Another thing I find on a lot of folks bikes is the radiator is completely clogged with dirt, and you can't see through it.
Anytime I service a coolant system, I replace all the O-rings (front cover & t-stat housing) check all the clamps & hoses, remove paint from the radiator pipes if any, flush the radiator out (inside), then soak the radiator in warm water, then lightly spray the fins to remove all the road debris and dirt.
I often find about a 1/4 inch of dirt and sand in the rinse pan afterwards.
You should be able to see light through your radiator.
Anytime I service a coolant system, I replace all the O-rings (front cover & t-stat housing) check all the clamps & hoses, remove paint from the radiator pipes if any, flush the radiator out (inside), then soak the radiator in warm water, then lightly spray the fins to remove all the road debris and dirt.
I often find about a 1/4 inch of dirt and sand in the rinse pan afterwards.
You should be able to see light through your radiator.