by: TheRepairMan


My project for adding the Torqflo Adjustable Cooling Fan Controller is complete. It works VERY well and has solved the problem of this bike blasting 212° to 216° air onto my legs when the fans kick on. This helps reduce the overall heat output we are exposed to from our bikes.

It has never made sense to me that the Coolant Thermostat normally begins to open at 160° F and the fans don't come on until the coolant gets to 213°+. This will make it possible to lower them by at least 20°. Not enough to cause the ECU to go into open loop. We don't want the engine or the oil to run too cool. Just cooler.

This secondary fan control system simply runs parallel to the factory system and supplies fused power directly to the fan circuits when the fully adjustable temperature setting is satisfied.

It is a redundant system and should one fail the other will still be operable as long as the bike's fans and fan relay are in normal working order.

The task is rather lengthy so I have compiled as much info and photos as I can into this first post.

If you are capable of successfully installing an FCE or other electronics on your bike this will be just about as easy. I'll try to explain each step as clearly as possible.

There is still some good discussion found in the original thread. I highly recommend reading it all thoroughly before you start your project and printing off what you need.

Note that I will not be disabling the original factory ECU control over the fans as a safety precaution. The electronics in the Torqflo Adjustable Cooling Fan Controller supply power (+) to the bike's fan wires at the fan relay when activated, not ground.

Here are the installation instructions for this solid state controller that makes the fans come on at lower temperature settings of your choice.

Step #1:

Okay, this is the kit I'm using. It's a sealed solid state unit with a completely replaceable commonly found automotive accessory relay, and a tiny adjustable rheostat built into the processor. Turning this variable control setting will set the opening and closing points for the relay letting you tell the processor at what temperature you want the fans to come on.

Here's what's included in the kit, and a little more about it...


I was able to obtain a nearly identical kit from my local automotive parts store (AutoZone's Torqflo brand) for less than $40.00.

Jegs has the same unit available on line.


They also have many other options and kits.


OKAY, before you start your project...

...You will need a few wiring connectors and some split flex tubing for conduit, a roll of electrical tape, some small wire ties, basic electrical crimping tools and a little patience and some basic tool skills wouldn't hurt any.

*Adjustable activation screw sets fan activation anywhere from 150° to 240° F. The unit is set at 160° F from the factory.

*Thermostatic probe inserts into fins in the radiator core.

*Includes 25 amp push-in style fuse.

*Comes with some of the necessary mounting hardware, butt connectors, terminals and a fan lead wire splicer if you are running dual fan set up.

You will also need to obtain a few of these "wire taps" to make the job of making a "T" wiring connection much easier rather than cutting and re-splicing in several points.

14-16ga Mid Wire T-Tap

18-22ga Mid Wire T-Tap

14-16 ga. 1/4" Fully Insulated Male Quick Connect

A few feet of 3/8ths Inch Split Wire Conduit and a handful of 6" plastic wire ties.

Step #2:

Locate the bike's cooling fan relay. (see illustration below) It is rubber mounted on a plastic tab directly below the front seat catch and right beside the bike's fuse box opposite the (+) post on the Battery.

Step #3:

This is how to make connections for the Torqflo Adjustable Cooling Fan Controller.

There are four wires in the bike's fan relay, two small gage and two larger. Being very careful not to cut into the four wires, roll or cut back the conduit or boot about an inch to expose all four insulated relay wires.

Now locate the larger Brown wire with a green tracer going into the relay and install a wire tap. This is the blue saddle type that slips over the wire and taps through the insulation without cutting or damaging the wire. It will allow you to connect to it with a push on male connector.


Connect the heavy gage Orange wire from the Controller to the Brown wire with the green tracer going into the bike's fan relay.

See the large solid orange wire and tap below. That is the fan power from my controller to the fan motor circuits.

My adjustable fan controller installed at the left front corner under the pillion seat. Wiring not run yet.

The aftermarket temp probe in the kit fits into the fins up against the radiator end tank just below the upper radiator hose just perfectly, and couldn't have been easier to install. Just a wire tie around the probe and the fan cage holds it in place.

Locate the bike's "Starting Circuit Cut-off Relay" in line to the starter system wiring. The normal operation of this relay is to cut power to the Headlight and Cooling fans during engine cranking (key in start position) only.

Here is the diagram instruction page as well as the final steps to follow below.

Step #4:

This last step takes a bit of determination to complete.

Connecting the Adjustable Fan Controller's yellow wire to the blue wire with a white tracer in the second terminal position of the Starting circuit cut-off relay connector.

Okay, here's the back side view of the connector and the circuit diagram of the "Starting circuit cut-off relay".

Of the top row in the connector, you have to back probe one of the blue and white wires with a test light.

It will have power to it with the bike's key turned to the "run" position and will NOT be powered up while you crank the engine.

When you hit the bike's starter button your test light will momentarily go out.

This is the blue/white wire you will connect the "Yellow Ignition Source" wire from your fan controller to.

Finding that circuit was a little time consuming but at least I didn't have to add another relay.

The following instructions will help you find the exact location of the "Starting circuit cut off relay" and how to locate the last wire in the project.

Now you have to keep in mind this isn't air conditioning! That 180° to 190° air off the radiator is still hot, and I have yet to mount a fan under the seat to help move a little fresh air into that area, but something had to be done to keep my bike off of that 212° to 216° mark and so far this is working very well.

Pictures of the relay under the front seat latch and my last connection to the blue and white wire at the Starting cut-off relay below. You must access them from underneath the front seat.

There is enough harness to each relay to pull them out of their respective mounts and have room to add the two required wire taps to the harnesses. Removing the latch's two 6mm nuts along with the latch will help to gain access to the "Starting cut-off relay". It is literally directly under the front seat's latch mount attached to a rubber holder over a plastic support tab.

Here the "Starting Circuit Cut-off relay" and the "Cooling Fan Relay" can be seen, but not accessed from, looking from the rear of the bike forward over the tail light just in front of the tool box.

And, finally the finished project.

The new controller works well. It kept the temperature of the engine at 200° or less during the first 20 to 30 minutes of idling, and this is now adjustable.

Yesterday ride in 80°+ outside temps. with half an hour of stop and go traffic never saw the engine temps go above 193°. The cooling fans run a little more often in stop and go traffic, but not when the bike is moving and flowing air.

Engine temperatures during normal highway use are still being regulated by the Coolant Thermostat. Don't worry! No danger of this bike running too cool.

I personally found this project not to be any more difficult than my fender eliminator and tail/turn/marker light project. Actually, probably easier once I located the correct wires on the bike.

I'll be more than glad to answer any further questions as your fan controller project progresses.

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