Tandem bicycle stem that is clamped around the captain's seatpost. The stoker handlebars are typically bullhorns or drop bars with "dummy levers" instead of brake levers for gripping. Because of the extra weight and stresses, tandem wheels may use a higher spoke count, sturdier rims, higher pressure tires, a stronger freewheel, dishless spoke configuration, or asymmetric wheels. Tandems wear out rear wheels faster than front wheels; therefore, they may use non-symmetrical wheel setups, such as more spokes or a sturdier rim on the rear wheel. The dish of a wheel measures the amount of asymmetry between the rim and the hub flanges.
Bicycle brake terminology) uses a series of rods and pivots, rather than Bowden cables, to transmit force applied to a hand lever to pull friction pads upwards against the inner surface, which faces the hub, of the wheel rim. They were often called "stirrup brakes" due to their shape. Rod brakes are used with a rim profile known as the Westwood rim, which has a slightly concave area on the braking surface and lacks the flat outer surface required by brakes that apply the pads on opposite sides of the rim. The rear linkage mechanism is complicated by the need to allow