I am super happy with he shocks setup as it stands. Based on the riding we did this past Saturday, we were able to test two entirely different damping arrangements with Eric's shock being a small modification over the last generation as well as being calibrated for his weight. Eric had spent time riding my bike before this and that gave he and I both a feel for what changes I needed to make.
Eric, if you don't mind, please let me know what could make the shock feel better to you at this point. I also would like clarification on what you describe as "slowing down" on washboard. With me on the bike, I notice that the rear end takes a site "set" or squats just a very small amount but accelerates smoothly and controlled at full throttle while cornering on a gravel washboard road, even up or down hill. (this tends to be an easy to find "test" condition around here!)
The rebound adjustments we made to Eric's shock involved turning the new adjustment knob that is located at the bottom of the shock by 4 clicks. This adjustment was mad with a riding gloved hand while the bike was on the side stand and running at the side of the trail. At that point the shock felt so good, I choose to not make any additional adjustments. The stock compression adjuster screw that is located on the right side of the bike and was left at the mid point. These adjusters have some control over the way the shock responds to sharp bumps or the "high-speed" movement of the shock.
We also spent time checking wheel rate as well as spring rate and have developed the opinion that the stock 6.5 KG spring is good for riders up to 200 lbs or so and that a larger rider will be better served by a spring closer to 7.5 KG (200-250 lb rider). The spring rate recommendation can change for riders of 20 lbs or so either side, dependent on their preference and riding style. (rider wights WO gear).
There is no problem fitting the Eibach Jessie spring to the shock and we have two customer DR shocks in this initial build who will be having those installed.
Cogent Dynamics Inc.