KZ650 Engine start troubleshooting

F64 wrote:

I can't remember if points are supposed to spark. 
It may be a sign of a bad points condensor.

A small amount is ok but the purpose of the condensor is to reduce arcing so if it's much then it's probably bad !

Wookie58 wrote:

F64 wrote:

I can't remember if points are supposed to spark. 
It may be a sign of a bad points condensor.

A small amount is ok but the purpose of the condensor is to reduce arcing so if it's much then it's probably bad !

Okay, so when doing the test tonight, I'll also clean the point with a file and thinner. That can't hurt. And if I still see consistent sparks at the points, i may have to change the condensers.

See what test results you get before you change anything (400 grit emery paper is best for cleaning the points)

Okay, so I cleaned the points a little bit with 400 grit emery paper and did the tests.

• When connecting the red lead of the voltmeter to the battery positive, and the black lead to the power supply of the coils (red/yellow), with ignition and kill switch on, i get around 2.7V. Not 0.5V!!
• When moving black lead to the black (and then green) wire of the coil, I get again 2.7V with the points closed, and battery voltage (12V) when i pry the point open. Same for both side.

I must admit that I have not clue what that means...

Rideallyear wrote:

Okay, so I cleaned the points a little bit with 400 grit emery paper and did the tests.

• When connecting the red lead of the voltmeter to the battery positive, and the black lead to the power supply of the coils (red/yellow), with ignition and kill switch on, i get around 2.7V. Not 0.5V!! OK, what this is telling you is there is a difference of 2.7v between the battery and the coils (max should be 0.5v) this is caused by a significant resistance between the fuse box and the coils (most likely suspects are ignition switch or kill switch) You can use the process in my fault finding guide for "resistance faults" to pin point the issue (should only take 3 or 4 pokes with a voltmeter to identify) - to eliminate everything else you could run a jumper wire with a 10amp fuse in it from the battery positive to the coil feed wires and see if she starts (just as a test)
• When moving black lead to the black (and then green) wire of the coil, I get again 2.7V with the points closed, and battery voltage (12V) when i pry the point open. Same for both side. This makes absolutely no sense - when the points are "open" I would expect to see the same voltage on both sides of the coil (2.7v)  as the circuit is broken - when the points are "closed" the black/green wires are grounded through the points (the points breaking the ground is what causes the coil to spark) so with the red meter lead on the positive battery post I would expect the black meter lead to see ground and read battery voltage !!!!!!

I must admit that I have not clue what that means... No worries

Thanks much. I'll go find the culprit for the resistance fault. I tested many time because I thought i did it wrong, but it always came back to 2.7V. I restored the controls on the handlebar recently, so maybe I somehow induced more resistance somewhere.

For the second test, i'm the dummy! I crossed MY wires walking back from the workshop to the computer. It should have read:

• When moving black lead to the black (and then reen) wire of the coil, I get the battery voltage (12V) with the points closed, and again 2.7V when i pry the point open. Same for both side.

But here is the good new. Somehow, after cleaning the points and playing with the wire connectors of the coil, I somehow started to get a sparks on cylinder #1 and #4 (and thus most likely the other ones). It took a few tries and some starting fluid, but she started!

So i'll try tomorrow again, chase the resistance fault and move onto the next issue: running rich.

I did think that might be the case