12V Ignition Coil 21121-093 21121-1009 21121-1026 21121-1043 90mm

12V Ignition Coil 21121-093 21121-1009 21121-1026 21121-1043 90mm

Important Fitment and Mounting Information

• The original Kawasaki coils have 80mm mounting centres, while this replacement coil has 90mm mounting centres.
• A suitable adaptor plate or mounting modification is therefore required on certain models, including the Kawasaki Z250 Twin.
• An adaptor plate and mounting hardware are not included.

A simple, secure adaptor plate can normally be made from suitable material, such as:

• A short length of sturdy flat steel or aluminium
• A suitable section of steel angle
• A piece of Dexion style slotted angle racking

The adaptor must be strong enough to support the coil securely and withstand engine vibration. It should use the original mounting points wherever possible, with suitable fasteners, washers and locking nuts. Ensure that the coil, wiring and HT lead cannot contact the fuel tank, frame, engine or other moving or hot components.

This replacement provides a significantly more affordable solution than a genuine Kawasaki coil, once a suitable adaptor plate has been made.

Kawasaki Z250 Twin models use two separate single-output ignition coils, therefore two coils are required for a complete replacement.

This coil can be used for either the left or right ignition coil on the applicable Kawasaki twin-cylinder models.

Specifications

• Voltage: 12V DC
• HT outputs: 1
• HT lead length: 370mm
• Primary connections: 2 wires
• Mounting centres: 90mm
• Primary resistance: approximately 3.60Ω
• Secondary resistance: approximately 10.83kΩ
• Quantity supplied: 1 ignition coil

Please compare the mounting dimensions, wiring connections, HT lead length and available installation space with the original coil before ordering.

Replacement aftermarket part for the following OEM numbers:

• Kawasaki: 21121-093, 21121-1026, 21121-1043, 21121-1009
• and many more TBA

If your ignition coil has two primary wires and it is not obvious which way round these connect, please do not assume this automatically means the coil is faulty. On many coils the two primary connections are simply the two ends of the same winding, however some ignition systems are polarity sensitive, so it is always best to check against the wiring diagram or test results for your particular bike.

If you wish to test coil polarity, connect a voltmeter with the negative lead inside the spark plug cap or HT lead so it touches the metal or carbon inner, and the positive lead to a good earth point such as the engine block. Set the meter to a high voltage range and crank the engine over, there is no need to start it. A normal connection will usually show an upward movement of the needle or reading. If the reading swings the opposite way, reverse the two primary wires and test again.

Replacement ignition coils may give resistance readings that differ from genuine items or from figures shown in some manuals, and this will not always indicate a fault. When checking a coil, look for readings that are stable and repeatable. As a very general guide, primary resistance can range from approximately 0.6 to 5.0 ohms, with higher figures often found on older machines, and secondary resistance can range from approximately 6kΩ to 14kΩ, again depending on the application and whether caps are fitted. A coil is more likely to be faulty when readings are open circuit, short circuit, or vary significantly between repeated tests.