Total Riding Weight: ( pounds ) includes the rider and anything else added to the bike: lock, water bottles, etc.
Rear Weight Bias: ( percent ) The standard formula is based on a 60:40, Rear to Front weight distribution. A more accurate way would be to use a bathroom scale under the rear wheel and a 2x4 under the front wheel to determine the true sprung weight at the rear wheel. Position your body according to your riding style. Enter this value for total weight and 100 for Rear Weight Bias. Alternatively use 55=XC, 65=FR, 70=DH, all others use the standard 60.
Rear Wheel Travel / Shock Stroke: ( inches )
Shock Sag: ( percentage of shock stroke ) The standard formula uses the Fox Shox recommended 25 of shock stroke. A zero-preload spring rate is determined, then preload is applied to calculate the corresponding sag. Choose a sag appropriate to your riding style. If you are an extreme rider ( jumps, drops, big hits, etc ) you should run less sag and a correspondingly higher spring rate.
Preload Adjuster: ( number of turns ) A minimum of 1.0 is required.
End-Coil Effect: ( percent ) Closed/Ground compression springs have a typically lower spring rate in their initial deflection range. The canned value is a best guess of the effect ECE will have on preload adjustment. It is a percentage of the overall spring rate used in calculating the spring tension for the specified turns of preload.