Ignition coil test

[kdxdazz]

Just checking the ignition coil on my 1997 kdx220. The primary windings measure 0.07 ohms and I'm not getting any readings in the secondary windings, my question is would the bike run like this, which it does or have I made mistake taking the readings, the bike has never run well but it has so many problems I can't tell

[Julien D]

I think your primary coil should be reading .16 - .24 at x1 Ohm. Secondary is like 5.0-7.6 W x 1k ohm.

I could certainly see how it wouldn't run very well at .07 ohm.

[bufftester]

To properly measure the primary disconnect the blue wire from the CDI box to the coil and measure between the connector on the coil the blue wire was attached to and the ground lug on the coil. As Julien noted it should be in the range of .16-.24 ohms. For the secondary you need to remove the plug boot and measure between the high tension lead where the boot was attached and the ground lug of the coil and it should be between 5k-7.6k ohms. Finally your plug cap resistance is measured by placing your leads on each end of the plug boot, should be between 3.7K and 6.2K ohms.
Wouldn't hurt to also check your magneto coil resistance (White/red wire to black wire 270-350 ohms).

[kdxdazz]

i checked the coil as per the service manual but i hadn't realized i have to remove the spark plug boot,i checked the magneto coil too but mine is the SR model and the magneto is very different,it doesn't have 2 coils its has the same style as a road bike with all the coils around the outside,from memory it was about 500 ohms,i just completed a full engine rebuild so at the moment it seems to be running better than ever but i have only gone to the end of the street,the secondary windings definately have no reading on the multimeter and i checked it everyway i could