Interesting stuff Kat, for a test mule that R1 is well turned out and I tthink in volume production both appearance and packaging could be improved quite a bit. I remember that WR450 2-Trac too and think there were posts about at the time of launch. I think people like the edgy feel of a traditional sports bike and the 4wd seems like it dulls some of the feel from what is in the article. I can see it working a tourers and adventure bikes though. Imagine a KTM 990 fitted with it.
There have been other 2wd drives bikes, back in the 1960’s. Again I think there are posts on here about them, but they used chain drive I think and were exclusively off road machines