Does a crankset upgrade need a bottom bracket upgrade?
tl;dr: Should I buy a new one, can I keep my old one (it's nearly 5 years old), or does it depend on if it needs to be changed?
I have a 2016 Specialized Roubaix. I'm interested in upgrading all of my components, which will include the crankset. Should I replace the bottom bracket (BB) as well? What's the conventional wisdom? It seems as though people are all over place on this one. Some guy said he had his for 50 years? While another said that he replaces his every four or five. So do you guys wait until it goes "bad" or is it better to replace it every few years?
The sales rep I spoke to said that it's better to replace it when replacing the crankset for a few reasons:
1) If I use my own (which is a BB30), I'll need an adapter to connect that older bottom bracket with the new crankset (which I believe uses BB60?) and by doing that, over time, more parts can lead to squeaking and rattling issues and what not.
2) I think he said that some of the ball bearings might not sit right or fall out of place or something? Which then would affect the crankset in a negative way somehow? Didn't quite follow what he was saying and there to be honest. Any idea what he was talking about and how often something like that happens? What do you guys think?