305 CDI voltage source

Were the green measurements done with the coils disconnected? If not, I would try with them disconnected.

With the ignition coils disconnected they reached 1.5 -2 V max. I might have seen it reach 10 V for a fraction of a second after trying for an extended period.

Since the CDI has recently been replaced and the coils have been tested as good I'm still thinking that the capacitor isn't getting fully charged. When I tested the coils down at the university I was able to determine that 12v supplied to the coil was enough to make it fire. It's my thinking that the capacitor must need to reach a charge of over 12 V in order to fire the coils. Since the exciter coils rarely supply more than 3V it's my thinking that is the problem. Hopefully I'm not getting myself wrapped around the axel here but it's the best theory I can come up with at the moment. Since the stator coil assembly is fairly rare for this model I think I'm stuck looking for a parts bike unless I want to fork over $300 for a new one. :pinch: I'm considering dissecting the spare CDI I have so I can see exactly what they are using for components. Not sure as they are also fairly rare and a little expensive.

The capacitor needs to have about 300v or higher on it. That's why I wanted to see the voltage at the coils, without the coils loading it down. 1 -2v is too low, even 10v would be too low, since there is really no load on it. When the coils are connected, the voltage spike is too brief for a meter to capture it. Without the coils loading it down, I would have expected to see a decent reading.

But that was all to see that the CDI module was at least responding to the trigger signals. With the charging coil messed up, I wouldn't expect the voltage on the capacitor to get very high. So hopefully it's just the charging coil(s) that are messed up (even though you'd have to replace all of the magneto coils).

If the other CDI module is a metal box with screws, you might be able to get it open without destruction. If it's just a bad capacitor, you could probably get a replacement easily.

OK so drastically lower than what it should be. even though it is only at an instance i should be seeing a much higher value if it is supposed to be 300V . I guess I'm just surprised it is that low of a discharge with that being the requirement. the CDI is a silicone rubber filled plastic box. unfortunately after years of vibration the rubber is more like cement. sounds like the consensus is the exciter coil. with two different CDI behavior being similar it really points that way.