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It runs! Nevermind. Oh, it runs again! Just kidding, nevermind...

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So my bike has been giving me some problems lately with the spark. After some simple DDMing I found that the resistance across the terminals of the ignition coil was between 0.5Ω and 0.6Ω, which is too high, so I replaced it, and it still wouldn't start. So I tested the spark plug cap, and it was bad, so I replaced it, and it started fine. Out of curiosity, I tested the new ignition coil, and the resistance across the terminals was the same as the old one.


Is the owners manual wrong with regards to the ignition coil?


Anyways, it ran fine for about a week, and then one morning while it had been in the shade, it wouldn't start, so I hopped in my truck and went to work. I came back in the afternoon (it had been in the sun), and, BOOM, it starts with no problems. Hadn't been touched since the morning. After that it ran for about another week, and then same thing. The exact same scenario played out once more until I decide to start investigating. 


I did the recommended tests in the owners manual, and got some confusing results. 


Resistances at the CDI plug:


Neutral switch - Good

Stand switch - Good

Ignition coil terminals W/key off - 0.6Ω (spec: 0.19Ω -0.23Ω)

Ignition coil terminals w/key on - Sometimes 0Ω - Sometimes 15Ω (Maybe a short?)

Pulse Generator W/key off - 463Ω (good)

Pulse Generator W/key on - 595Ω (no good)


Resistances at the unit:


Ignition coil to spark plug - Good (This was my previous problem)

Ignition coil terminals regardless of key - 0.3Ω - 0.6Ω

Pulse generator regardless of key - 463Ω (good)


The owners manual doesn't mention the key orientation for all of the tests, so I did it with both. I Imagine that the key being on or off shouldn't have an effect on the resistance of the ignition coil or the pulse generator, but I'm not sure about that. I added some pictures of the maintenance manual showing the tests I did. 


Does anyone have some insight into what may be the problem here?







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Oh, and it's an 03 650L

Edited by Riley16

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CDIs can pass all the factory specs and still be bad. L cdis are notorious for bad solder joints inside.

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Well, I gave the CDI a smack, and it started. I guess a bad solder in there could swell in the heat and make a connection, and then lose it again when it's cold. 


So, it seems like the CDI is bad, but do any of you have any knowledge about the differences in the ignition coil and pulse generator readings with the key on and off. That still has me a little confused. 



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