I'm going to be something of a dissenting voice here. I will agree that there are thermal issues with air cooled engines, particularly when at low speed or stationary but some of the oil temperatures being bandied about here are way too low to drive off the combustion contaminants, in particular the water. Running a synthetic oil at 230 to 240F isn't so much a problem as a necessity to keep it in good condition. Running at 180F might be a good thing if you're racing and changing the oil after every meeting but on the road I wouldn't want to try for the 3000 mile change interval.
Additionally, the amount of cooling that the oil contributes versus air flow is questionable for the cylinders and heads; there's no cooling galleries around the cylinders, just fins on the outside remember. The MMC cooling fan seems to do a pretty good cooling job when it runs as programmed and, as has been pointed out before, the cowling that it fits in is very good at channelling the air flow when moving at speed around the cylinders giving more even cooling which is arguably closer to the original design assumptions for a bike engine.
Don't worry, nobody has to believe or even agree with me, and I don't even have the cooling fan on my M3W never mind an oil cooler and I live in a cooler climate than many on here. I have driven it hard in 95F conditions and it didn't seem in the least bit troubled unlike myself, I was a nasty sticky, dehydrated mess by the end of the day.
