Instructions: Air Fork Operation

Identifying Airfork Controls

Facing the front of the bike:

  • On the left side of the fork there is a blue lock out knob.
  • On the right side of the fork there is a silver or black cover.  Under that cover is the air pressure valve.

 air fork lockout knob

Lockout Operation

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)

air fork lockout knob operation


Setting Sag

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.


Step 1: Remove air pressure valve cover



remove air fork 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.



air fork attach shock pump



Step 3: Wrap a zip tie around one of the shock stanchions.



wrap zip tie around stanchion


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.



rider on bike


Step 5: With the rider's weight still on the bike, move the zip tie down against the fork seal.



setting sag zip tie 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.



measuring air fork sag