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Make/Model?

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Is this the silver skinny one you are talking about?

http://bike.shimano.com/media/techdocs/content/cycle/EV/bikecomponents/HB/EV-HB-7710-R-1729A_v1_m56577569830647971.pdf

But this particular hub does not have sealed bearings. And neither does the silver fat one.

But if it does, go on youtube and search for hub service sealed bearings. You'll find something similar.

You've got the best manufacturer of track hubs, so protect your investment by buying the right tools to service your hubs, a couple of cone spanners from Evans Cycles down the road from you should not cost anymore than £20. Sealed bearings if knackered might be another £16-£30. Do the job yourself. Be confident and do it yourself. You're already in the poo so you cannot make it worse.

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