moter slipping at higher rpm

[its about time]

I have a 1981 jhonson 140 hp moter that started sliping at higher rpms, when i trottle it back down to a lower rpm it will continue to move fprward ok, just cant go fast with out feelling like a clutch is slipping in a truck.
i just rebuilt the the lower unit and the clutch dogs looked good. i hear it also may be a spun prop. could any of this be caused by a weak spring on back of clutch dogs?

Since the trouble started befor the lower end rebuild i think i can rule out cable adjustment. any help would be apprecaited greatly

 

[Bifflefan]

Re: moter slipping at higher rpm

Spun prop hub.
Replace it, or you may be idling in on the next trip.