I am now in training for cycling. Long time didn't got into bike. I am using a 21 gear mountain bike with highest gear, and around 70 - 80rpm. What's surprise me is my average speed only 12km/h(recorded from strava) and 14km/h(recorded from mapmyride).
I was wondering whether i am using the wrong gear? I thought that the higher with the same rpm will move faster than a lower gear with same rpm.
12km/h is much slower than my expectation. I expect 70rpm would be 20km/h or more.