Here I am again with more questions. Just want to make sure I get the right bits for my build.

The new frame I’ve bought needs an 86.5mm press fit BB, an I right in thinking that BB71 and BB91 are exactly the same and just different in terms of quality just like deore to XT?

I’ll be using an SLX triple chainset if that makes any difference.

MTB frames usually run the wider BB92. What frame is it?

The Shimano BBs are much of a muchness, as you say. FSA and Raceface also do some pressfits, and a bit cheaper, but they’ll be no better I suspect. The only higher-end one I’ve seen is the Enduro.

It’s a giant trance x With an 86.5 bb so needs a 2.5 spacer.

I’m really confused Giant states 86.5 shell but all the press fit BB’s say this is a road bb.

The mtb ones say 89.5, so do I use the sm-bb71 and the 2.5 spacer?

so i’ve a related question..

if I bought a bb30 bike, would the cranks fit onto a regular frame, with just a new (external) bb needed?