Are you sure your tach is reading right? 3000rpm wouldn't even be enough to keep the clutch engaged, especially at that weight and with a champ kart. If you were that close to the leaders time there is no way you are only turning 3000, especially if the clutch locks up and the kart takes off. I didn't know bully made a Turbo clutch that was single disc, I believe the Turbo is only 3 or 4 disc. You really need a 2 disc or 3 disc for champ kart and heavy weight like that, or it will just overheat the single disc clutch real quick and that can cause it to slip alot.