calling all electrical experts:) running a cooling fan?

[jon370r]

How can I make a YFZ cooling fan run off a stock 250R stator? I tried it and there doesn't seem to be enough amps or watts or something to run it. What are my options besides mounting a battery? I do alot of hillclimbs which involve max power with little time or speed to cool the radiator in between climbs.

[Aceman]

I believe 250r's are AC voltage while the YFZ's are DC voltage. I think there is a bit more to it than just hooking the wires up. Maybe Wilkin can chime in and help you out, I've seen him post about this before.

[jon370r]

I was always had the understanding that it was a 12 volt DC system just like any other motorcycle and ATV. I have never herd of a vehicle with an alternator being anything other than DC. The Honda service manual rates the stock output for the lights at 12 volts with 55/60 watts. That sounds like DC to me.

[deathman53]

no, most bikes that don't use a battery are AC power. DC power is only on bikes with a battery. AC comes from the stator, it gets changed to DC on the retrifier. Some bikes are AC and DC, my ktm 450exc for example, AC is for the lights and DC is for the starter and radiator fan.

Basicily(not at all times, with ktm and husky being the two that I know of that are AC and DC), if it has a battery its DC, no battery, its AC.

[jon370r]

Goes to show you learn somethig new every day. So with that settled I need to find a small 12v ac fan. Any ideas where to get something like that?

[deathman53]

a kick start trx450r doesn't have a battery and puts out AC power, that would be a good place to start.

[trailwart]

i was looking in an atv mag not to long ago and in the back adds i remember seeing some kit for a banshee, they had a web site, might be able to use on an r???

[jon370r]

Those are both good leads. Thanks for the replies

[wilkin250r]

I'm not sure how much I can add, it's pretty much already been said.

Yes, the 250r is AC. In fact, ALL quad put out AC directly from the stator, like deathman said, but it gets converted to DC for those models with a battery and electric start.

If you were REALLY creative, you could put together a small rectifier and filter (to convert AC to DC) for the fan inputs, but I wouldn't suggest that unless you already had a strong electrical background.

[trailwart]

found the add, heres the link
http://www.banshee-cooling.com/

[deathman53]

that thing looks like it blocks 1/2 the radiator, I wouldn't use it. Use a trx450r kick stat fan, it looks alot better and do able also.

[jon370r]

The Honda part numbers for the fan motor are the same for both kick and electric start models and its the same exact motor as the YFZ just different fan design, so that won't work. I did find that Trail Tech sells a Voltage Regulator/Rectifier to DC for $35. I don't know if this will work for what I need but I will call them on Monday and ask.

http://trailtech.net/regulator_rectifier.html

[wilkin250r]

That regulator/rectifier may not work without additional modifications.

If you rectify an AC signal to DC, they cannot share the same ground. Typically, when converting a motorcycle from AC to DC, you have to "float" the stator. You have to modify it so the stator does not use chassis ground.

Tell you what I'll do. If you find a proper DC fan that will work for your project, and you double-check the wattage to make sure it will work with your existing system, I'll help you design a simple inline rectifier. (I'm an electrical engineer). That way, you won't need to convert your entire system to DC, just the power that goes to the fan.

[D Bergstrom]

It is not to hard to convert to DC. I have HID lights for my 250R and had to do it to run them. The place I bought the lights from (Baja Designs) made me a wire harness that included a regulator/rectifier and a small battery pack, then everything just plugged in, pretty simple. I do not think you will need the battery pack, as this was needed as I am running two HID's and even a 200 watt stator does not put out enough power at idle, so at low rpm's it can draw off the battery and keep the lights on.

Looks like Wilken has you covered, but if you need it, I still have the wiring diagram that came with my lights, I should be able to scan it and send it to you.

Doug

[wilkin250r]

Bergstrom, did you have to modify the stator? Or did you get a new stator that was already isolated?

[D Bergstrom]

No mods were made to the stator. I am only using one wire of the two used for lights. (I think it is the white one.) The wire harness I got has a ground wire in it, so I just grounded it to the same spot as the stock wire harness. I have attached a copy of the wiring schematic that I got with the lights.

Doug

[jon370r]

I have been doing some research and Baja Designs was another one that I had found that might have what I'm looking for. Sounds promising. I went out for a 2hr. ride yesterday and typical slow trail ridind my 401 engine was running around 190-210 degrees, but would keep climbing in temp when I beat on it. I got the YFZ fan assembly to fit perfect just need to get power to it. Thanks for all the input guys.

