BMW Flat Twin


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Picture is from the ad of those days.
I don't think it has a nice kind of riding feel.
It's engine sits low, that makes the moving axle to lean very low too. But its seat is high, BMW says that's good for long distance comfort, namely, small bend angle of riders' knee. Bike's moving center is low, versus human mount position is high, they are so separated. That may make you feel some inconsistency.
Acceleration traction manner is not good. When you open the right side grip, rear shaft drive moves suspension first, then the tire begins to push the bike forward. That's vexatious lag. Moreover, low gravity center makes load transfer between the tires quite small, so it denies almost of your will to control the tire load. That's notable especially for RS type, because the heavy cowling sits on the front tire.
Its frame is a bit too flexible. Feeble frame connects highly mounted human and low running bike. BMW cruises good high speed, so it may discompose the rider.
It's a nice bike If all you want is to sit behind the big cowling and waits the bike arrives the object land. Engine runs impassively to high rpm, and that doesn't overawe rider at all. Easy maintenance, tolerant for bad weather, so good as a travel cage.
But if you have any passion to ride it actively, it will be denied by the bike.
Sure, it's just a anemic tool, not a precious partner.

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In 1980's.
Ancient glory of BMW has become a bit dull, and much of Japanese bikes have overlaid them on the road, and in the trade too.
Oh, is that going to vanish ?
No.
An unexpected angel has come.
The GS.

Picture is from the ad of those days.

It already passed long time for development, including Paris Dakar rally and so on. But  it has matured as a good bike at the end of the 1980's.
Big diameter tire and long suspension brings the body up, gravity center raises. Rear suspension link system improves traction response and now it's controllable. All these points vitalized the bike.
It's so big, but you can ride it very easily and fun.
High eye point gives you a fine view, and much cargo can be mounted, and more, rough road is welcome. If it's a model with a big cowling, that helps high speed cruising comfort.
You don't have to lump towards any situation.
That's the true king of tourer bike.
It has appealed world bikers, and resulted good sales, I suppose.
At that time, I saw many GS running cheerfully also here in Japan.

Well, but at the same time, an evil has come with the angel.
That has hit quality.
GS has diminished its durability compared to the former models of BMW.
"We hope your next bike would be also a BMW."
I don't know it's because BMW's "go update" campaign like above. But it can be said that it show a shift of BMW's strategy from "long-term happy" to "glad to buy a new one", and it brings some degradation of durability. Japs are catching up from the behind, and at this time, BMW has lost its absolute advantage of durability over the Japanese bikes.

Now these days, here in Japan, I can't see any GS of this era, besides many veteran RS are still running cheerfully. Only very few second-hand GS can be seen, but almost all of them are already burned out. GS might be a tool not a treasure for owners, I suppose, so they might use it like a pity workhorse. But GS with little running distance are also a jerky. Well, how can that occur ?
"BMW is durable and spartan." I think that's already a folklore.

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Later, BMW has refined flat twin engine, with new features like light crankshaft, injection system, etc.
Example photo of model bike.
That's quite new, not only engine, but frames, suspensions, all.
Fat radial tire makes its bank angle far deeper. But with flat twin cylinder arrangement, engine mount is needed to be higher. That results high gravity center, and big pitch movement.
BMW must be gentle, i.e., it hates pitching. So BMW did make a new type of front suspension to dam pitch.
Yes, it's quite new, including chassis dynamics.
Its father, former OHV flats, was inherent gentle bike. It could be ridden so easy, a bit anemic though.
OK, the son, OHC flats are also gentle, but it's nominal. That's the result of advanced peripheral technologies which covers its truth, I'd say. It's far faster than pa, but it also reflects some redolence of uptight feeling under its relaxed face. Maybe it's same for owner.
"Do you really understand what was your father's grace ?"
Its my question to the descendants.

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Well, below is a story of one sunday morning. I've talked with a elderly rider of R100RS at a highway parking area.
His bike was in very beautiful condition. But he seemed not to want to talk about the bike itself, but he talks well about a view from mountain pass, condition of road or climate, good season for riding, etc.
I suppose, his object was "motorcycling", not "a bike".
He might select his RS as a tool for bike touring, rather than a sport riding or a bike's premium. He knew what he want, including his age, it's calm feeling, not exiting.
He really likes motorbike riding, and enjoying it much.
After a short good luck, he's started to the highway. I saw his back, and it seemed to be very relaxing. It's a proof of his trust and confident to the bike.
OK grandpa, you've convinced me. Your selection is perfect.
Sure, your tough bike would bring you to anywhere you want, far and far, and beyond, forever.
It's the truth of the grace of OHV flats. He taught me that.

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New BMW flat is a technologically advanced bike, sure, it's truth. But its riding feel is quite distinct from its ancestor. Now I see many people selects new flats, and changes them frequently. And besides, many people still prefers old flats, and they will continue to hug it.
It's a detach between technology and merit, isn't it ?
I don't think it's a good attitude.
Then, what was wrong ?
How do you think about that ?

Ombra.
Dec. 2005

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