Just found this a few weeks ago, the only place I could find it for sale that would ship to US, is amazon.de.
I really fun with the build and of course my dream bike. I still remembering seeing the Orange R90s at a Dealership in Germany in 1975. I still lust after it now as I did on that day.

The manufacturer is Franzis.de, more info at https://www.franzis.de/auto-motor/bm...rmotor-bausatz

Bob M.

'04 R1150RT
'01 K1200LTC
'00 R1100RT
'99 R1100GS