Oil Cooler Placement
 

I bought an 8-row oil cooler that head been installed on a racing VTR (I presumed), in Japan. I installed it in roughly the same position it had been installed on the race bike, judging by the length of the hoses, and according to my perusal of pictures of certain VTR1000F bikes online. I used my own, personal, God given sense of physics (who needs Cambridge, MIT, Planck, Newton, Einstein, Hawking, et. al.?), and the subjective measure of waving my hand around the header roughly in the planned installation position as the bike idled, judging the heat, to select the installation location. All these things being fair, a fresh wind in my face as I drove hard to leeward, I installed the cooler...

My initial, subjective impression was the bike ran about 15 to 20 degrees F cooler than it did with the stock cooler while at speed. This was based on my recollection of operational temperature before the swap, temp measured via the bike's temp gauge. I didn't write anything down, before or after the swap. (Who has time to document such things?) I was winging it, as every good adventurer will.

My thought is to get some 'numbers' from other of you other members (and I mean 'members' in the most congenial way) to corroborate--or refute--my subjective impressions of the cooler's performance.

To kick it off, here's today's finding:

Ambient Temp: 85F, maybe a 5-10 knot headwind:
Condition 1: Running steady (after 6 miles) at 70-75 MPH; Temp (as indicated on bike's temp gauge): 199-201F
Condition 2: Stopped at light (~3-4 minutes): 220F (and rising)
Condition 3: Running 40 MPH and 1 minute after condition '2': 205F

Summary: When I stop, the temperature goes up pretty quickly. As I move again, it falls pretty quickly. In general, this is analogous to the behavior I saw with the stock cooler.

Please share similar data points if you would so that I can get a feel for how good this thing's working. If you would, please share additional pertinent data, e.g., what cooler you're using: stock, modified (if so, how), etc.

Thanks,
Alan

One thing to keep in mind with all of this is that you do also gain an advantage by mounting the cooler low.
Yes the cooler behind the header is not the ideal location. Mounting it there does have obvious issues but most tend to forget that you are also moving the cooler out of the airflow that is going to the airbox.
So you not only get cooler oil but also cooler air charge.

Carry On.

Those numbers sound very high compared to what I usually see. Steady 70mph should drop it much lower and sitting at a light the fan should intercede well sooner than that.

Have you flushed the cooling system? Is the thermostat 1. In place & 2. Working properly? This bike will run hotter with no thermo than with one.
Also is you cooling system filled with no air pockets and properly bled?
Does your fan come on at I think 206ish?
Lastly, when I removed my stock rads they were really dirty and inefficient. You should ideally remove them to clean them but if not you can buy foaming air conditioner core cleaner at depot. It will at least help the heat exchange properties of the rads.

On the highway at even hotter temps than you state I would not expect sustained 200+ temps on my bike. Plus you said your old temps were a shocking 15-20* higher? That would put stoplight temps above shutdown levels so yeah IMHO something is amiss on your cooling system.

Last note. I am running the Chinese "racing" radiators which are 1.5" thick and the bike runs cooler for that reason also but your #s still seem very high.

I know this is tmi but I ran an 8 row in the stock location and the bike ran substantially hotter due to it blocking airflow to the rads.
Just wanted to retell that great old story. I was duly angry when I went back to stock and it ran cooler since I went to the trouble of building custom oil lines.

Thanks for your insights, smokinjoe.The 10-15 F cooler temp is with respect to the 'at-speed' condition. At-rest, after several minutes the temps are comparable to those with the stock cooler on my bike. The temp comparison between moving and at-rest is not linear. This makes sense...with nothing but the fan (when it becomes active, on my bike at about 219F as far as I can determine) to move air by the cooler veins when the bike's not moving.

If you could provide temp readings at similar parameters as I posted, that would help me evaluate. Since you are running 'improved' radiators, the comparison is not 'apples to apples'. But it would still be useful to have the numbers.

Alan

if engine temps is a concern, fit one of these: https://www.ebay.com/itm/Modquad-Radiator-Coolant-Inline-Cooler-Red-Polaris-RZR800-RZR900-RZR-800-900/200783264417?epid=209918346&hash=item2ebf9d7aa1:m: mepUSOY5YjnLAbOGez2vjPA&vxp=mtr

Been running one (not this particular unit, but one like it, which I also had treated with heat dispersant to make it yet more efficient/effective) for years now (in lower rad hose) and it works great...