Hi Bob, I guess I was a bit cryptic....only because Cogent Dynamics has come up many times on some other RX4 Forums. Here's a link to their shop:
https://www.motocd.com/
They built the shock and spring to work with my weight (195#) and type of riding. I stressed that I am more interested in compliant suspension than Baja bashing. Due to the limited travel of the shock (because of the linkage used) I imagine they had to tinker a bit so the suspension worked smoothly over both highway and potholes. The end result was a huge improvement. I have a 31" inseam and the shock compresses a bit when I sit on the bike. I cannot flatfoot at a stop. Oh, part of that problem is due to the Russel Day Long saddle adding a bit of height to the seating position.
Call Cogent, mention my name and that you have a RX4. At one point we talked about possibly re-working the OEM shock. I'm not sure if that ever got off the ground. Best of luck.
Peter Y.