Here's the bottom bracket on my 1997 Specialized M2 Pro, which I bought used.



I know you can't see it very well, but is this a cartridge-type bottom bracket?

If not, I plan to replace it with a cartridge type at some point in the future.

Here's my thinking: because I am going to eventually replace it with a cartridge, is there any rush on replacing it? In other words, I normally do overhauls to prevent damage. But in this case, even if there were damage from worn bearings, it wouldn't matter, so I see no reason to replace it until it is not spinning smoothly.

Does that make sense?

Thanks,

Al

If it were loose ball there would be a notched lock ring,
and typically, a series of holes in the adjustable cup,
to hold adjustment, with a pin spanner, while you tighten said lock ring.

Likely Already Is a cartridge BB ..

Yes.

No.

Well, usually not. But odd things can happen between real stubborn riders and BBs that are seizing.

Add developing play to that, and neither do I.

Although riders with a streak of magpie in them (drawn to blingy things) have been known to detect infinitesimally small amounts of notchiness in even nearly unused stuff, and used that for a reason to replace with supposedly better stuff.

Great. If it's a cartridge, then I should get years of maintenance free service out of it, right?

Thanks!

Looks like cartridge to me.

Yes you should. Decent cartridges last 10's of thousands of miles in my expereince. I have a 6500-series Octalink bb with 33,000 miles and it's still smooth and free of play. I've also had older Shimano UN7X square taper bb last over 25,000 miles and be replaced with newer ones (upgrade-itis) while still in excellent condition. Use yours until it tells you it wants to be replaced.