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1982 R100RT Oil Cooler Delete?

Snowbum has a reasonable discussion from his viewpoint on the oil cooler and why it was used on some models:

https://bmwmotorcycletech.info/coolers.htm

Sounds like the issue is that with the higher engine sizes and especially the use of fairings, the temperature goes up inside the engine. And it looks like it's not necessarily around town riding...unless the ambient temperature is quite hot...but rather high speed running as the heat output by the engine goes up in a non-linear fashion. He indicates that even a modest reduction in oil temperature can have a good effect on the oil used in the engine.
 
Thanks for the link, Kurt. This thread had had me thinking about Airhead cooling again, even though I haven't had one for many years. :)
 
Operating Engine Temps

I recently installed a dip stick with thermometer in the RT. Due to snow and ice, today was the first opportunity to try it out. With mid-40s ambient temps, and cruising around 5000 RPM on the interstate, oil temp was 200-220. When the sun was out, it was closer to 220, but when I pulled into the garage after dark, it was 200. I doubt the oil cooler thermostat opened today, but it will be fun monitoring temps when it begins to open regularly later, once hot weather finally gets here. I expect temps to increase commensurate with warmer weather, and probably top out around 275, but we shall see. Looking forward to warmer weather, with or without the new thermometer/toy to play with.

Before installation, I cross checked the dipstick thermometer with two other thermometers on hand, and all three were within 5 degrees of each other. So no regrets in the purchase.
 
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I recently installed a dip stick with thermometer in the RT. Due to snow and ice, today was the first opportunity to try it out. With mid-40s ambient temps, and cruising around 5000 RPM on the interstate, oil temp was 200-220. When the sun was out, it was closer to 220, but when I pulled into the garage after dark, it was 220. I doubt the oil cooler thermostat opened today, but it will be fun monitoring temps when it begins to open regularly later, when hot weather finally gets here. I expect temps to increase commensurate with warmer weather, and probably top out around 275, but we shall see. Looking forward to warmer weather, with or without the new thermometer/toy to play with.

Before installation, I cross checked the dipstick thermometer with two other thermometers on hand, and all three were within 5 degrees of each other. So no regrets in the purchase.

The big issue with Airheads in these temperatures is the oil barely (if it even does) gets hot enough to boil off moisture in the oil.
 
oil coolers

The big issue with Airheads in these temperatures is the oil barely (if it even does) gets hot enough to boil off moisture in the oil.

My limited experience: I have ridden 2 R100s with oil coolers; one was a fully faired RT. I rode both to Florida and back in the summer, 2 up, full luggage, highways over 70 mph in 90 degree weather some of the time. Not once did the oil cooler kick in.
 
My limited experience: I have ridden 2 R100s with oil coolers; one was a fully faired RT. I rode both to Florida and back in the summer, 2 up, full luggage, highways over 70 mph in 90 degree weather some of the time. Not once did the oil cooler kick in.

Well, riding to Florida in the summer is not the same as riding in 40 degrees in February which was the situation where moisture in the oil may not boil away. Where did you ride to Florida from?

However, I am curious. When riding along how do you tell whether the thermostat for the cooler has opened or not?
 
Well, riding to Florida in the summer is not the same as riding in 40 degrees in February which was the situation where moisture in the oil may not boil away. Where did you ride to Florida from?

However, I am curious. When riding along how do you tell whether the thermostat for the cooler has opened or not?

From New York.

Stop for gas, touch the oil cooler rad, definitely not hot to the touch.
 
Engine Oil Temp

I rode about 200 miles today, with ambient temps mostly low to mid 60s. The engine temp was around 230-240, while humming long at around 5000 on the interstate. So it seems the engine temp rises roughly 1 for 1 with ambient temp. Not sure at what temp the oil cooler stat opens, but looks like we'll see sometime this summer. As for how to determine whether the stat is open, pretty sure the radiator will become hot to the touch.
 
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