just been washing my bike from Sunday and while I was checking it over with the engine running, the fan didn't come on. Is there any way of bypassing the thermostat before I spend money?

Don't quote me on this, and if anyone knows better please chime in, but the thermostat is just a switch that makes a connection when a certain temp is reached, so if you disconnect the thermostat and just use a piece of wire to make the connection at the plug the fan should come on, certainly long enough to test it I would gave thought

ok, next question...where about I the thermostat on these things!?

Thermo on the ossa is directly on the cylinder head, brass thing that screws in, leave it in and trace the wire back about 5 inches to where it plugs into the harness, this is where I would suggest jumping it to trigger the fan, however ad I said before I have no idea if this will work

Hi from a new member.

Had to register to share this info with you , the information below is from Ossa uk ssdt check list. Looks to me like jumping the connecter is a bad idea......

" Check coolant and ensure fan cuts in and out (IMPORTANT) the ossa use a water temperature sensor not a thermostat if your fan stops working dissconnect the block connector from the water sensor that comes out of the cylinder head, the fan should now work (DO NOT BRIDGE THE WIRES THIS CAN CAUSE MAJOR DAMAGE TO YOUR ECU WHICH MAY PUT YOU OUT OF THE EVENT)."

Hopefully this has been helpful

There you go! Thanks Gav72 for the clarification, good job I prefaced my original post with "Don't quote me on this, and if anyone knows better please chime in"....

So by the sound of above I wonder if the fan will just come on immediately once the thermo is disconnected?

Cheers Canada, had some good info from the forum in the past so I'm glad i could give a little back.

Yes sounds like the fan will run constant, worth trying that manx before you order a temp sensor in case your fan is the culprit.

Also check the wiring at the connectors, the reason i say that is i recently had a broken wire at my tps connector caused by very slight corrosion.

turns out I was the relay that has been causing the issue. New one to be ordered this morning.

Another useful tip.... My fuel pump has packed up after 185hrs use, took it apart, and the armature bushes have worn out. Bit of research revealed, the pump is used on a lot of bikes, mainly Yamaha YZF models. Available on eBay from £28.75. Works perfectly.