Trying to work out if I can transplant the crankset from my 2015 Spectral EX8 to a Bird Zero TR.

So I contacted Bird, they tell me the BB shell is threaded 73mm, and suitable for 24mm spindle crankset only.

Canyon tell me that on my Spectral the shell is 73mm (with a supplied PF30 BB). But they also told me the supplied BB is 92mm. I don’t understand how you can fit a 92mm BB in a 73mm shell. And I believe PF30 is 73mm so can’t understand why they are saying the BB is 92mm.

I can see “GXP” on my Canyon BB.

I think it’s important because if my BB shell (and supplied BB) is actually 92mm then I believe that means my crankset spindle is 24mm and therefore is compatible with the Bird. However if my BB shell (and supplied BB) is 73mm then that means my crankset must be 30mm and I don’t think it will be compatible with any of the BBs that will fit in the Bird BB shell.

It’s such a minefield! Any help or advice would be greatly appreciated.

cheers
Paul

My spectral (after I flung the supplied useless raceface BB away) has a Wheels manufacturing BB92 with a set of 24mm Shimano saint cranks.

Take the cranks off the Spectral and have look? The Bird will need a new bottom bracket as it’s a regular threaded one rather than the push fit one on the Spectral.

Hope do a bottom bracket for 30mm axle cranks if they do turn out to be that. If the cranks on the bike are Shimano they’ll be 24mm so it’s easy to find a new bottom bracket to fit.

Thanks folks, sounds good