I already have the Vumaquad and am looking at replacing it with the THM M3. No need to buy a new bottom bracket? (Shell is standard BSA 68mm).

They should be the same.

Alot of BSA BBs these days fit the 30mm axle. The only issue seems to be the thickness of the cups & precise bearing location within the cups, each of which can affect the chainline. The width of the manufacturer's bearing might also make a difference, although most seem to use the 7mm wide bearing.

THM makes both mtb & road cups for the M3, and using a mtb cup on a road frame will reset the chainline. Not sure of you have access to both brands to check the thickness. Final analysis is simply an actual measurement of the chainline I suppose.

They are probably NOT the same if the M3 uses the same BB's as the Clavicula.

The Clavicula BB is offset to one side, in that one side being thicker than the other. But as far as I know the Vumaquad isn't. So unless the Vamaquad BB is as slim as the slimmer side of the Clavicula ( assuming same BB used to in the M3), you won't be able to use them.

I know the vumaquad and lightning cranks can share BB's (personal experience), but I've never heard of THM working the same way.

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Speedplay is the devil.