How to Change the Stem on your Mountain Bike in 7 Simple Steps
To change the stem on a mountain bike, first remove the top cap and loosen the stem bolts using a hex key. Then, slide the stem off the steerer tube and slide the new stem onto the steerer tube. Tighten the bolts back up and reposition the handlebars to the desired height. Finally, align the handlebars with the front wheel and tighten the top cap.