Ignition coil - high quality, made in Germany ►see details
BMW part number: 12138004104/B
Uses M4 clamping screws
Red plug connects to ignition switch board nr. 2 wire.
Cannot be used in combination with Pentacomm plate:
the 2 terminals point down in such a way that the spark jumps from the terminal to the Pentacom base plate
The resistance across the two spark plug leads on the ignition coil is +- 11 K Ohm, which is equal to the original coils
A weak spark at the spark plug can have different causes: a broken or poor quality ignition coil is one of them.
When the insulation (schellac) within the coil is damaged, the internal windings will short circuit causing a drop in voltage output.
Difficulties with starting when the engine is hot, is an indication of this.
But also a weaker magnetic field of the rotor will lead to a lower voltage output.
The magnetic field of a rotor can be strengthened by a specialized company.
It's recommended to use spark plug caps with 0 Ohm resistance
Shown in 2 exploded views
Motorcycle Model
Motorcycle Model
Main Group
Main Group
12 Engine electr. system

