Cooling fan for XS?

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After reading several threads on oil coolers, I was wondering if anyone has considered mounting a cooling fan to assist with cooling the heads on our XS650's? I have a Harley I built up with high compression and installed Love Jugs (https://love-jugs.com/shop/) cooling fans, and they did better at cooling the oil and heads than my fan assisted oil cooler. Maybe something like this mounted between the frame down tubes? Might not look all that great but with a little ingenuity you never know.. Thoughts?
https://www.amazon.com/Coolerguys-120mm-120X120X38-Airflow-Waterproof/dp/B07P46D62Q
 
Might be something to look at if you spend a lot of time in stop and go traffic.
 
XS John who passed away a few years back did a lot of research on getting these bikes to run cooler with much success. His solutions included everything from lower compression ratios to tiny fins that ducted more air to the heads. I've yet to lower compression but I did manage to build my own version of larger cooling fins that attached to my crash bars.

You're on the right track.

Here in North Carolina it gets hot. I constantly ponder how I might make my XS run cooler. I'm currently pondering adding a deeper sump, an oil cooler, and an extra oil pump to circulate oil between the sump and the cooler: http://www.xs650.com/threads/electric-oil-pump-advice.56625/

Still, that leaves the heads.

I saw a picture of a liquid cooled XS that someone in Australia had built: https://www.xs650.org.au/offbeat.html
 
Appreciate the feedback, all. I've read a lot from XS John (RIP) on the carbon cooling fins, etc., as well. Some amazing stuff. I won't be lowering compression just to achieve cooler running temps, either. Not worth giving up performance. If the head temp on our XS's is a significant cause for increased oil temps (which I gotta believe it is), having a consistent flow of air targeted at the heads, especially in stop and go driving per Jim's response, will in effect act as it's own oil cooler. That was precisely why Lovejugs developed the cooling fans for the Harley line that I wound up installing, and was quite amazed at the impact it had on lowering oil temp as well. I'll order one of those fans from Amazon in my original post since they are less than $20, get a thermal thermometer/cam, and experiment with it come summer.
 
... If the head temp on our XS's is a significant cause for increased oil temps (which I gotta believe it is), having a consistent flow of air targeted at the heads, especially in stop and go driving per Jim's response, will in effect act as it's own oil cooler...

After I installed a high-volume oil pump (to get more oil up top), I noticed that my sump oil temps went up around 5-10°F. Must be from oil-cooling the head...
 
One method of minimizing heat in the head is addressing the restriction in the exhaust port, by addressing the restrictions you increase velocity of the exiting exhaust pressures thus minimizing heat build up in the head. Also thermal barrier coating the valves, combustion chamber and the exhaust port will also aid in heat reduction.
 
One method of minimizing heat in the head is addressing the restriction in the exhaust port, by addressing the restrictions you increase velocity of the exiting exhaust pressures thus minimizing heat build up in the head. Also thermal barrier coating the valves, combustion chamber and the exhaust port will also aid in heat reduction.

Out of curiosity, does anyone know if running a good two-into-one exhaust will improve efficiencies of evacuating exhaust, and thus help lower the head temp while improving overall power slightly? The exhaust pulse of one cylinder helps to "pull" the exhaust from the other, etc. That is the case for well-tuned pipes on a Harley but I don't know if that would be the case on these 360 degree twins. I would think so, but if it is negligible then probably not worth the expense.
 
Out of curiosity, does anyone know if running a good two-into-one exhaust will improve efficiencies of evacuating exhaust, and thus help lower the head temp while improving overall power slightly? The exhaust pulse of one cylinder helps to "pull" the exhaust from the other, etc. That is the case for well-tuned pipes on a Harley but I don't know if that would be the case on these 360 degree twins. I would think so, but if it is negligible then probably not worth the expense.

I hope so as I recently put my old 2-1 back on. But it's so ugly.
 
Out of curiosity, does anyone know if running a good two-into-one exhaust will improve efficiencies of evacuating exhaust, and thus help lower the head temp while improving overall power slightly? The exhaust pulse of one cylinder helps to "pull" the exhaust from the other, etc. That is the case for well-tuned pipes on a Harley but I don't know if that would be the case on these 360 degree twins. I would think so, but if it is negligible then probably not worth the expense.
how a 2 into 1 pulls will depend on how well the primary pipes are plumed into the collector and how the collector is sized to engine displacement. Generally 2 into 1 power distribution is aimed at a certain RPM and power suffers in other ranges where as a good 2 into 2 with a cross over would delivery a wider power range for street use. Both systems have their pros and cons. If you're concerned about scavenging,you need to address the exhaust port protrusions,this is where you'll yield the biggest gains,then adapt a good exhaust system for further improvements in scavenging.
 
