Mystery bottom bracket
 

Can anyone help identify this sealed cartridge bottom bracket? It came out of my ‘84 centurion pro tour 15 (likely not original).

English thread, JIS square taper, adjustable cups and lock ring on both sides (presumably to allow fine chainline adjustment), no markings visible except for thread dimensions, thin groove in center of body, rubber seals on both ends.


https://cimg2.ibsrv.net/gimg/bikefor...90c23b01b.jpeg
https://cimg3.ibsrv.net/gimg/bikefor...c3972056e.jpeg
https://cimg5.ibsrv.net/gimg/bikefor...cb0e0fff9.jpeg
https://cimg4.ibsrv.net/gimg/bikefor...b83ef0fcd.jpeg

Per catalog, the original crank was a Sugino, BB was not identified by brand. I'd guess it's a Tange, just because most (all?) Japanese cartridge BBs were made by Tange.

If the crank has been replaced, knowing what crank you've got might help to nail it down.

Does it need replaced, or do you just want to know what you've got?

--Shannon

Thanks for your reply. I looked at the catalog page again, and it does indeed refer to an unnamed cartridge BB. This is likely the original, as almost everything else on the bike is intact, including the Sugino AT triple.

As for condition, it doesn't appear worn, but it's not exactly as stiff as I'd like. The old grease seems to have a liquified element to it as well-- and it's definitely not the original grease. This makes me suspect that due to it being original (>36 yrs old), and that the bike is well used (rebuilt wheelset, etc), previous owners might have maintained it with some kind of liquid lubrication which has mixed-in with the grease.

It seems very well built and I'd like to try and continue with it-- honestly never liked the concept of disposable cartridge BBs, although I understand and appreciate why folks use them. Do you see any issues if I pop off the seals, wash it out with some cleaner (spirits?), and then re-pack with bearing grease? I've read elsewhere that some folks do that with Phil Wood BBs to avoid rebuilding, especially when the bearings are still smooth.

Update: this post confirms it is original: https://www.bikeforums.net/classic-v...l#post17604349
Luckily, mine hasn't turned into shrapnel yet. I was lucky that extraction was pretty straightforward-- another sign that maintenance was likely not neglected over the years.

I've never heard of anyone taking apart a Tange cartridge BB. I always thought they weren't serviceable at all, although I'm sure someone somewhere has tried it. Phil Wood BBs are very different, and are designed to be rebuildable, which the Tanges weren't. Still, the only thing you risk by trying is needing to buy a new BB, which shouldn't be too spendy. (Unless you buy a Phil, of course.) If you do make the attempt, please consider documenting the process with photos and a write-up.

--Shannon

Will do, thanks :-)

As I understand it, grease consists of oil suspended in a soap-like matrix. The oil can and usually will migrate out of the soap over time, as seen, for instance, in the ring of dirty oil visible on old bicycle hubs at the axle.

Interesting info. All the vintage BB/hubs I’ve encountered over the years usually exhibit one of two conditions: thin dark oily residue seeping out, or thick whiteish-brown caked residue in the cups/retainers. The latter has always appeared to be original, and I assumed the thin stuff had been ‘topped off‘ by PO with some unknown lubricant.

Would different types of grease produce different signs of age/breakdown? Or is the liquidy appearance just an intermediate form along the way to caking up?

Asking the question that way suggests an answer... the carrier thins and flows out, leaving the solids behind as the liquid component evaporates. The whitish component of the remaining residue is probably the metallic solids, (molybdenum disulfide, etc,) the brownish the organic stuff.

--Shannon

A bit late to the party, but I thought I might as well chip in. The bottom bracket looks awfully similar to the Kajita Runners bottom bracket. I believe these bottom brackets were manufactured under the Suntour brand as well.
For reference:
https://www.velosaloon.com/products/...m-from-the-90s
https://cdn.shopify.com/s/files/1/10...G?v=1564060582​​​​​​​