Stock gearing and stock secondary. I modified a set of E ramps to Aaen spec, and used a red Kawasaki spring. Then adjusted the ramp weights until I got the desired max RPM, being the rest of the sled is stock-ish, 8,000 RPM. I believe for me I ended up with stock ramp bolts with 3 thick washers on each. This gave me a wicked launch, I don't recall the exact engagement rpm, but it made my Invader scary fast. It's an excellent drag setup, but not very trail friendly. I played with the clutch a lot, and ended up with stock. I do keep a clutch setup with the Aaen weights in case I ever get someone that wants to race all I have to do is pop it on.