JohnClimber wrote: ↑Mon Feb 01, 2021 8:15 pm

TraversBikes wrote: ↑Mon Feb 01, 2021 7:59 pm Now back to saying how much of a nice bloke I am....

OK, you're a very, very, very nice man.

https://www.youtube.com/watch?v=KHbzSif78qQ

i for one appreciate your input and your reasons make sense [esp eccentric BB and fitting all cranks]
Perhaps the issue is that the first bike many had with press fit came for a certain maker not known for its QC and therefore there were lots of failures that it has never really recovered from the bad press?

as i said the two i have are working fine - which is great as i dont have the faintest idea how to fix them or remove them.

Going off topic slightly but I also think it’s worth addressing an attitude I see pop up often, about BB shells but also the other standards that are introduced from time to time. I see comments (including in this thread) that the factories are only doing stuff like this because it’s cheaper/easier/quicker. The factories are only making what their customers are asking for. They’re not the ones pushing these new standards. I would imagine having to tool up for these newer standards are more of a headache for them. My dealing with factories in Asia isn’t extensive but I’ve never had a conversation where my design has been influenced (in this context) by what the factory finds easiest to do. JamesO will have had much more experience than I have, it would be interesting to hear his thoughts.

Sorry to go back to BB standards, just a reply to Steven here. My thoughts pretty much as yours Steven. If I was making frames myself / in a place I and others had control of processes, or the material suited, I'd use press fit standards if the reasons justified it. I've been pretty vocal in criticising the use of PF BBs across to many bike types or factories and tbh the original BB30 just didn't seem like a great idea but I'm sure a Cannondale engineer's take on it all is worth a lot more than mine as a product generalist. I still think it was more about Shimano's 24mm axle IP than anything else. BB stiffness is too easy to distract too many riders with.
I never specced a PF BB on a Pinnacle bike because it wasn't needed, we'd be adding another thing to keep tabs on in factories where seat tube reams drifted as it was - and they weren't a bad factory at all. A number of premium brands are made there. Just the reality of mass produced Alu frames ime.
But, yes I am influenced by what a factory finds easiest to do to some extent - if the feature isn't a deal-maker/breaker then it can be good to use a factory's most familiar process or the thing that means the line or process changes as little as possible. More so on working through QC/QA checks than frame specs yes, but all in all you're a 300 or 500 bike order in a place that does 2000 a day. Consistency helps. This is where I think working with a factory's process (build on rather than try to dictate) and the right factory selection helps long term or hinders brands that jump factory for a couple of $ savings every year or 3.

stevenshand wrote: ↑Mon Feb 01, 2021 6:09 pm I'm genuinely interested in this outlook and where it comes from.

I think it's probably just from bad experience with an on-one with some terrible early PF standard, the BBs had plastic cups are were total junk. Maybe newer standards are better, do the bearings press directly in to the frame/metal interface? If so, then I can't see how they'd be any worse than, for example, a hope BB, which is threaded with bearings pressed in to it (which I just replaced the bearings on mine by pressing them in, in situ).

I think I just have PF PTSD.

mountainbaker wrote: ↑Tue Feb 02, 2021 3:04 pm

stevenshand wrote: ↑Mon Feb 01, 2021 6:09 pm I'm genuinely interested in this outlook and where it comes from.

Maybe newer standards are better, do the bearings press directly in to the frame/metal interface?

I guess that was the point of my initial message. The standard doesn't define how it should be implemented. It sets out the parameters for, on one side, frame manufacturers to follow and on the other side, the component manufacturers to follow so that there should be interchangeability. Some implementations are better than others as we've seen. I'm also totally aware that the consumer doesn't care abut all that sub standard and just wants something to work.