[wilkin250r]

Originally posted by jon370r
I went out for a 2hr. ride yesterday and typical slow trail ridind my 401 engine was running around 190-210 degrees, but would keep climbing in temp when I beat on it.

What kind of coolant are you running?

[jon370r]

I have tried Engine Ice and Wetter Water and didn't see a big difference so I'm just using 1/2 antifreeze and 1/2 water now.

[jon370r]

Originally posted by D Bergstrom
No mods were made to the stator. I am only using one wire of the two used for lights. (I think it is the white one.) The wire harness I got has a ground wire in it, so I just grounded it to the same spot as the stock wire harness. I have attached a copy of the wiring schematic that I got with the lights.

Doug

You wouldn't happen to have the Part number of the kit they sold you? The guy I talked to was very unsure of the application on a 250R, but id does sound like they will have something that will work.

[D Bergstrom]

Originally posted by jon370r
You wouldn't happen to have the Part number of the kit they sold you? The guy I talked to was very unsure of the application on a 250R, but id does sound like they will have something that will work.

I do not think there is a part number. They put together the harness for me, asked me where I wanted to mount the battery and regulator/rectifier so they could make the wires the right length. (They are both in my airbox.) I bought everything about two years ago. The wiring schematic is from them, you would think that they would have it on file, and they would know what you are talking about. My experience with Baja Designs is that there are some very smart people that work there, unfortunately, the people who do not know much are the ones who answer the phone. If you have any other questions, feel free to ask.

Doug

[wilkin250r]

Originally posted by jon370r
I have tried Engine Ice and Wetter Water and didn't see a big difference so I'm just using 1/2 antifreeze and 1/2 water now.

When/how did you try Water Wetter? Did you do it alone, or with antifreeze?

I was involved in designing a water-cooling system for network servers several years back. In doing that, I learned a LOT about coolant properties.

Glycol (antifreeze) is a terrible for cooling. It keeps in from freezing, sure, but it's really inefficient for actual cooling.

Getting rid of antifreeze will lower your temps, but you get corrosion problems (really bad). So what you need is something with corrosion inhibitors, but without the glycol. The solution is Water Wetter.

I love this stuff. And I don't buy into marketing hype, I've actually STUDIED it. I love this stuff. It has all the corrosion inhibitors, so I can run it without antifreeze. Just getting rid of the glycol will reduce temps usually be 5-10 degrees.


You won't get any protection from freezing, so you may need to switch back to antifreeze in the winter, but for summer it is great. It has allowed me to run my big 340 on the stock radiator without overheating. Just Water Wetter, and Distilled Water, mixed according to the directions on the bottle.

Honestly, it's probably worth a try.

[jon370r]

I mixed the Water Wetter with distilled water not anit-freeze. I need to check my ESR temp gage because even my 250pv cylinder would run up around 200 degrees and that had a nickle plated bore. With a dual pass oversize radiator that should have run 160-170 all day long.

[deathman53]

my motors run at 160-190 depending on the temperature. When its cold(~40 degrees), if it gets to 130 degrees, thats high. On the atc I have pwr radiators and trx has afram double pass radiator. Both have very similarly modified motors, with the only difference being the pipe.

[Huskydoggg]

Wilkin,
I hope you can point me in the right direction.
I have a 2007 Husqvarna WR250 that produces AC voltage. I want to add a cooling fan and found a suitable fan that draws 2.3 amps DC. Can the fan motor be modified to run on AC, or is a rectifier my only option? How do I "float" the stator ground?
Any help would be much appreciated. Thanks.
Steve

[wilkin250r]

Originally posted by Huskydoggg
Wilkin,
I hope you can point me in the right direction.
I have a 2007 Husqvarna WR250 that produces AC voltage. I want to add a cooling fan and found a suitable fan that draws 2.3 amps DC. Can the fan motor be modified to run on AC, or is a rectifier my only option? How do I "float" the stator ground?
Any help would be much appreciated. Thanks.
Steve

There are a few considerations to be made.

First off, 2.3 amps at roughly 12V is about 40 watts. You need to make sure that your electrical system is capable of supplying that additional 40W without strain or damage.

If you pass the first condition, the rest can be fairly simple.

The fan needs DC, there is no way around it, no modifications that can be done to change that. However, you won't necessarily need to convert your ENTIRE system to DC. You can (with my help) build a small inline circuit that simply converts the fan inputs to DC, but leaves the rest of your system AC.

Let me do some calculations, I'll get back to you.

[blasterandy]

didn't the oddessy have a rad fan... i would try and look into that.