Keeping your bicycle adjusted to your body size requires seat and handlebar adjustments. An improperly adjusted seat may lead to permanent damage to genitalia at its worst, and a simple case of numbness at least. In addition to the seat adjustment, the handlebars need to be kept at the proper angle for your riding style. Carpal tunnel and wrist injuries result from an improperly adjusted set of handlebars.

Seats

1. Open the seat stem quick release lever or loosen the stem lock nut. The quick release is a metal lever that turns to tighten the seat stem to the carbon bike frame. Turn counterclockwise to loosen to move the seat up or down. If the bicycle has no quick release, turn the lock nut to loosen the seat stem.
 
2. Stand over the bicycle and place your rear onto the end of the bicycle saddle. Have an assistant hold the front bike wheeland handlebars so the bicycle will not tip over. Push the seat stem up or down until you comfortably fit your bum slightly up at the standing position to the edge of the seat. Tighten the stem to the frame.

3. Sit on the seat, with the assistant continuing to hold the bicycle from falling. Pedal backward and stop with one leg fully down. Check for a slight bend in the knee. If there is no bend, the seat is too high. Lower slightly and pedal again until there is a slight bend to the knee when the pedal is all the way down.

4. Loosen the seat rails under the saddle and push the nose of the seat up or down depending on your position preferences. Tighten the rail nuts.

Handlebars

5. Sit on the bicycle and have the assistant hold the front wheel so the bicycle will not tip with you on it. Reach out and grip the handlebars. Wrap your hand to the shifter and brake levers.


6. Check for locked elbows. If the elbows are locked when sitting on the bicycle and gripping the handlebars, the stem needs to be replaced with a shorter handlebar stem. Take the bicycle to a bike shop to get fitted with the proper length stem.

7. Loosen the two hex screws where the stem connects the handlebars to the bicycle. Do this if the length is proper. Turn the handlebars so the shifters and brake levers turn up or down. Tighten the hex screws when the angle of the shifters and brakes is set to your desired setting.