Facing the front of the bike:
Turn the blue lock knob clockwise to lockout the fork (this deactivates the suspension function of the fork)
Turn the blue lock knob counter clockwise to unlock (this activate the suspension function of the fork)
Sag is the amount of compression the fork achieves at rest with the riders weight on the bike. You can experiment with different amounts of sag, but as a starting point on Prevelo bikes, 10mm to 15mm of sag works.
TOOLS REQUIRED: Shock Pump
Step 1: Remove air pressure valve cover
Step 2: Attach shock pump. The shock pump does not need to be very tight on the air pressure valve. It only needs to be tight enough to press the pin in the valve and achieve a seal.
Step 3: Wrap a zip tie around one of the shock stanchions.
Step 4: Have rider sit on bike. The rider should put as much of their weight on the bike as possible, but should not bounce on the bike. A good technique is to have the rider brace them self against a wall or another person. The goal is to get an idea of where the air fork will settle with the rider's weight resting on the bike.
Step 5: With the rider's weight still on the bike, move the zip tie down against the fork seal.
Step 6: Have the rider dismount the bike. Allow the airfork to extend. Measure the distance between the zip tie and the fork seal. As a good starting point this distance should be between 10mm and 15mm. To increase sag, release air pressure using the air release function of your shock pump. To decrease sag, add air pressure using the shock pump.