imobilinpedalus

On many Shimano BBs, it says "do not disassemble" What happens when you remove it, no longer useable? Just wondering.

HillRider

If you remove it intact it's perfectly fine to reuse. What they mean is that it's not user serviceable if the bearings wear out or develop play.

That said, given the willingness to spend more time and effort than can be justified by the low replacement cost, it is possible to rebuild them as a recent thread on this forum demonstrated.

imobilinpedalus

Ah, another lesson learned Thought maybe the threading was some sort of one time deal because of that warning, lol. So what is a common tool for installing a Shimano threaded BB, are they all the same size? I have two Park Tools BB 29s, but they do not fit.

I think rebuilding BBs is quite a ways into the futurum spectacularus for me. Nevertheless, i will have a look at that thread and see if it is compatible with my english threads. I`m speaking in riddles, i know...

fietsbob

No, of course not things change over decades the UN 26,55 etc type are similar*
loose ball types whole different tool set

* mass produced so cheaply your Time may not be worth the bother..

there was a how to video link posted in the past week , if time is on your hands..


..

pesty

Had to go check my tool box for this one as I haven't had a threaded BB in a while. Assuming this is a road BB; What you want are Shimano TL FC-25 and TL FC-32. The FC-25 is a plastic ring that fits the road BB splines on one side, the other side fits into the FC-32. I'm sure there are tool mfgs out there that make compatible wrenches, but those are the Shimano recommended tools.

noglider 

I once rebuilt a cartridge BB that wasn't meant to be serviced, only because I didn't know that's what it was. But some are easier to do than others.

alcjphil

Shimano makes bottom brackets for different standards. The most basic are their square taper cartridge bottom brackets. In the past they also made serviceable cup and cone bottom brackets, the best of which were of superb quality. Later on, they introduced their Octalink bottom brackets, most of which were cartridge units that required no service until they wore out. The exception to this were the Dura Ace versions that could be serviced and adjusted. Currently, their external bearing Hollowtech II bottom brackets are considered to be non serviceable, but there have been aftermarket ways to rebuild them. First off, you have to determine exactly which Shimano bottom bracket you have. Once you know this you can determine what it would cost to replace vs how much your time is worth to attempt to service it keeping in mind the possibility that you might not succeed in extending its lifespan. An inexpensive square taper bottom bracket that is worn to the point that there is excessive play isn't worth any effort at all

CliffordK

I haven't done it, but the IRD bottom brackets appear to simply use standard sealed bearing cartridges, and should be easily rebuildable.

They also are one of the few brands that supply multiple different cups for different threading.

Do you have a link? I missed it.

Dan Burkhart 

It's amazing the things we did before we knew it couldn't be done.