Gut the airbox, jet the mains down to 440. Gear to 25/42. dk. blue/white, or almond/blue primary spring, 10-68 weights, blue/orange secondary #2, and a HSP38X helix. 7700 rpm off the line, up to 7900 max top end. Verify the clutch alignment, belt deflection, primary sheave clearance at .020". Also verify the throttle cable and throttle stop adjustment so that the carb slides clear the bores completely at full throttle. Has the CDI update been done? The ves should be changed to stainless, and the springs to green/yellow if 0-1000ft, orange/white if 1-2000ft.
What pockets said.
Especially the gearing, will help enormously, I have the same sled, been there done that. Maybe 24/43 if you really want a twisty trail corner to corner machine and should still see 100 mph but thats all. You'll need studs. Hang on!!
Sounds like your immediate concern with no mph/power is sticky exhaust valves, check them first.
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