Can you replace the bearings in a Shimano front hub?

[TGG]

Hello,

In getting my Trek 7.3 ready for the winter, I've stripped my Shimano HB RM32 front hub and found the bearings to be worn out.

Is it possible to just replace the balls or had I got to buy a new hub?

Cheers.

TGG.

 

[HLaB]

Yip, Shimano IME run cup and cone ballbearings, the cup/cones may however be pitted if you've left it too long and may need replaced too. Youtube will have 'know how' vids I opened up my old hubs (my current hubs are sealed).

 

[TGG]

Hi HLaB!

Thanks for the quick reply :-)

After cleaning all the crud and grease off, the cup and cones look OK.

I'm off to my LBS at lunch but I wasn't sure if you could just buy the bearings. Should this be the case?

Cheers.

TGG.

 

[HLaB]

Yip ou can just buy the bearings

 

[TGG]

Just been into town and bought the bearings for a quid :-)

Thanks for your help.

TGG.

 

[andrew_s]

The cups generally are not available as spares, even if you could get the old ones out.
Cones are usually available, but there are many different versions for different hubs. Usually they differ in the sealing arrangement, but they can also differ in the contact angle. It can also be the case that the cost isn't far off a complete hub.

If you swap the balls for new ones, use loose balls that all come from the same packet. If you are replacing caged balls the correct number is one fewer than as many as will fit in. Caged balls are used because they are easier for fast assembly, not because they are better.

 

[Davidc]

If both cups and cones are OK it's an easy job ( see andrew_s & HLaB above). I've just done a rear wheel and it took me about an hour. Use good quality grease for packing (LBS will supply).

Dynamo front hubs are fussier as you have to be very gentle to preserve the wires, but still not difficult.

 

[andrew_s]

Dynamo front hubs are fussier as you have to be very gentle to preserve the wires, but still not difficult.

Shimano dynohubs are officially non-serviceable, which means that spare cones aren't available. You have to bend the wires somewhat to unthread them from the cones and seals, and they become brittle. Servicing dynohubs is therefore not something that is recommended as a regular routine.