Pressing the lower button will put you in set mode and toggle you through each setting (hour, minute, second, month, data), the upper button allows you to scroll through the numbers for each setting. You can tell you are in set mode when only one of the numbers (like hour or minute) are displayed. Don't feel bad, the translated English manual is unintelligible in places, and this is one of them. Even when set my clock loses a few minutes each month, but still handy on a ride since I really lose track of time. I ride motorcycles too and it still amazes me how much fun this thing is to ride.
