BB30 crankset/BB used on a C&V frame?
 

BBs on C&V frame are sized and threaded for bottom bracket bearing sets that thread into the inside of the BB shell. Many modern cranksets follow a standard known as "BB30." I want to consider putting a BB30 34-50 or 30-46 compact crankset on a C&V frame.

Is it possible to do this directly, without revisions to the BB shell?

Bb30
 

No.
There IS a 30 mm BB "standard" which can work in an English BB. I believe that is the BB386, but my memory is often proven... defective. (deficient?) I digress...
Anyway, off the top of my head, the SRAM GPX "standard" is an axle which is 24 mm diameter on one side, 22 mm diameter on the other, while the shimano version is 24mm diameter on both sides, and all the press fit "standards" use 30mm axles. The variances are mostly, AFAICT, regarding overall BB width (Including external bearings.)
HTH.

Bottom Bracket Standards - Slowtwitch.com

a reasonably good explainer.
Essentially you cannot get there from C&V there

The closest you are going to get is being able to put a BB386EVO 30mm crank into classic threaded BB using this external bearing.

https://www.performancebike.com/bike...551_1139439_-1


Many PF30/BB30 bikes use longer 30x86mm spindle cranks, like Rotor, with spacers at each end. True BB30 cranks only have 30x68mm spindles, so they will only work in those narrower BB30 bikes.

English threaded BBs are about 68x34mm on the inside, so there isn't enough room for bearings when you have have a 68x30 spindle.


So the answer is "sort of", if you consider something like a Rotor to be a "BB30 crank".

I see. I have an Italian frame, to boot.

There are 30 mm BSA external bearing setups available now - but I'm pretty sure not in Italian.
However, a standard BB30 crank won't work, the spindle is too short. You need a 30 mm crank designed for it with a longer spindle.

Threading is pointing you to Campagnolo.
3ttt also had a crankset out, wild Italian styling, not sure if compact.

There are many, many cranks available for an Italian BB. None of them will be strict "BB30" cranks, though.

Campagnolo outboard cups are available in english or italian threading, and with an ultra-torque crank will work in any 68mm wide BB shell. Possibly power-torque as well, but I can't say with certainty. What have I missed?