[DaveG]

Is there any reason why I can't use the new '06 Centaur bottom bracket with older Veloce/Centaur cranks that used the old-style Mirage/Veloce/Centaur BB with the ridged external cups?

 

[Metaluna]

I'm using a Centaur '06 / Veloce '05 combo right now, and it seems to work fine. The chainline and spindle taper and symmetry are the same as far as I know. I did find that if I torqued the non-drive side cup to Campy's torque spec, the spindle had excessive rotating resistance, so I had to back it off significantly and use Loctite. This doesn't have anything to do with the crankset though.

 

[Spunout]

They are all the same 111mm BB, new style (sealed) or old style (free bearings). Go for it!