It really depends on my training goals for the day and the time of the year. Typically, Zone 2 rides hover around 30 km/h (18.6 mph). During the winter, these go down to about 27 km/h in the wind and rain. During the summer though, I typically will do 31 km/h. If I'm riding Zone 3 (Tempo) during the warm months, speeds will go up to just over 35 km/h (21.7 mph). Time Trials, of course, are significantly faster as you ride in an aero position without stoplights. For these, I do about 42 km/h (26 mph).