For road bicycles, using conventional sized wheels, BB drop (BB spindle centerline below wheel axle centerlines) has been empirically arrived upon at about [240mm minus crank length] for useful cornering clearance.
(For road bicycles; using; conventional sized wheels) (BB drop; has been empirically arrived; upon; for useful cornering clearance)
For road bicycles BB drop
using has been empirically arrived
conventional sized wheels
upon for useful cornering clearance