Temp gauge acting up

On the way back today (a very warm day) the temp gauge on the dash wouldn’t go over 83°C. It even went down to 35° when I slowed down or stopped at lights.

The temp gauge in my toes told another story! The bike was super hot!

Obviously was worried that if the temp gauge is incorrectly low then the fans wouldn’t kick in, so I pulled over. But the fans were going like mad.

So it seems that the dash is only at fault! Anyone heard of this before? my ideas what to check?

This is on a CB1000R

Ps coolant is within acceptable levels and was replaced in April during service

could be if the temp sender sensor is different to the fan switch that the sensor is gone. taking that out and testing it used to be a standard maintenance procedure.

Yeah, it sounds likely that there’s two components. One’s the sensor that sends data to the fuel gate, and the other’s a switch that turns the fan on. I suspect the former’s broken and the latter’s fine.

Have you got a haynes manual? That’ll explain how to test the former, if it’s possible to.

I agree the fan kicking in is a good sign…
Had a look at Haynes manual and to test the sensor is a lift tank jobie… Something for the weekend then

Have you got an air lock in the cooling system?

“Have you got an air lock in the cooling system?”
how would i test that?

Turn the bike upside down and give it a good shake maybe?

Do i remove the radiator cap before turning it upside down?

Sorry, was just messing. I think if you pressurize the cooling system you can sometimes clear an airlock. Otherwise it’s dumping the coolant and slowly refilling.

Sorry to OT this thread but LOL

The upside down comment ain’t as stupid as it sounds, the KTM 990 needs to have the front wheel lifted to ‘burp’ the system.

I’m not as stupid as I sound? Never heard that before

thought id update this thread for future problem solving.

the issue was with a corroded and frailed wire under the seat. FWR took no time to find and fix. and they didnt charge a thing!