There is a series of adjustments that should be made to see if your Moto-Cross Bike is set up for you. After a pre-ride inspection and then again after initial break-in. First and foremost among these are the rear suspension race sag adjustments. Setting your shock spring pre-load sag according to the guidelines will ensure correct adjustments and spring selection.

A. The first step toward determining proper suspension adjustment is to set the rear spring pre-load so that the proper ride  height or race sag measurement is achieved.

B. First measure the unloaded dimension (bike up on work stand) Point A to Point B.

C. Measure the loaded dimension   with the rider aboard. Point A to B. Steady the bike upright, put both feet  on pegs. Bounce on seat a couple of times to overcome any stiction.

The race Sag is the difference  between the unloaded and loaded measurements. (24"-20" = 4" of      Race Sag.)

Standard Race Sag for most 125, 250 or   500 Motocrossers is 100mm (3.9).

D. Adjust spring pre-load as necessary to obtain the correct handling results. A race sag setting of 90mm (3.5"), improves turning for tight tracks. Setting the sag to 110mm (4.3") improves stability on faster tracks with less turns, but reduces turning.

WHITE LINE

VERY IMPORTANT

E. Determining if you have      the right spring. Next you need to compare the rear suspension sag under the weight of the motorcycle ONLY - No Rider, No Stand! Measure point A        to Point B. (This is called       static sag.)

Static sag is the difference between unloaded and weight of motorcycle only (24" - 23.25" = static sag).

After setting the spring  pre-load to obtain the proper race sag of 100mm (3.9") the suspension should have .5" to 1" of static sag.

Here is a perfect example with the rider on motorcycle under loaded position. He has 4' of race sag and has .75" of static sag with no rider on motorcycle. The spring has not been over-tightened or under-tightened to achieve the 3.9" of race sag and .75" of static sag.

F. After Setting the spring pre-load to obtain the proper race sag and the bike sags more than 25mm or 1" the spring is too stiff for your weight. (You have backed the spring off too far to get race sag). Now if your static sag is less than .4", the spring is too soft for your weight, requires too much pre-load to achieve the proper race sag and makes the rear top-out when rider dismounts. (You're too much into spring to get static sag).

Keep in mind that a properly adjusted suspension system may bottom very slightly at least once per lap at full racing speed. This knowledge, combined with these adjustment guidelines and those at Shock Therapy Inc on damping adjustment will give you a suspension system that's adjusted as well as any factory rider's motorcross bike.