AberdeenBikers

The coolant fan seems to have stopped working on my bike, temperatures climbing to 100 - 102 C. Not gone any higher as I can usually get moving which brings it back down.

Does anyone know if I can change the temperature sensor and/or fan without draining the coolant?

My bike hates sitting in traffic and the temp goes right up to 105 degrees before the fan kicks in. I try and avoid town as much as possible but sometimes I think that my engines getting fried. As soon as I get going again the temp drops to about 80.

Not a help to your problem I know, but just thought I would say.

The fan switch is has the sensor submerged in the coolant so you will have some come out when you remove it, how much depends on where it is.
Check all the electrical connections before replacing anything.
You can jump the fan off the battery to check its working alright, if it is working and its still getting V hot without cutting in, check for resistance with a multimeter, at the switch when hot, if its still open circuit its knackered.

The fan on the YZFR6 does not start up untill 105 or 106
It has always been like that since new.
I would not be too worried about the fan not starting at 102 unless it used to start at a temperature below that .

Another thing to check is if the fan can freely rotate as stones and other road crud can get jammed up between the fan and the rad, stopping it from working.

The SV has a fan?

.... It has two...so that means its unlikely its the fan at fault, as one would still work.

Must be a sender unit I would have thought.

Backs 400 wrote:.... It has two...so that means its unlikely its the fan at fault, as one would still work.

Must be a sender unit I would have thought.

Mine has only one fan - someone must have knicked the other!

Fiddled with the sensor connectors and got it working - comes on at 101 °C. Must have been knocked in the fall(s) I had.

Thanks for the repsone though guys. I'll know what to do if it fails properly.

R

One? eeeek!..its more likely somone has sneaked another into the bike outside

Newish one, might have been a change on new models?

Don't just stick into boiling water and check to see if its open circuit or not most sensors are open circuit and then close to make the circuit when they reach the correct temperature ie around 105 degrees on most sports bikes.The best thing to do is hold by a piece of string in a pan of water on the cooker and let it boil to above 100 degrees while checking for a circuit with a meter better if theres two of you After a few years the contacts in the switches begin to break down and the point at which the fan cuts in rises I had problem on my old ZX7R tested the sensor found it was working but the coolant was boiling out of the expansion bottle ,changed the sensor and the fans started to cut in at the correct temperature