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Re: Hold onto your air (well, air and oil) cooled boxers
Posted: Sun Aug 28, 2011 9:38 am
by Dr. Strangelove
mogu83 wrote:Anyname wrote:BMW has said they will not build a 600RR. . Besides, the 600 sport bike market is very slow these days.
I don't know about that, I'm seeing more and more Suzuki Wee Stroms showing up at the Beemer rallys. I can only assume it's ex or current Beemer owners riding in on them.
MSRP $8,099 Watch out BMW I know a few Beemer riders that are lusting for one of these.

over in the VStrom Forum there is a thread that is something like: Did you come from BMW to VStrom?
There were lots of entries, and many said yes, they had. Also, many "missed" the BMW, though not all. The takeaway message I got was the BMW, roadsters mostly, was a better bike in terms of power and fun to ride, and not worse in reliability. The grass may seem greener, but it ain't necessarily so.
They were both considered good bikes
John
Re: Hold onto your air (well, air and oil) cooled boxers
Posted: Fri Sep 02, 2011 4:13 pm
by deilenberger
firstforward wrote:Seriously now; all engine’s use the engine oil to cool various components to some degree, the engine’s life started out as primarily cooled by air flow over the engine, I think it is arguable with the fitment of an oil radiator what takes precedence as a description.
Just for curiosity - get an airhead side by side with your R1200R.
Compare the cooling fin size and placement. The fins are extensive on an airhead and MUCH much deeper then the R1200R ones - that's with engines with less displacement, less HP output, and running much richer (which leads to cooler engine temps.) The cylinder fins on a hexhead are almost non-existent, and the ones on the heads - not much different. The ones on the valve covers are obviously there for decoration. Plus - the entire engine is painted, which decreases the heat transfer from the aluminum to air.
Add in a complete separate oil cooling circuit, complete with a thermostat (so the engine CAN heat up enough to run cleanly - that's the only reason for it..) - and IMHO - you have an oil cooled engine with some vestigial air cooling.. or fins to make it "look like a motorcycle".. The fact that the special police models have cooling fans on the oil cooler - allowing them to idle for an indefinate period of time shows the oil cooling is capable of cooling the engine, without any air flowing over it at all.
I really don't care what BMW says - that's marketing talk... bet if you talked to a BMW engine engineer he'd explain in detail how the cooling system works.
Re: Hold onto your air (well, air and oil) cooled boxers
Posted: Sat Sep 24, 2011 12:10 am
by Acpantera
I've been thinking of this a lot lately, maybe the changing of the iconic air cooled boxer to liquid cooling is not the big news here. Noting that the intake and exhaust position this would indicate that BMW wants to have a dual cam set up with one cam for exhaust and one for intake valves. (currently both cams have one exhaust lobe and one intake lobe). This revised cam/valve arrangement would allow for variable valve timing or even BMW's valvetronic system that rids the intake track of throttle plates, decreasing pumping losses, increasing power and fuel economy. Maybe direct fuel injection is in the cards too.
Remember that excellent air flow over both cylinders is not the only benefit of the boxer engine. Low center of gravity, even firing and balance are all good engine qualities of a motorcycle engine. I hope they they pull out all the stops and bring the technology that is common place in their auto engines to the ole boxer..... let evolution happen.
Re: Hold onto your air (well, air and oil) cooled boxers
Posted: Mon Sep 26, 2011 3:49 pm
by Tr250Tom
"...even firing and balance are all good engine qualities of a motorcycle engine."
Yes, I agree with most of your post. I would point out though that the boxer configuration is in no way necessary for "even firing." A typical parallel twin has the same firing interval as our bikes (once every 360 degrees of crankshaft revolution.) The firing interval is a function of both cylinder location and crankshaft pin configuration.
And I also own a Ducati that makes a powerful argument AGAINST "even firing"...
Cheers, Tom
Re: Hold onto your air (well, air and oil) cooled boxers
Posted: Tue Sep 27, 2011 9:13 am
by deilenberger
Acpantera wrote:I hope they they pull out all the stops and bring the technology that is common place in their auto engines to the ole boxer..... let evolution happen.
Given the problems they've had with their recent auto engines (from exploding VANOS on S54 engines to failing high-pressure-fuel pumps on most of the turbo engines) that may not be something to hope for.. nice when they work, unfortunately, with increased complexity comes increased failures.
Re: Hold onto your air (well, air and oil) cooled boxers
Posted: Tue Sep 27, 2011 2:05 pm
by Acpantera
New technologies are seldom perfect but I will not be scared away because of some nay sayers. I remember all the grumblings when electronic fuel injection started coming on big, now carbs rarely seen on new motorcycles and extinct on autos . Think of all the advancements in the last 50years in the automotive world, many have failed flat on their faces only to become mainstream (remember Cadillacs 8-6-4, now "cylinder on demand" engines are used by many manufacturers) BMW has used valvtronic for over 10 years now, I would not call that a flop by any means. I'm pro evolution, and happy we have efi, abs, traction control, and radial tires etc... It would be BMWs M.O. to be first at bringing innovation to motorcycling, Thats what draws me to the brand.
Re: Hold onto your air (well, air and oil) cooled boxers
Posted: Tue Sep 27, 2011 2:41 pm
by tinytrains
deilenberger wrote:firstforward wrote:Seriously now; all engine’s use the engine oil to cool various components to some degree, the engine’s life started out as primarily cooled by air flow over the engine, I think it is arguable with the fitment of an oil radiator what takes precedence as a description.
Just for curiosity - get an airhead side by side with your R1200R.
Compare the cooling fin size and placement. The fins are extensive on an airhead and MUCH much deeper then the R1200R ones - that's with engines with less displacement, less HP output, and running much richer (which leads to cooler engine temps.) The cylinder fins on a hexhead are almost non-existent, and the ones on the heads - not much different. The ones on the valve covers are obviously there for decoration. Plus - the entire engine is painted, which decreases the heat transfer from the aluminum to air.
Add in a complete separate oil cooling circuit, complete with a thermostat (so the engine CAN heat up enough to run cleanly - that's the only reason for it..) - and IMHO - you have an oil cooled engine with some vestigial air cooling.. or fins to make it "look like a motorcycle".. The fact that the special police models have cooling fans on the oil cooler - allowing them to idle for an indefinate period of time shows the oil cooling is capable of cooling the engine, without any air flowing over it at all.
I really don't care what BMW says - that's marketing talk... bet if you talked to a BMW engine engineer he'd explain in detail how the cooling system works.
Further proof of the high percentage of cooling the oil cooling system provides, is BMWs instance that the air scoops on the front forks not be removed, as the directed airflow through the oil cooler is vital. See owners manual.
Scott