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Coolant Temperature Issue??

Reffho

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Hi guys, I have a problem with my FZ6 S2. It’s not overheating, but the temperature is not behaving normally like it used to.

When riding on the highway at around 110 km/h, the temperature stays around 80–82°C. However, as I increase the speed, the temperature starts rising to around 90°C. Even though there is more airflow through the radiator, the temperature keeps increasing.

When cruising steadily at around 130–140 km/h, the temperature reaches around 92°C. When I stop and let the bike idle, the temperature stays around 102–104°C and doesn’t come down, even after the radiator fan kicks in.

I have already flushed the coolant, bled the system, and made sure there are no air pockets, but the temperature is still the same.

Could this be a radiator cap problem or a faulty thermostat?
 
Your coolant temperature sensor (on the back of the cylinder head) could be faulty.

Look in the Yamaha Service or Haynes manuals for the procedure to test it.
 
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