Because when you use a short stroke shock on a long travel bike, you need very high spring rates (either from a coil or air shock) for typical sag. When I put a Cascade link on my Levo (55mm stroke), it went up from 150mm travel to 162mm, and required me to go up 75# in spring rate on my coil shock to get the same sag. I don't recall what my air pressure was before, but with an air shock I'm now at 215 psi for a 170 lb rider. If I was a typical fatass ebike rider, I'd...