Correct saddle adjustment is important to prevent knee injury and increase efficiency.
Proper adjustment of your seat height, angle and position is important in order to avoid injury and improve your cycling efficiency.
Adjust your seat height by loosening the pinch bolt where the seatpost slides into the frame. Twist the seat to raise or lower the post as needed and then tighten the bolt.
Now get on your bike and place the ball of your foot directly on top of the pedal spindle, when the crank is at the bottom of the rotation. Your leg should be just slightly bent. If your leg is too bent you will need to raise the seatpost, and if your leg is too straight you should lower the post. Another way to check this is place the heel of your foot over the pedal spindle. Your leg should be exactly straight in this position.
Seat angle and position are adjusted by loosening the seat clamp under the seat. These often have a lot of parts so be sure to only loosen the clamp enough to move the seat around.
Your seat angle should be horizontal, but you may want to play with the adjustment. Women often like to have the nose pointing just slightly downward, while men often feel more comfortable with the nose pointing slightly up.
You’ll notice that the seat has two rails that the clamp tightens on to. This allows the seat to slide forward and backward, which adjusts your body’s distance in relation to the bottom bracket. For proper positioning, place the ball of your foot on the pedal spindle with the crank arm pointing directly forward. If your seat is in the correct position your knee should be directly above your pedal spindle.
Now tighten your seat bolts and go for a test ride. You may have to play with these adjustments several times until you find the seat position that is most comfortable.