Old Kona BB help please

[bertberr]

Well, after almost 20 years service, I think the old BB in my 1991 Cinder Cone has finally called it a day. Surprised it lasted this long really, though it did get regular greasings via the grease port. When spinning cranks with chain off and holding seat tube there's a definate roughness / grumbling.

Anyway, having removed the N/D/S crank, my question is do I need to buy one of those C-Spanner things to remove the lockring on the adjustable cup? Or can I just use a piece of metal tube in the notches as a kind of drift?

Also, until I strip it apart I won't know how bad things are in there, but assuming there's no damage to the axle race, would it be best to just buy new bearings (think they're in a cage) and repack? Or would it be a good opportunity to replace with a UN54 or similar sealed unit?

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[jamabikes]

if you want to re-use it, get a c ring spanner. if you dont, drift off with a flat blade screw driver. its standard thread on that side so loosen anti clock wise.

 

[weeman_mtb]

You could tap the ring round with a bit of brass or copper and a hammer, should cause minimal damage if any.

 

[jamabikes]

You could tap the ring round with a bit of brass or copper and a hammer, should cause minimal damage if any.

although after 20 years of being there may be a bit reluctant to move

 

[weeman_mtb]

although after 20 years of being there may be a bit reluctant to move

Very true, the ring will go easily enough I reckon, but the rest of it might be a bit more challenging. :?

 

[hamster]

I've got the tools - if you'll pay postage I'll lend them.

 

[bertberr]

Right, so if I don't mind potentially damaging it, go with the drift option. I suppose the problem with that is I won't know if I'll mind until after I've opened it up and seen what's inside

I've seen a c spanner advertised for under a tenner, says its double ended - 69-76mm and 89-96mm, or there's a smaller one 38-45 and 45-52. I take it they refer to the diameter of the lockring?

Anybody here swapped an old C&C for a UN54 or 72, 26 etc? Are they much lighter? Or is better to stay with the C&C if at all possible?

 

[bertberr]

hampster - thanks I'll bear that in mind!

 

[hamster]

Cup and cone is probably a fraction lighter, and for high load applications (like the rear BB of a tandem) they wear better. Cup and Cone tend to get problems from damp inside the frame rusting out the bearings..

The UN54 lasts well and for the sake of less hassle I'd fit one.

 

[Tad]

If you're replacing the bearings rather than going down the sealed unit then don't buy caged bearings, buy loose balls and put them in with shed loads of grease to hols them in the cups, you'll get more balls in loose than caged.

Though I were you I'd fit a sealed BB, far less faff.