Rear Shock Spring Charts

[rideright]

After reviewing many diferent spring charts out there on the web by many differnet companies, i have noticed a real question as to functionality:

Chart A Company X pick any bike for example '02 CR125

150lb rider = 4.6 rear spring

yet, same bike, same front to rear bias, same unsprung weight, same linkage ratio, all constents of the algerbraic equation the same, same everything, but now use a 225lb rider

225lb rider = 5.2 rear spring

225/150 = 1.5 ratio

5.2/4.6 = 1.1 ratio

something is wrong in my math or there exist a basic inherent variable in everyones rear spring charts ???? :ugg:

 

[terry hay]

The increase in rear spring rate is not linear to the load which makes sense given that we are dealing with leverages. Also you would have to combine rider weight with proportionate bike weight before you calculate ratios as this is also supported by the spring. 200lb bike with 52% RWB = 104lbs plus rider weight on rear spring. Your ratio without other factors would now be 329/254
Terry

 

[rideright]

That helps me to understand a little more, but I think I'm still missing something?