81 550 Maxim clutch slippage?

6800 miles orig. When in sixth gear and going up a decently slanted hill with full throttle I will be getting around 5500-6000 rpm and it starts to feel like its going slightly off and on trying to catch itself quick. If i let off of the throttle a tad it will stop slipping. I thought about maybe the carbs needing redoing and maybe it was running too lean? I'd also like to ask, If I am cruising and my bike slips into neutral instead of just shifting to 2nd, when I go to shift to first, if not shifted hard enough it will start ticking off of gears instead of going down into first. Any info would help thanks.