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I just recently got a 1998 vtr1000f from a buddy who had it traded to him in exchange for mechanical work on his car. I'm in the middle of restoring it, as it had been street fightered and then sat for 8 years. It was overheating a bit, and I noticed that the fan wasn't coming on.
I removed the right side radiator to take a look at the fan, and it appears as if the previous owner had done some stuff with his wiring.
There are two wires coming off of the fan motor.
One of the wires connects into the fan motor switch.
The other one connects to nothing.
There is no ground cable.
The two pin connector that is supposed to be mounted on the right side of the radiator is missing.
Temperature gauge does not work, looks like the wire was cut and the previous owner had wired up his own gauge, which is no longer there.
I tried grounding the loose cable that is connected to the fan motor, and I blew the fan fuse.
There are two wires coming off of the bike that are near the radiator, I tested them to see if they were for the front turn signals, and blew the fan fuse again. One of these wires are green, and the other is black with blue striping.
I bled the coolant so that is not the issue.
As far as the gauge goes I just plan on wiring up my own inline gauge for temperature reading.
I just want to get this fan working, either with a manual switch, or with a sensor automatically turning it on, but I'm not quite there with the wiring knowledge, so I'm hoping you guys can give me a hand in this. Anyone have any more troubleshooting steps to try or any tips or guides on the wiring?
The fan wiring (black/blue) is always live from the fuse when the ignition is on, goes to the motor then black to the thermoswitch on the radiator, then to ground. The thermoswitch just completes the circuit to ground when the coolant is hot.
If you want to trigger the fan manually, connect the motor to the black-blue and then put a switch between the other motor terminal black wire and the ground green wire.
Blinker wires are orange or light blue (depending on L or R), plus a green ground. Marker lights (if you have them) in the blinkers are orange/white and light blue/white
Perfect, thanks! I'll try that out once I get home from work tonight. Just for a little bit of clarification on setting it up manually, I connect the wire that's coming off of the fan motor and not currently connected to anything, to the black-blue wire, correct? And when you say the "other motor terminal black wire" are you referring to the wire that connects the motor to the fan motor switch? or are you talking about the ground wire that is supposed to be on the fan, but isnt?
OK to clarify, you should have a black/blue and green wire connected to the harness, and a black/blue and black wire connected to the fan motor. Join the black/blue wires to give a 12v positive feed to the fan motor. Complete the ground path by connecting the black wire to a switch and from the other side of the switch to the green wire.
Be aware the fan switch is totally separate from the temp sensor for the gauge. That sensor is on the left side of the bike on the thermostat housing. The fan switch only grounds the fan at like 200 degrees or around there. It just grounds the fan.
I would recommend not relying on a switch since if you forget the motor could be destroyed. If you are paying attention to it you'll probly crash since riding a bike safely should take all your attention.
Just my experience.
I have mine on the fan switch and a manual switch just in case.
Be aware the fan switch is totally separate from the temp sensor for the gauge. That sensor is on the left side of the bike on the thermostat housing. The fan switch only grounds the fan at like 200 degrees or around there. It just grounds the fan.
I would recommend not relying on a switch since if you forget the motor could be destroyed. If you are paying attention to it you'll probly crash since riding a bike safely should take all your attention.
Just my experience.
I have mine on the fan switch and a manual switch just in case.
THAT ^^^^^
Yes I have a manual switch, but is an override switch so i can get the fan on BEFORE the tempo switch closes and turns on the fan>
I live in Texas, it gets hot here in the summer, if I find myself in traffic, not moving... I can flip the switch and delay the very high temps that will eventually build no matter what as the motor and cooling system heat soak and reach the fully capability of the cooling system.
My winter project will address this with bigger Radiators and a second fan
Ideally I would like to not rely on the manual switch, but I'm fine with either option, I just need a fan that works haha. I wasn't able to test it last night, but does anyone know if there is a way to test the fan motor switch? Does it operate similar to a thermostat where I can just put it in boiling water and see if it closes?
Ideally I would like to not rely on the manual switch, but I'm fine with either option, I just need a fan that works haha. I wasn't able to test it last night, but does anyone know if there is a way to test the fan motor switch? Does it operate similar to a thermostat where I can just put it in boiling water and see if it closes?
Yes in fact that is the method you will find in the factory service manual (you have found and downloaded that from our site..yes?)
There are also lower temp fan switches, like 180*. But when I had one the fan ran so much it was hard to make batteries last.
Honda knew the bikes run warm and the fan does keep it within spec. Its very hot here in NYC and you rarely go fast enough to keep it cool. I went with the ebay Chinese "racing" rads. They cool way better.
I have a write up in here somewhere. Also be sure your thermostat is in place and working. If its always open the water flows too fast and doesn't cool the motor. I have extensive testing to prove this.
08-30-2017, 05:30 PM
Fan Wiring Issue
