Moleculo,
I was thinking over and over about how exactly our bikes could overheat, especially since the unique boxer design allows equal convection cooling, even at standstill. I decided to look at the microfiche and saw that there's an oil cooler pipe that runs the vertical length of the engine block as shown below:
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My hunch is that BMW isn't 100% confident in their small oil radiator design for such as massive 1.8L engine that they designed themselves a way to add additional oil coolers as either technical updates (TU's) or even possible class-action recalls?
Here's my logic, hear me out: Volkswagen had their air-cooled engines of similar displacement as ours for DECADES, but never did they passively cool their oil radiators. The radiators were always placed where the fan could cycle air, thus ensuring oil/engine temps would remain within spec.
Here comes BMW with a GORGEOUS 1.8l boxer engine, but decides to PASSIVELY cool the bike! This logic is great, so long as you keep the bike moving and air flowing over the radiator fins, but not so much if riding in stop and go traffic. I noted there isn't any oil jacket inside the cylinder portion, only channels which to flow oil to and from the heads. Additionally, without knowing true specs of the engine components (e.g. BTU capabilities of the radiator, PSI of oil flow, etc.,) I cannot say for certain whether or not this engine's existing radiator setup is sufficient. However, common-sense and knowledge of the world tells me that a large engine like this DEMANDS an active cooling system and/or a larger radiator and/or multiple radiators for extreme hot and/or extended stopped periods of running.
Moleculo, I think you just exposed one of the R18's achilles' heels....
Mike
