Originally Posted by KPREN

For mountain biking you will want to reprogram the mid drive as the factory setting are appropriate for Chinese commuting, not mountain biking.
The first setting is about 40% power and will stuff you right in a tree. I have my first 7 levels programed as class 1 and the remaining two class 3. I am seldom in class three and never ran class 3 on mountain bike trails. Just remember, big dogs can run almost 30 mph and you will curse yourself for limiting top speed to 20 mph when trying to beat a storm.