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Discussion Starter #1
I'm installing the RTP oil cooler cooling fan and want to use a thermostatic switch to control it. I've seen summit racings adjustable units with relay, temp probe, and wiring harness, but I would rather keep it simple and use a screw in or in line style. I need to figure out a good temperature range for on/off so I can purchase the correct switch. Anyone know? I tried various searches on the internet with no luck. Thanks in advance.
 

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Remembering that this an an oil cooler, not the radiator of a water-cooled vehicle or an air intercooler, here are some thoughts.

Oil operating temps up to mid 200s don't stretch the capability of modern oils at all. Reported IR temp readings for R1200a are in the 220ish range. You do not want to drop temps extremely low- it is not true that lower is better as some believe- keeping enough heat to minimize water vapor collection in the engine is one and sticking somewhere in the range the designers intended for a whole lot of things like fuel programming, etc is another.
The whole purpose of the fan is to prevent overheating in long term idling and owner experience shows it is rarely needed on R1200s not in police use because few encounter the necessary condition. Unless you have prior experience indicating you operate yours in ways that could overheat it, its probable you don't need it. (The longest I'm likely to ever be in 100 degree stop and go traffic is 30 min and mine does not get excessively hot in those condition though it gets hotter as noted by the gauge)

With that above in mind, I would start by installing a 200 degree fan thermostat and see what my operating temp gauge tells me when it is working. Running the fan a little earlier with a low temp thermostat may have less impact than you think for a variety of reasons but you can drop to a lower number if it doesn't do enough (unlikely). Or you could simply use a manual switch and run it when you need to in the event your bike runs colder than you like with the thermostat. I would stick to probes that fit in the fins or similar. They are proven reliable and easy to service if needed.

I use some of the low temp ones on intercoolers where cooler is better. Intercoolers on street cars are often a bit small for sustained boost use (they heat soak and lose abilty to drop enough temp off the compressed air charge) so need some help from fans in that case where as cool as possible is the goal, unlike oil where proper operating temp is the point.
 

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Discussion Starter #3
Thanks for the well thought out reply. The reason I wanted to install one is last summer when coming back from Canada, we were in 85-90 degree temps and traffic was backed up over a mile from the crossing. The oil temp started rising steadily over about 10-20 minutes activating the warning light. I then shut it off and pushed the bike all the way! Luckily it was flat but in full riding gear I was sweating and very uncomfortable. I vowed I would never do that again. Even if it never happens again, once was too many times. I'll probably do the adjustable unit with temp probe from Summit Racing. It comes complete with fuse and relay. Thanks again.
 

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Discussion Starter #5
I used that link to get the parts list needed to install the fan. He used a manual switch to turn the fan on/off and I am going to use thermostatic control.
 

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The temp on my 05 RT is in same bar on the guage just below center in summer at 110 deg or now winter at 65.
 

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Discussion Starter #7
Mine is too if I"m moving or only stopped for traffic lights. Try a 90 degree day in direct sunlight on blacktop sitting still for 20-30 minutes.
 

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Same slow progress coming back to the Seattle area on a Summer Sunday afternoon over I90 pass or up I5 from Portland. The northbound I5 freeway north of Seattle is famous for 3 hour stop and go events when there is an accident. Just no road work arounds that function with all the traffic. I too am going to install the fans. But I am going to just use a manual switch. A good reason to support lane splitting.
 
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