Cool Weather Ride . . .

[CTellman]

Yesterday, it was in the 40's here on the NC coast. I went for a 100 mile ride out to the ferry terminal that connects the mainland to the Outer Banks. It was two lane and 35 to 55 mph speed limit. When I returned home I felt to see if the oil cooler was warm. It was cold! Does this sound right?
Campbell Tellman II
'93 R100RT

 

[keelerb]

Sure does. Cooler has a thermostat so it only opens when oil temp gets to a level that makes additional cooling necessary/desirable. You didn't get there yesterday.

Doesn't surprise me at all. Means it's working.

 

[lkchris]

Absolutely.

For about the 100th time ... the oil cooler thermostat only opens when the engine is working hard. This doesn't happen until at least 70 mph--sustained for a significant period. The work the engine does is push the bike against aero resistance.

Good to remember that comparing air cooling and water cooling is like comparing apples and oranges. A water cooled engine could actually heat up at idle due to water pump turning more slowly plus less air through radiator. The aircooled engine will cool down because it's burning less fuel--plenty of radiation capability to make up for loss of airflow across fins. Unlike some instances with a water cooled engine, the last thing you want when stopped is any rpms at all above idle with an aircooled engine.

If you want to feel heat in your oilcooler, run for 80 mph for maybe five minutes, then immediatedly stop and get off and feel the cooler. The thermostat will have closed by then, but you'll still be able to feel the heat.

This is good design, as there's no value in overcooling the oil. The GS is a special case as it could certainly be ridden under very different conditions than a street bike. The GS configuration exists solely to account for those special circumstances. There's no value to eliminating the thermostat on a street bike, and it could actually be detrimental.

 

[skiteach]

To add to Ikchris, Oil is designed to lube it's best around 180- 220 deg. At least for watercooled engines.

 

[keelerb]

And by way of illustration, I took my Harley out today in low 40s weather (Beemer gets pressed into service when it goes lower) and never got the oil temp above 200. In warmer weather it usually goes to 220-230 on a similar ride. So ambient temperatures do matter.

 

[BMWRich58]

And by way of illustration, I took my Harley out today in low 40s weather (Beemer gets pressed into service when it goes lower) and never got the oil temp above 200. In warmer weather it usually goes to 220-230 on a similar ride. So ambient temperatures do matter.

In cooler weather,I block off the oil cooler. This allows the engine to attain it's operating temperature. Thus resulting in good gas mileage. (Keep an eye on the temperature bars/gauge) don't wanner overheat an damage the engine. I have a cover that is cut to allow certain amount of air flow to prevent overheating yet allow the engine to reach it's operating temperature. I also do this on my truck.