The PickUp is responsible for the correct ignition timing, similar to a Hall sensor in a car. It gives the CDI the signal when to trigger the ignition signal. Inside the PickUp is a coil with very fine copper wire windings. This induces a voltage during the rotation of the magic pole wheel. As soon as the area of the so-called break-off in the pole wheel is reached (two slim overlapping metal tongues in the magnetic core of the pole wheel), a voltage peak is triggered which triggers the CDI and releases the ignition signal.

If the pick-up is defective, the ignition signal is not triggered at all or is triggered at the wrong time.
A simple test can be carried out with a resistance measurement. To do this, measure the outgoing cable of the pickup against ground for resistance. The measured values should be 100 Ohm plus/minus 5 Ohm. Even with a higher resistance the engine is usually still running, but the higher resistance can already indicate a beginning defect of the PickUp.

The BGM PickUp is very high quality and always provides the CDI with an exact ignition signal through a carbon barrier layer. This improves not only the starting behaviour, but also with very high revving engines the ignition remains stable.