After reading several threads on oil coolers, I was wondering if anyone has considered mounting a cooling fan to assist with cooling the heads on our XS650's? I have a Harley I built up with high compression and installed Love Jugs (https://love-jugs.com/shop/) cooling fans, and they did better at cooling the oil and heads than my fan assisted oil cooler. Maybe something like this mounted between the frame down tubes? Might not look all that great but with a little ingenuity you never know.. Thoughts?
https://www.amazon.com/Coolerguys-120mm-120X120X38-Airflow-Waterproof/dp/B07P46D62Q
Lotsa good ideas already in response - a lot of us are sensitive to this topic. Probably no silver bullet but some combination of "22 shorts". Some years ago, looking at the engine front, I wondered why the horn hung as low as it did and fabbed a simple bracket to raise it, hopefully allowing more direct airflow to the cylinder head. Never took b4 and after temps, but it seemed to make sense at the time - at least it couldn't hurt. Make sure timing is spot-on and don't hang a tool bag above the front fender.
 

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Yeah, never could figure out why that horn was hung the way it is...no doubt blocking airflow. Was thinking it should be relocated but possibly use the horn bracket (modified as needed) to mount a cooling fan.
 
I'm not sure the electrical system is up to running a fan.
I have adapted a right side engine cover so the oil flows out one fitting and back in at another. I can add an external oil filter or an oil cooler or both.
After the cover mods I plumbed in a tee fitting so I could hook a car water temp gauge. Ran the oil out past the temp gauge probe and back to engine. Did a 60 mile loop on a sunny 75 * day to get oil temp and I shot head and cylinder temp with a laser temp gun. This was for a base line temps
Plumbed in an external oil filter hung of the front engine mount. Got about a 5* temp drop on all three places.
Added the oil cooler off a Yamaha 82 XJ650 Turbo. This is about the same size as the one Mike's XS sells.
This gave me about a 50* temp drop at all three places.
I don't recall exact temps but the oil was around 150*, I believe this is a bit too cool. From the research I've done oil temps should be around 185*. This warms the oil enough to evaporate moisture compression blow by which oftyen has unburned fuel in it.
These contaminates dilute the oil, cause sludge build up.
The 185* is low enough to prevent oil breakdown from excessive heat.
I have another oil cooler that is about 2/3rd's the size of the one I had try on the bike, just haven't gotten to it yet.
Since the testing I did I bought a dipstick with a temp gauge built in to monitor oil temps. Much better than my tee fitting and car temp gauge. I'm not sure if these are still available from Dog Bunny or not. I use the same one in all three of my XS650's, just sap it to the one I'm riding at the time.
I have the oil cooler hung as high up on the frame down tubes under the steering neck as I can get it. Some think that's not a good place for it. I think it works fine. The extra cooling of the oil more than makes up for any loss of air flow over/around the head.
Here's some pics. One shows the oil filter and oil cooler, the other how the cover is plumbed.
Leo
 

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Lotsa good ideas already in response - a lot of us are sensitive to this topic. Probably no silver bullet but some combination of "22 shorts". Some years ago, looking at the engine front, I wondered why the horn hung as low as it did and fabbed a simple bracket to raise it, hopefully allowing more direct airflow to the cylinder head. Never took b4 and after temps, but it seemed to make sense at the time - at least it couldn't hurt. Make sure timing is spot-on and don't hang a tool bag above the front fender.

The first thing to break on my XS was horn so I replaced it with a slightly bigger and louder horn I pulled from a junk car. And for airflow I moved it to the left side of the frame just below the gas tank.

My intention is to mount a pair of oil coolers on my crash bars where they will be out in the wind and plumb them into an extended sump via an electric oil pump with a low temperature switch to shut it off. I'm aware that the stock alternator won't power such a pump but I just shelled out for a Hugh's Hand Built 200 watt PMA and ignition system so I think I've got it covered.
 
Leo, to save having to connect in the other cooler to test what area of cooler is needed, you could mask off a section of the existing cooler and do a test.
 
I'm not sure the electrical system is up to running a fan.
The fan only draws like .75 amps, plus I'm running LED lights so shouldn't be an issue. That said, impressed with results you posted from oil cooler. By chance did you take before and after heat readings of the head after installing the oil cooler?
 
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