Looking for some help here bike 2000 cbr f4 the other day i was on my way home from work and bike was getting hot when under power and cool when comming to a stop i know completely backwards checked coolant thought maybe it was low but no coolant right at the cap no leaks that i can find thermostat is working water pump is working kinda lost now any suggestions

 

Flow problem. How do you know the the pump and thermostat are working?