Operation Manual

16 COOLING SYSTEM 99
16.1 Cooling system
V00373-10
(All 125/150 models)
Water pump

in the engine circulates the coolant.
The pressure resulting from the warming of the cooling system is regulated by a
valve in radiator cap

. This ensures that operating the vehicle at the specified
coolant temperature will not result in a risk of malfunctions.
120 °C (248 °F)
Cooling is effected by the air stream.
The lower the speed, the less the cooling effect. Dirty cooling fins also reduce the
cooling effect.
V00374-10
(All 250/300 models)
Water pump

in the engine circulates the coolant.
The pressure resulting from the warming of the cooling system is regulated by a
valve in radiator cap

. This ensures that operating the vehicle at the specified
coolant temperature will not result in a risk of malfunctions.
120 °C (248 °F)
Cooling is effected by the air stream.
The lower the speed, the less the cooling effect. Dirty cooling fins also reduce the
cooling effect.
16.2 Checking the antifreeze and coolant level
Warning
Danger of scalding During motorcycle operation, the coolant gets very hot and is under pressure.
– Do not open the radiator, the radiator hoses or other cooling system components if the engine or the cooling system are at
operating temperature.
– Allow the cooling system and the engine to cool down before you open the radiator, the radiator hoses or other components
of the cooling system.
– In the event of scalding, rinse the area affected immediately with lukewarm water.
Warning
Danger of poisoning Coolant is toxic and a health hazard.
– Keep coolant out of the reach of children.
– Do not allow coolant to come into contact with the skin, the eyes and clothing.
– Consult a doctor immediately if coolant is swallowed.
– Rinse the affected area immediately with plenty of water in the event of contact with the skin.
– Rinse eyes thoroughly with water and consult a doctor immediately if coolant gets into the eyes.
– Change clothing if coolant spills onto your clothing.
Condition
The engine is cold.
400243-10
– Stand the motorcycle upright on a horizontal surface.
– Remove the radiator cap.
– Check the coolant antifreeze.
−25… −45 °C (−13… −49 °F)
» If the antifreeze in the coolant does not match the specified value:
– Correct the coolant antifreeze.
– Check the coolant level in the radiator.
Coolant level

above the radiator
fins
10 mm (0.39 in)
» If the coolant level does not match the specified value:
– Correct the coolant level.
Coolant ( p. 141)