New Problem!!! Engine sounds fine but bike seems to hesitate?

[tom42]

When I'm riding usually in second or third gear (that's where I notice it the most) and hit the throttle the engine hums but the bike seems to accelerate slowly?  My best analogy would be that of a car with low transmission fluid, but without the sudden shift you get in a car after the torch converter kicks in.  What could this be?  Any help would be greatly appreciated.

Thanks