's a big one) unscrew the freehub body from the hub.
-Use a pick, needle or something sharp to get the seal off the freehub and expose the freehub bearings. The seal you want to remove is the one on the end of the freehub that faces the hub.
-Dribble some thick oil into the freehub bearings (you don't want to use grease as grease can get thick enough in the cold to cause the freehub pawls to stick and stop it from engaging). You don't need too much oil, maybe a teaspoon at the most.
-Push the seal back into place on the freehub and re-assemble everything (I'm assuming you know how to repack & correctly adjust the cup & cone bearings on a Shimano hub).

The freehub bearing have hardly any load on them as they really only come into play when you are coasting. Given that the problem started after a few wet rides it's probably just a case of them being a bit dry.

Edit: You'll also need a cassette lockring tool.
 

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Discussion Starter · #4 ·
Thanks for the help. It looks like I'm going to be busy one of these days. I have all the tools except the grease. The shop did the repack for me, but I've been taking on more and more repairs to save money, so I guess it's time to learn something new and try this myself.

Hopefully I can also fix my old deore wheelset so I can put my slicks on it. We'll see...

Thanks guys!
 

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I had an old hub that sounded similar to that.

In my case it wasn't the freehub. I opened up the hub and found that a cone had self-destructed on me. A new cone and some new bearings and it's rolling pretty good again, not like new, but for the commuter bike it works.

Wheels Manufacturing makes replacement cones if that turns out to be your problem.
 

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If it grinds while pedaling it's more likely the hub bearings. If it only makes grinding noise while freewheeling, it's most likely the freehub. In your video it makes me think it is the freehub. Like mentioned before, they are replaceable. I believe you can do the work yourself, maybe practice on the Deore hub first before digging into the XT.
 

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I do concur that it's likely the freewheel. BUT...
It would'n't hurt to open it up and replace the bearings. Aside from the tools listed above I would recommend two more for servicing hubs.

An old baking sheet to place under the hub to catch Ball bearings that fall out


and a magnetic pickup to extract the ones that refuse to fall out. The grease will hold some of them in.


For the cost of a yuppie coffee you can buy a bag of 25 grade ball bearings and replace both hubs. This is important because the BB's do wear and when they are out of round they will gouge the cones and cups of the hub. Remove the bearings, and grease. Replace bearings with new ones and repack grease. Time: 5 minutes. Adjusting cone preload until you are happy, 30 minutes. :madman:

I know that some others will try to argue oil vs. grease. Fine. I pack my hubs with trailer bearing grease and frequently keep up by coasting, with people pedaling in front.:thumbsup:

The freewheel is trickier, but not unsurmountable. Since the freewheel needs oil and not grease it's easier to just flush and relube, Flush the freewheel with degreaser and water into a container of some kind. Run a magnet through it. If the magnet is clean then it was just dirt, it you find metal bits then you should consider a replacement cause it's gonna die on you. You'd be amazed at the size of the grit that gets past a "dust" seal. Even a tiny piece of rock the size of this . is going to make a racket in the bearings

techdocs.shimano.com is a great source for exploded views, making reassembly easier
 
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