Pick-up coils

[81xsproject]

Could someone explain how they work to me so that I can use this info to figure out my MSD install

[TopCatGr58]

I did a search for pickup coils and RANDY since he's one of our main electronics gurus, and this is a response he made several years ago:

Pickups should read about 600 ohms. Measure from the connector at the ignition box and test the whole harness through to the pickup coil. Also check the permanent magnet in each pickup coil. A small screwdriver should be attracted to it fairly strongly. Do this WITHOUT the bike running.

The magnet is an important part of the pickup. If it's lost it's force, the pickup will test good but it won't generate a firing signal. As the reluctor passes the magnet, the reluctor transfers some of the magnetic force to the coil, inducing a signal. That signal is then amplified inside the ignition box to switch the coils.

Also, take note that ignition circuits 1&4 and 2&3 are discreet circuits from the pickups, through the box and into the coils , they don't 'join' inside the box, so it is possible and I've seen it, that one side of the box is faulty. This symptom is usually a cold solder joint inside the box.

HTH

Randy