If I understand correctly, the engine is running fine but the machine won't accelerate through sustained high RPMS.
If this is accurate, then something is slipping, or the CVT isn't adjusting under power and remains "in low gear".
If the CVT is changing ratios under power and the belt isn't slipping, then you have to take a look at the wet clutch.
What type of oil did you put in the engine after you removed all the water?