Brick is correct. Cogent Dynamics are experts on DR650 suspension and have the parts and knowledge to help you set it up properly. I have built 2 DR650's over the last 2 years and after what I learned on the first one, upgrading the suspension front and back with Cogent's shock and their fork internals was the first thing I did with DR # 2. Not cheap, but not terribly expensive, a bit over $1k and once you are done, you have the best and you will appreciate the improvement for as long as you have your DR650.