This is the latest work of Tobias Guckel, a German top custom builder. The frame and the engine derive from the Kawasaki H1 and H2 respectively, probably the fastest production bikes of the 70Ęs. 
The frame has been modified to gain some strength, that was an issue also back in the 70s… The carburetors are Mikuni VM 34 and the custom exhausts are Jolly Moto. The forks, swingarm, wheels and brakes come from a Suzuki GSXR1100.