When evaluating belt drive bikes, the most critical component is the drive system itself, typically dominated by Gates Carbon Drive. Ensure the belt is made of high-tensile carbon fiber to prevent stretching. The frame must have a 'split' or 'break' in the rear triangle (seat stay or dropout) to allow belt installation, as belts cannot be broken and re-linked like chains. Additionally, verify the sprocket material; stainless steel or hardened aluminum is preferred for longevity. For the transmission, these bikes usually require an Internal Gear Hub (IGH) like Shimano Alfine, Rohloff, or a Continuously Variable Transmission (CVT) like Enviolo, as traditional derailleurs are incompatible with belt systems.