BMW chain drive conversion

One of the problems with racing a boxer BMW is the shaft drive, it jacks up and down with the throttle and gearing changes are hardly practical. This gentleman, Geunther Schwarz has a solution. Connect the final drive directly to the transmission, and run a chain and sprockets to the rear wheel. Shouldn't take too much designing, planning, fabricating and machining, should it? He said he saw pictures of a similar conversion in a German magazine back in the seventies, later found a copy of the magazine and from the pictures, built his own version.  Apparently the bike works well, the rest of the chassis is modified and braced, engine raised to get more (but not enough) clearance for the heads. Boggles the mind.