I sold my R65, now I'm in the market for a K100RS.
Did the K100RS models get the 100hp motor?  Or that's only on the European K100 models? 
I read somewhere that the European K100 had a different cam?  I know the K1100 motors have 100hp.

NOPE!

The most powerful version is "only" 90HP, but the torque largely compensate for the lack of HPs.
I don't know a lot of bikes where you can ride at 60kmh in 5 gears, open the throttle to full and get a kick in the butt because the engine is pulling like an ox.
I know a lot of riders who got the latest BMW models with a lot of HP, but all of them say that they miss the character of the K100.

K100RS16V have 100hp.

+1 with Inge on K100 16V.

There is a persistent story that the '83 - '85 K100 (8V), both US & Euro models, had different cam profiles which purportedly gave additional horsepower as compared to the later 8V. However, it is unsubstantiated.

Two Wheels Better wrote:+1 with Inge on K100 16V.

There is a persistent story that the '83 - '85 K100 (8V), both US & Euro models, had different cam profiles which purportedly gave additional horsepower as compared to the later 8V. However, it is unsubstantiated.

Well, I've not long since taken ownership of a 3700 mile 8v K100 Basic, Naked, call it what you will.



It's an absolute rocket ship! Smooth and quite powerful. Even with two of us on the bike it has so much torque and the goes again at 5000 rpm. It actually frightens me a little as the engine far out performs the chassis with it's soft forks and crap brakes. You could easily get into trouble aboard the Brick.....but I love it!
I've got a new R1200RS and this morning we went out for breakfast, I took the K100 again.

Two Wheels Better wrote:+1 with Inge on K100 16V.

There is a persistent story that the '83 - '85 K100 (8V), both US & Euro models, had different cam profiles which purportedly gave additional horsepower as compared to the later 8V. However, it is unsubstantiated.

I have seen quoted in Clymers (it may have been Haynes but unlikely) that the "Californian" models were equiped with inlet cams that opened the valve 10° ATDC as against the European models it was 10° BTDC.  This effectivly lowers the compression ratio because there is less charge to compress and that in turn lowers combustion chamber temperature which produces less of the evil oxides of nitrogen to poison the atmosphere.
Don't blame me if Clymers have it wrong.

That surely doesn't sound like hotter cams/more power!

I have a BMW Parts Snab book (pre-ETK) from the era at work and the part numbers even then were the same for all models. Perhaps it was a short-lived thing they did!?

I recall reading an article wherein the author pokes fun at the idea of creating a rumour around the hotter cams issue and said he made it up at the time, it stuck and he was surprised.

The overall performance would be little different between the two. The retarded opening of the inlet will lower the bottom end torque but will make more HP in the top end however that benefit would probably be negated by the small drop off in compression.  I would say that a drop of 3 to 5 HP would be the overall result but taking something like a 1/4 mile time and terminal speed the engine with the "Hotter Cams" would have a slight advantage and by slight I mean about 1/10 second if that

Here 'tis

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