Originally Posted by flags6262
Your right leg should be straight when the pedal is at the bottom.
For a beginning seat height, your leg should be straight with your heal on the pedal at the farthest point. The farthest point is generaly when the crank arm is inline with the seat tube. This method will allow knee bend when pedaling with the balls of your feet on the pedals. Personnal adjustments can then be made to each riders preference.
Mountain bikers usually have their seat adjusted lower, but , this is subject to personnal preference and comfort per inividual.