Some info from a dutch website.
The BSA 650 engine is a reincarnation of the Rotax developed engine that was used first in the 1992 Aprilia Pegaso 650 (single cam, 5 valves), later in the BMW F650 (double cam, 4 valves).
The F650 RR models used by BMW in Dakar rallies late nineties were boosted from 652 to 675 cc, claiming 75 hp.
The new Gold Star was designed by UK company Redline Studios.
Ricardo developed the chassis.
The engine, same 652 cc, is under license from Rotax, in a redevelopment done jointly with University of Graz, Austria.
Cylinder head was reworked to improve emission figures , inlet tract tilted more horizontal.
