I have the D&D clutch kit in my 03 F7. It performs very well against the ZR900 of my buddies......same weight and both stock. (I just added a speedwerx single this year, but not expecting much from it.) I new that a lot of the top racers were using the Big Dog weights is the drags when the F7 first came out, and I new that the D&D used them in the kit. I'm not sure about the current kit, but mine works well. Most people on this sight either use the ODS kit, or they have the time, knowledge, and tools to build thier own. I haven't seen a whole lot about helixes and weights and springs, it's all ODS. I would like to race side by side with one just to see the difference. Who knows, maybe I'd get my but kicked, but atleast I would know.