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For anyone who wants to replace a radiator ground or fit a manual fan switch

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Posts : 398

For anyone who wants to replace a radiator ground or fit a manual fan switch

Post by liverpool_f_ on Tue 26 Apr 2016, 9:49 am

Hi all,

My bike has never had a working thermostatic fan switch and now does after a bit of a wiring project so I though I would share for those wanting to do the same thing. Firstly, thanks to everyone who answered my questions in my other post. All that info pointed me in the right direction so it is greatly appreciated.

1. My bike had a broken ground tab for the radiator and a very rusty fan mount bracket as many cb's have, so I decided to leave those be for fear of disintegration. Step 1 was to make a new ground, which I did using the engine casing. Since I was also installing a manual switch, the new ground connected the engine casing to the bolt that holds the side panels to the radiator on a non-fared model to the ground of my switch on the dash. I used eyelet connectors to connect the wires to the bolts to keep it all secure and tidy. Sand down the radiator a little to remove any paint or debris for a good ground connection there.

2. The live wire from the fan had had the connector previously removed on my bike, so extend the wire if necessary and run it to the thermostatic switch. At the same time, run another wire from the thermostatic switch to the dash for your switch. Drill the hole in the switch a little larger if needs be to fit both wires in there.

Also note that if your switch is broken like mine was, you can swap it out without draining the cooling system. Loosen it, and when it's almost out, swap them over really quickly. You will lose almost no coolant. Do this when the bike is cold. The coolant will be boiling temperature otherwise and you will risk a very nasty burn.

3. Finally, the two wires that you have run to the dash just need wired into a standard switch. Doesn't matter which way round. Handy tip is not to cut your wires until after you have run them neatly and cable tied them. Hopefully then there will loads of slack left and you can cut them and solder in your switch. I put mine in the fairing as it is easy and  has good access whilst riding.

One last point. Use heat shrink on your connections to keep your cables secure, protect against corrosion, keep them isolated and keep your work looking neat. Don't forget to put it on the wires before soldering you connections!

Thats about it. This is not as neat as the factory solution so is not good if you have tango-esque beauty queen bike but I imagine many people on here do not. It is super effective and still as neat as any other solution is going to be. Both your thermostatic and manual switch should work independently. You can even spin your fan up in the colder months to give it a bit of exercise and to check it still works.

Posts : 2535
Location : Woking, Surrey

Re: For anyone who wants to replace a radiator ground or fit a manual fan switch

Post by teamster1975 on Tue 26 Apr 2016, 2:06 pm

Great job, thanks for writing that up!

    Current date/time is Sun 24 Jun 2018, 11:48 am