Just got my 99 yzf running again. Had the carb cleaned drained and refilled the gas. The only problem is I am getting a poping out of the exhaust almost like a moisture poping. I am thinking the carb settings are wrong. I also noticed the cooling system is very hot to touch and the overflow keeps on leaking coolant. It is giving me an idea that the cooling system is boiling over. The radiators are very hot to touch. The coolant is flowing so I know the water pump is working. Is their a thermostat on these bikes. I am hoping it is not the head gasket. Any sugesstions?