Wheel sizes One of the most striking characteristics of most recumbents is the use of small wheels.
Small wheels are used primarily to reduce the overall length of long wheelbase designs, and to improve heel clearances on short wheelbase designs. But it turns out there are other advantages to small wheel designs. Road racers using 700C rims are quick to point out that smaller rims have higher rolling resistance. At around 20 mph, aero drag becomes a bigger factor than rolling resistance. So small wheels contribute to higher top speeds.