Fan switch

[KennonNC29]

Fixed the fault now cleaned out the fins that were full of muck and turns out the fan wasn't coming on due to a blown fuse thankfully nice and easy but at some point my bike has been on the ground so the bolts are either odd or the mounts are repaired, have had to do a cable tie fix to the left and right lowers so they join with no gap.

Kennon

[pip]

I've just fitted an override switch, not difficult at all thermo switch opens to earth, so I've ran a switch to earth and switched 12v from the coil live fire, So only works when ignition is on, I also used a illuminated switch to indicate the fan is overridden

You really are better sorting the actual problem....

Why on earth (no pun intended...) Are you switching the fan from the coil live???
The fan positive is switched 'on' with the ignition

Pip

[Neosophist]

I've just fitted an override switch, not difficult at all thermo switch opens to earth, so I've ran a switch to earth and switched 12v from the coil live fire, So only works when ignition is on, I also used a illuminated switch to indicate the fan is overridden

You really are better sorting the actual problem....

Why on earth (no pun intended...) Are you switching the fan from the coil live???
The fan positive is switched 'on' with the ignition

Pip

yes wtf is this.


all you need to do is connect the single wire from the fan switch to earth and the fan will come on (and only when the ignition is on)


You can build an override with one wire.

locate your temp switch on the left hand side and see it has one spade coming out of it.. buy a "piggy back spade"



this will allow you to keep the origianl wire in place but give you an extra tab.

From this tab run a wire to a normal on / off switch. from the other connection on the switch run some wire to earth.

<new tab>-------(switch)-----<earth>

When you turn the switch on the fan will run.

If you dont have the switch on and the temp is too hot the fan will still work.


PS: do not bother with a fan switch, it is maskng some other problem you have with your bike.

They are fine to run hot, the fan should come on when its needed. only if it starts boiling over everywhere do you have a problem.. no need to panick about it being warm.

dont forget that the bike was built for riding around Japan... a country with a speed limit of 60mph and temperatures in the high 30s for 3 months of the year.

not exactly a place to keep the bike cool and they didnt have any issue over there.

[NGneer]

I did this 'fan bypass' set up on one of my bikes ages ago as it was getting very warm when driving through town. In hindsight a good clean of the rads would have probobly done just as well (it was pre-chinese rads being available) but with a new chinese lower on my current bike, it is very rare the bike even gets hot enough to trigger the fan anymore.

Anyway as per Neo's comments above if you still want to do it:

Get yourself a switch of some sort and locate on the bike (I fitted mine into the R/H infil panel).


From the back of the switch there will be two terminals.


Run a cable from one of these terminals to earth. From the other terminal run another piece of cable down to the temp sensor on the L/H side of the lower radiator and fit with a piggy back connector.


Remove the spade conector that goes onto the temp sensor..


Connect original temp sensor spade to the new wire using the piggy back connector, then connect both wires to the temp sensor - Job done.


If you know you are heading into town or such like you can manualy turn the switch on and the fan will run. If you dont have the switch on but the temp gets hot enough the fan will still work automaticaly as designed to do.

[KennonNC29]

I'll probably switch to chinese rads next year mine have been cleaned but are still abit grotty.

Kennon

[scotjell]

Sorry to dig up an old post but what size of cable should be used. I'm trying to fault find as have new rads and want to know if either my fan switches are at fault, fan faulty or if wiring/earth.

[Neosophist]

Fairly straight forward.

Remember the fan doesn't come on until the engine is hot.. sometimes people dont wait long enough.

First thing to do is put the igntion on.

The fan switch has a single wire, if you remove the wire and short the spade that was on that switch to a good ground on the frame then the fan should come on.

If it doesn't then you have a problem with the fan / fan wiring / fan fuse.

If it comes on by shorting it but doesnt when the engine is in the hot zone then you have a faulty fan switch.

You can test it by putting the fan switch into soem boiling water and checking for connectivity between the terminal for the spade connector and the brass body of the swtich after its been in the water for a few seconds.