Editor’s Note: This article is courtesy of the team at Art’s Cyclery. The original post can be found here.
Properly setting up mountain bike suspension can seem like a magic trick to many people, but by following a few simple guidelines you will be pointed down the right track in no time. Here’s a step-by-step guide.
The first step is determining sag, which is the distance your bike settles into its travel when weighted. Make sure that your fork and shock have travel indicators and if there are none, install a zip-tie yourself, but not too tightly so that it will move when you compress the suspension.
Place the bike next to a wall or have a friend hold the bike while you climb aboard. Wear what you would on a ride, including helmet, riding shoes, hydration pack, and armor. Stand on your pedals in the attack position, centering your weight over the bike. Gently bounce a few times, then slowly reach down and push the travel indicator against either the shock or fork.
Avoid compressing your suspension by slowly dismounting the bike in the opposite direction. With your air pressure properly set, the travel indicator should move 20-30% of the stroke and about 35% for longer travel applications. Increase or decrease air pressure five PSI at a time until proper sag is achieved.
Now that you have your air pressure dialed, it’s time to set rebound damping. Less damping — turning the adjuster counter clockwise — means the shock or fork will return from compression faster, and vice-versa. If rebound is too fast, you’ll get a skittish, bucking ride. Too slow, and your suspension won’t be ready for the next impact, making for a harsh ride.
The easiest way to get in the ballpark is to use the “top-out test.” Turn your rebound adjust knob so it’s fully open. Now compress the fork or shock as much as possible by pushing down on the saddle, and quickly let go. If the suspension extends too quickly, coming to an abrupt stop at the top of its travel, you’ll need to increase rebound damping to slow it down. Repeat the top-out process on your fork, pressing down on the handlebars instead of the saddle.