I have a 1978 El Tigre 600 440 LC, and I am trying to clutch it. I live at 5000 ft altitude, but ride at 9000 ft and higher. The sled runs OK down here but is doggy and will eventually get hot and bog in the mountains. I geared it down to 20/39, and have the reclutched it. I currently have a yellow/green comet primary spring and 41 gram weights. The Secondary has a 47 degree helix in a reverse ramp secondary with a Black Magic Purple/White Spring( a little stiffer than a stock Cat Yellow spring) My question is what RPM shjould this sled shift at and top out at. In my neighborhood on icy streets last night I had to tighten the secondary spring to the last hole to get it to shift at 7500RPM and top out at 7900-8000 RPM. (It wouild only rev to 8100 with the track off the ground on a stand)I would assume woth the short stroke that the 400 Liquid has it should run somewhere closer to 8500RPM, but not sure. My clutch engages abouit 4500 RPM (5000 RPM if I hold nail it)and I would like that higher to keep her from bogging, but the lack of top end kind of concerns me.