你说的是40 miles还是40km?
面是Wiki说的,如果是top speed的话,两个小时是可以骑40m。不过大部分业余初学者做不到吧。
For cyclists in Copenhagen, the average cycling speed is 15.5 km/h (9.6 mph). On a racing bicycle, a reasonably fit rider can ride at 40 km/h (25 mph) on flat ground for short periods.
