Why is my CDI not working on my bike?

Why is my CDI not working on my bike?

The problem may get worse as the bike warms up. It might not even hold low revs at all. You’ve tested everything but the CDI unit, including the charge of your battery, your spark plugs, the health of your coils, and the triggering mechanism itself. Could it be your black box?

What’s the difference between CDI and TCI ignitions?

For the purposes of this article, I’ll refer to all the black box ignitions as CDI, since they all use the same basic components: box, coils, sensor. This is a TCI box. On an electrical engineering level, it’s different from CDI, but the troubleshooting process is the same.

What is inside a CDI discharge ignition box?

What Is Inside a CDI Box? A typical Capacitor Discharge Ignition box consists of a small transformer, a triggering circuit, a charging circuit, and the main capacitor. The rectifier found inside the charging circuit stops capacitor-discharge before the moment of ignition.

What does the trigger on a CDI box do?

The trigger tells the box to fire, the box determines when to fire which coil with the capacitors, and zap goes the spark plug, ad infinitum. In addition to dischargin’ those capacitors, the box may also influence your rev limit, timing advance, and other variables related to spark, but that’s it.

How does an open ignition kill a spark?

With open ignitions a live wire goes from the ignition system to all of the switches. The switches are normally open, or not making connection, until in the “OFF” position. When in the “OFF” position the switch will ground the ignition wire to the chassis effectively killing the spark.

What causes a no spark condition open loop?

If after unplugging the 4-plug connector there is no spark or the spark still looks weak, this tells you that the problem is in the major ignition components like the stator, coils, cdi, spark plugs, spark plug wires, possibly a short in the wiring harness, a bad trigger coil or on EFI models your Injector Coils are bad (they measure 19-20ohms).

Where does the spark come from on a GY6 150cc?

There should be at least 0.05vAC coming from the trigger wire (Blue/Yellow). Write the voltages down and continue to the next step. The CDI Unit is powered by the AC current coming from the wrapped stator winding.

What to do if there is no spark in the ignition coil?

Just like before: while cranking the engine, use a multimeter to check for voltage at the two primary wires of the ignition coil. Connect your back multimeter lead to the black ground wire at the coil, and with the red lead to the lighter color wire (usually blue or purple, but it varies).

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