Life of magneto & CDI

M

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So I was going to the store the other night, my bike was running fine and perfect. After coming out of the store I could not get my bike to start. It was dark and I really didn't feel like messing with it and it's only a 1.9 mile ride so I just pedal through it. My bike has been parked for 4 days now and I haven't even looked at it.
With my multimeter, would setting be on Ohms?.. what should the settings be to see if the Magneto is still working and how would I know if the CDI is still working without trying to pedal and grabbing the head of the spark plug wire and getting shocked.?
As I was trying to get it started it was making kind of like a screaming ping sound whinning everytime I release clutch. And I couldn't smell gas when I was pressing the button on the carburetor. It was dark and I'm not sure.
Although this engine has over 2,900 miles on it. It seems like I'm putting a new CDI or a new Magneto on it every 700 miles and I'm gone through 3 each. I still have the old ones so I need to test those as well but I'm pretty sure it's a carburetor issue
I put about 600 miles on both units and I'm wondering if it's possible that's where the problem is or maybe it's just a simple carburetor cleaning because I have noticed when I press the button on the carburetor fuel does not always come out.
I will work on it when I get home today from work and I know we have threads on the same topic but instead of trying to find the thread, could one of you nice folks help me? LOL
 
This may sound silly but i once had a similar problem with having to change my cdi and or magnet and armature (whole magneto unit?)
then come to find out after my kill switch finally stoped working, after i changed the kill button to a new one all my other electrical probs stopped being.
 
I actually have an extra kill switch came with new handle grips.... Idk... I'm not feeling any spark off plug wire head either... or maybe I'm just too used to the electrical current and it's not strong enough to feel it....?
It's not the kill switch, I just replace the kill switch with the new one that I had.

As I'm pedaling and trying to start it there is like a screeching sound there is compression but it's like a popping screeching sound like something rubbing against something.
Could this simply be the electrical system and have zero to do with any damage to the engine?
And I still like to know the range is I'll be looking for when I'm testing the Magneto and CDI
 
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I actually have an extra kill switch came with new handle grips.... Idk... I'm not feeling any spark off plug wire head either... or maybe I'm just too used to the electrical current and it's not strong enough to feel it....?
It's not the kill switch, I just replace the kill switch with the new one that I had.

As I'm pedaling and trying to start it there is like a screeching sound there is compression but it's like a popping screeching sound like something rubbing against something.
Could this simply be the electrical system and have zero to do with any damage to the engine?
And I still like to know the range is I'll be looking for when I'm testing the Magneto and CDI
1542745494022.png
The CDI should read "closed" if it's good & open if bad....if I'm wrong, someone on here will jump my s**t..(carry on)
 
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To
CDI?
Magneto?
The magneto. This check will verify that you have an intact coil winding. Info I have says it is 3,600 turns of 35 GA.
323 ohms.
The one on my bike measures 355 ohms.
If it's open, check solder connections. It could just be that the fine magnet wire is broken where it was soldered to the tabs and meets up with the blue or black wire.
If it reads substantially less than 300 ohms, it is probably shorted internally and would produce low voltage and probably no spark.
 
So if the Magneto is fine how do I check to make sure the CDI is okay as well?
Gonna work in in a few...
 
So if the Magneto is fine how do I check to make sure the CDI is okay as well?
Gonna work in in a few...

I don't know that yet. I would think you should be able to check the secondary coil by unscrewing the plug wire from the CDI and measuring resistance from the screw contact to the black ground wire. It should not be open, but rather a large resistance from the long, fine winding.(maybe 10K ohms?) If no one else answers, I'll check mine for you tomorrow and see what I get. I'm pretty sure the stock CDI comes with a resistor cap, probably 5K ohms, which is why I suggested unscrewing the wire from your CDI so you get the wire and cap out of the circuit.

I'd only be speculating about what behavior you are likely to see between Blue and Black. I'd speculate you should initially see it take some current as it charges up the capacitor, and then go open. I'll do some testing tomorrow if I get a chance.

I've been planning on doing some testing/experimenting with the magneto and CDI. Just been waiting on weather to be nicer and some parts to get here.
 
The cdi (stock) will read 6-8 ohms on the 2k setting of meter,you wont get any reading between the black wire and the screw for plug wire as it's not a complete curcuit the ohms reading will be with both wires blue and black.
 
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