[underpowered]

the natural moion of leaves causes the need for exta slip.

as leaves droop out, the axle will move forward as well as drop out, both will increase the length of the shaft. when it compresses the axle will move rearward as well as up, both of which shorten the shaft needed. between the two phenomenon alot more slipp will be used with rear-shackled leafs.

with Links, the natural arc helps combat this as the axle does the opposite. as you droop, you axle moves back and down and under compression moves up and forward so the length of slip needed is decreased greatly with links over leaves.