Gen 1 fan switch

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Chug4life

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Was following a youtube video but when related to mine (2003) the wiring is a differant color code than the video. Is this the wiring i can add a switch to? Disconnected for reference.
 

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2 wires, blue [1] and brown [2] appear to be the correct colors on this to-1989 wire diagram, going to the fan thermocouple. Be sure that one side isn't always-hot, where the fan would run when 'on' even with the engine and ignition off. Many vehicles will continue to run power to the cooling fan when the ignition is 'off,' to cool-down the temperature to a specific point. If the system has an electric water pump, that might run also, even when the engine is off.
 

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Next question, before i splice into the wires can i bridge the connectors with a paperclip first to make sure fan actually works?
 
Yes, connecting together the two connectors on the thermal switch is fine (that's what it does inside) and the fan should turn on.

Check the fan is sucking air through the radiator, I don't think it is possible to wire the fan the opposite way but no harm checking.
 
BTW why do you feel you need to fit an override switch?

If the temperature indicator is getting into the red, then you need to measure water temperature as you cannot assume it is wholly accurate.

Use an IR thermometer for temperature measurements.
If the engine has overheated, then that is indicative of another problem.

Simple things to do.
Flush the cooling system and replace coolant with the correct mix of recommended anti freeze. I skipped undoing the cylinder drain bolts.
Check the stupid plastic drain valve is in the correct position.
Check there is no air lock.
Check connection to battery, fan and switch are clean and fan is pulling strongly.
Check water hoses have not collapsed, the one on top right can get squeezed by the air box.
Check the radiator matrix is clear.
Check the thermostat is opening - not so easy.
Check water pump is a good order, in particular the impeller bladed - even less easy.
 
Cooling system is clean as i pulled it all apart to check starter about a month ago. Combined weight 2 up we're carrying 400lbs ish. In stop n go traffic she climbs beyond my comfort zone and just want added cooling. Will come in handy for cooling down between drag race passes . Nothing is wrong with the system.
 
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If nothing is wrong with the system then why do you feel you need an override?

How likely is it that yamaha did not test the vmax in stop start traffic conditions probably at higher ambient temperatures?

Unless you live on Venus I genuinely don't see why you should have a problem.

I would the engine would reach higher temperatures when stationary the when having its neck wringed out on the strip where there is forced air cooling. A slow ride back would cool it down far quicker than the fan could.
 
If you live a warm region, as I do, I highly recommend this modification. Most factory settings have the fan wait too long before activating. Then it's too late to shed the excess heat. I have seen this happen on a number of otherwise well sorted water cooled motorcycles. In Phoenix in or near summer and in traffic, there is very little margin for error.
 
If you live a warm region, as I do, I highly recommend this modification. Most factory settings have the fan wait too long before activating.

Even if the rate of global warming accelerates exponentially, I won't have that problem. :)

Rather than having to remember to turn on the fan, and off (over cooling isn't good either for an engine but the fan alone ain't gonna do that), can a different thermostatic switch be fitted?

There are switches that turn on at different temperatures as well as switches with two contacts that switch at two different temperatures. The latter are intended to turn on fan at say half speed and if temperature reaches the higher switching point, turn on the fan at full speed.

Ofcourse it all depends on the thread of the switch, there are a few different standards, but I'm sure there will be alternatives.

I have come across a list but would anyone know the thread on the Vmax switch?
 
I've run my Vmax in 100 degree weather in stop and go traffic and never needed a fan switch. I've never understood peoples fascination with it.
 
While so. Florida isn't the southwest in August Death Valley, the Mojave, Bonneville, the Salton Sea, or any other hot-spot/hell, it does get hot to allow the fan to cycle-on. I've never had my VMax or other liquid-cooled Yamaha overheat when the cooling system is up to snuff.

Previously, I've posted lists compiled by others of easily-available thermostats, fan-control switches, liquid coolants, and other aids to cooling efficiency. This includes allowing a different temperature for the accessory to operate. Cost is usually lower too, and because they often are auto parts for Japanese imports, they're less-$. Servicing your coolant every several years helps, and don't use one of those 'Punisher' or nameplate grille covers over your radiator. Use the search function.
 
Might make a 'pictoral' tonight on how to run an aux switch for the fan while keeping the thermostatic switch, double cooling security lol
I noticed mine went about 3/4 warm on the gauge (fan turned on fine) when I had it idling for a few minutes after riding last week. Is that normal? I wonder if I need to service / replace the thermostat and coolant?
 
I noticed mine went about 3/4 warm on the gauge (fan turned on fine) when I had it idling for a few minutes after riding last week. Is that normal? I wonder if I need to service / replace the thermostat and coolant?
Perfectly normal.

Typically, the fan doesn't turn on until right when the needle hits right at the gap between the black and the red area or sometimes right towards the end of the black. If it gets into the red area and the fan isn't running, then you have a problem.

The circled area on this picture is where the fan typically turns on.

Fan turns on.jpg
It's also OK to run in the thin red stripe area for a little while, but if you ever get to that thick red stripe at the end, turn the bike off immediately.

Most people install the fan switch because they think the Vmax is a car where the fan should run constantly. It's completely unnecessary.
 
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Perfectly normal.

Typically, the fan doesn't turn on until right when the needle hits right at the gap between the black and the red area or sometimes right towards the end of the black. If it gets into the red area and the fan isn't running, then you have a problem.

The circled area on this picture is where the fan typically turns on.

View attachment 80498
It's also OK to run in the thin red stripe area for a little while, but if you ever get to that thick red stripe at the end, turn the bike off immediately.

Most people install the fan switch because they think the Vmax is a car where the fan should run constantly. It's completely unnecessary.
Excellent, thank you. Just got the bike, so not sure of what's normal and what's not on it yet.

:)
 
Perfectly normal.

Typically, the fan doesn't turn on until right when the needle hits right at the gap between the black and the red area or sometimes right towards the end of the black. If it gets into the red area and the fan isn't running, then you have a problem.

The circled area on this picture is where the fan typically turns on.


It's also OK to run in the thin red stripe area for a little while, but if you ever get to that thick red stripe at the end, turn the bike off immediately.

Most people install the fan switch because they think the Vmax is a car where the fan should run constantly. It's completely unnecessary.
Check with infrared thermometer, I don't think gauge should go to red. Gauge is bad or switch.
 

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