ignition system explained – Duane Ausherman BMW motorcycles Nov 08, 2019The two coil wiring diagram used on BMW motorcycles. One could wire up the coils in other ways, and the bike may run quite well. This is just showing the original wiring for optimum performance. Setting the points. Setting the points gap on BMW motorcycles is BMW Airhead Motorcycle Electrical Hints Beginning with the /6 airheads, BMW changed the wiring at the starter relay and changed the circuitry more than once. In all instances, certain things remained until the end of production, from the first /6 change. There are two wires leading from the battery + terminal into the airhead electrical system. R100RS clock - BMW MOA Jan 28, 2011The VDO replacement clock that I used couldn't have been an easier mount. Once you took the old one out the new one had a sleeve. You inserted the new clock in the same hole, you screwed this sleeve into the back of the gauge to snug it up in the hole.