over heating problem?

Question

I have a 1992 kawasaki kx 125 and i have a sever overheatign problem witch when i ride it it overheats and antifreeze comes out of the radeator ... the raderator is alittle beat up but i never had this problem.. i have 2 racing seasons on her (yes i still race a 1992) and im cluch is fully engageing but i posibley need a new one .. the engine gets so hot you cant even hold your hand on the motor for 1 second after getting burnt through the gloves. I really need advise because i love this bike and me andmy step father built it . so. plz if you have advise plz share.

Answer 1

Drain the coolant and remove the water pump cover.
Try to turn the water pump impeller by hand - you shouldn't be able to, unless the engine is turning.
If you can - find out why.
Remove the spark plug and kick start the engine - the water pump impeller should turn.
If it doesn't - find out why.
Remove the hoses from the engine and blow into them - you should be able to.
Otherwise part of the radiator is clogged.
Try blowing through the engine's cooling ports also, to check for blockage.
The bike doesn't have a fan, so the only way for the coolant to stay cool, is by riding the bike, allowing air to rush through the radiator fins.
If the radiator is beat up, it's possible not enough air is getting through, to cool the coolant.
The engine is going to get very hot while the bike is not moving.
That's normal with water cooled dirt bikes.
It's possible the radiator filler neck (where the radiator cap is) is dented, not making a good seal with the radiator cap.
That may be why the coolant is over flowing.
The radiator cap's relief spring may be worn out - not strong enough to hold the pressure of the heated coolant.

Answer 2

Okay, a two-stroke water-cooled dirt racer! Very nice. I suspect your radiator has taken one beating too much. It sounds as if you have no coolant circulating through the engine (as apposed to very little). Cheapest bet would be to replace your thermostat, next up would be water pump, and at the top replace your entire radiator to include hoses and thermostat. Could use some more information though....