I just received my Ohm Urban Class 3 speed peddlec bike 8 days ago but have to gradually work my body up to that 28 mph level over a fair distance. We have lots of ups and downs in NWArkansas even on our beautiful regional trail system. As I ride longer and longer distances I will be able to give you more accurate answers, although Ken S has by far the most riding and distance experience on the Ohm bikes and the BionX system. I do find it easy to quickly get up to 23-25 mph on the long straight level sections of our trails with this bike, but our trail system speed limit is 15 so I won't be riding this fast on lengthy rides until I move to more street riding. The only times I have experienced quick battery drain and perhaps some battery heating was when I used the throttle alone going up hills on some more level sections - the BionxD motor really likes you to pedal at all times going uphill. I drained about 8 percent using the throttle plus peddling versus 3 percent peddling at level 4 of assist but no throttle going up the longest steepest hill to my house.