Interesting to see how the water cooling is designed. It appears that only a very small portion of the cylinders contain water cooling passages, and there are no passages in the heads. Seems like this would make the system light and compact. The overall look of the engine is not too different than the oil cooled.
Is this a new concept for motorcycle engine cooling? Do other manufacturers use similar methods on their water cooled bikes, or is it more common to have a more extensive water jacket?
Yes, it is quite common to have water jackets which only extend as far down as the piston stroke, i.e., the region of the cylinder which sees high temp combustion gasses.
Ah yes. On further inspection I see the small web of passages around the valve seats.
The "concept" has much to do with engine "quieting."
'12 R1200RT, '02 R1100S, '84 R80G/S
This is a great thread, the photos, comments, access to the press kit. One thing I don't see much on is the E-Gas. I noticed they're talking up how well it will handle E-10. I wonder if they're really saying that they've built a lean-burn engine that won't surge ...
E-Gas is the BMW term for their electronic throttle control. It's not related to ethanol compatibility. The R1200 series does not surge, I don't know if it would be considered "lean" burn.
Here's what I read in the BMW ON magazine,
"The bike is designed to run on E10 fuel perfectly, but any alcohol content above 10 percent has not been tested."
I found it odd that at this late date, decades after oxygenated fuel was introduced, that someone would be touting this.
Maybe they include it to refute the less than honest dealer that blame everything that's wrong with your bike on ethonal.
Had one new wethead on display. Looked nice. No brochures, but I was there at opening time on Friday. The BMW rep was nice and fun to chat with but did not have any info about the bike - I think I knew more about it than he did which is not a slam against him at all. After all, I read ON!
Felt a notch easier to toss a leg over for the vertically challenged AND those - like me - short on the inseam side....30".
No price was available. None of the guys from the local dealerships were in the BMW display area when I was there. Not all the models were displayed.
Vendor participation down quite a bit and heavily biased - as usual - towards the cruiser/do rag/dress like Village people direction. Sigh.
The new Cycle World [Jan-2013] has a 4 page article about the water cooled Boxer engine.
Marin County, CA
Some bikes. Some with motors, some without.