Suspension - Setting Sag

Sag is always important, and often over looked. Incorrectly set sag not only effects the performance of the shock, but also the forks because the ride height in the rear changes how the weight of the bike is transferred to the forks. Rider sag is the measurement that should always be set; "free sag", or "static sag" is considered a "check" measurement to make sure the correct spring rate is installed. When your suspension was returned to you the correct rider sag measurement was listed in your paperwork, if you have any questions or concerns don't hesitate to contact us.

Proper Measurement

We recommend the use of two solid (preferably metal) points to measure from and to (shown as A and B in blue below).

We do not recommend measuring to the edge of the plastic fender or side plate, plastic flexes when the bike is lifted off the stand.

Ideally both these points (A and B) follow the arch of the swingarm as shown in red. Measuring too far outside this arch can result in the measurement being off by as much as 15mm.

Factory Connection Sag image

On most models under the rear fender there is a bolt within this arch that can be used as a good point A.

Measuring point B can be any square edge on the back of the swingarm.

Basic Steps to correct sag
  1. With the bike on a stand, and the rear wheel off the ground using a regular tape measure take the first measurement between points A and B. (Extended Length Measurement)
  2. Set the bike on level ground, be sure the gas tank is at least 3/4 full.
  3. With one person balancing the bike have the rider (wearing at least their boots and helmet but ideally all their gear including any tool belts etc..) sit in a natural riding position; like they are riding through the pits. Do not hold either front or rear brake, and make sure the bike is in neutral
  4. Bounce the bike up and down several times and let it settle. Take the second measurement between points A and B. (Rider Sag Measurement)
  5. Have the rider get off the bike and measure from point A to B again. (Free Sag Measurement)
  6. When rider sag is set correctly, the free sag measurement being in the accepted range indicates that the proper spring rate is installed. For more information on correct rider sag and the related free sag numbers for your model please contact us.

Measuring

  Extended Length Measurement (1.) - Rider Measurement (3. & 4.) = Rider Sag
  Extended Length Measurement (1.) - Free Sag Measurement (5.) = Free Sag

If you are looking to determine the proper spring rate… please call Factory Connection and we will be glad to make a fork and shock spring recommendation based on your: Height, Weight, Bike make/model/year and the type of riding you do.