Sounds like it might just be the clutch. On the right side case, you will see something that says "INCREASE - DECREASE" with corresponding arrows, this is your clutch adjuster. Take a wrench, loosen this nut, take a flat screwdriver and turn the screw to the left until you feel resistance, then turn it 1/8 of a turn to the right. Hold the screwdriver there so the screw doesn't move, tighten up the nut, and you've just adjusted your clutch. Sounds more complicated than it really is, just follow it step by step. Lemme know how it works!
Trikes:
1973 Honda ATC70-orange!
(2)1985 ATC70
1985 Big Red 250
1985 250R