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Discussion Starter · #1 ·
Okay, so let's get right into it. I've posted before about this issue, but it was quite long ago, and I have actually done the work now to test things.

First off, the main issue.

I'm getting no spark to my left cylinder at all, and the spark on the right cylinder seems quite weak. This is what originally brought the bike to a garage decoration. I swapped out the coils, and the same thing, so the issue was not the coil. I then replaced my CDI with one I bought from someone on craigslist. Swapped them out, and tried. The issue persisted. I then set to testing them. My multimeter doesn't have the x100ohms setting, nor the xkohms setting that the FSM says to use, so I set it to the lowest setting of 200ohms, and tried testing the CDI and got quite literally no reading from anything at all, so I'm not certain as to whether or not the new (still off of an old bike that was being parted out) CDI, or the original CDI are functioning properly. That being said, I went through the steps to test the stator provided on motofaction.org/motorcycles/honda-cx-gl/stator-test/ and it came back with this, picture in first response.

So, I tested all the connections it told me to, and they all said "correct" after I submitted the numbers, but it still told me "some of the coils on your stator are faulty". So, assuming they're not just telling me this so that I'll buy their CDI replacement, and I really do have a faulty stator, I either need to replace, or fix my stator if I can. This leads me to the issue of leaking gaskets as the engine has nearly 60k miles on it according to the odometer that hasn't worked since I got the bike, because the speedometer hasn't worked. I've put probably about 500-1000 miles on it. pretty sure it reads 54k or 57k. Don't remember off the top of my head. So, if I'm taking the engine off, I intend to replace the gaskets so it stops leaking everywhere.

Finally, I suppose I need advise on the spark issue, would like some input on the idea of a "full" rebuild. Still need to test compression, but the bike was running before I lost spark, and it ran quite well even, so I don't think I likely have many internal issues (worn piston rings, chipped or broken valves) besides the stator. I could out run my buddy on his CB750 who's speedometer topped out at 135. Lastly, as far as the stator goes, should I replace the stator, and hope for the best, or should I bite the bullet, and get the ignitech CDI replacement that's going to cost me about $100 cuz the only two online are in Germany? Are there other options, or ideas?

Any and all input so long as constructive would be cool. Thanks,

Micah
 

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I'd advise not tearing anything apart until you have actually diagnosed the problem. Can you post your actual resistance readings from the stator test. Some functional stators do test outside the range used in the motofaction test. Someone more familiar with the CDI ignition than am I can help knowing the numbers.
 

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Discussion Starter · #4 ·
I will take the measurements again tomorrow, and post them. It annoyed me quite a bit that it simply erased them and replaced the with "correct".
 

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Post your numbers and we'll have a look. The test needs to be done on 2K ohms as if done on 200 ohms the numbers above 200 will be incorrect but I'm assuming your meter is maybe auto ranging as some of the numbers that say correct are above 200 and the fail {5/8} is generally below 100.
 

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Discussion Starter · #6 ·
Post your numbers and we'll have a look. The test needs to be done on 2K ohms as if done on 200 ohms the numbers above 200 will be incorrect but I'm assuming your meter is maybe auto ranging as some of the numbers that say correct are above 200 and the fail {5/8} is generally below 100.

If I remember correctly it was on 2k as it had pretty clear instructions to set them there. I had two readings below 100, one at 198 and the rest were between 200 and 350. I believe 8/9 and 5/9 were both at 94. But I will measure again tomorrow, and post my numbers. I ordered a new rectifier/regulator because I can't imagine why on earth the stator would cause a no spark on left cylinder/weak spark on right cylinder issue. The regulator should distribute what it is getting evenly, so the bike should at least start I'd imagine. Either way, it was only 25 dollars, so by this next weekend I'll know if that was also the issue, part of it, or none of it.

While we're here, if no one minds, I also have a 77 XS750 with no spark at all, it's either got to be the condensers or the pick-ups right? Or could that also be a stator issue? I have the FSM for it as well, and will be running tests on it tomorrow as well.
 

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The issue with CDI is that it is independent of the 12 volt system and is self generating from coils 8 and 9 on the test..

Think high tech flywheel magneto.
 

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Discussion Starter · #8 ·
The issue with CDI is that it is independent of the 12 volt system and is self generating from coils 8 and 9 on the test..

Think high tech flywheel magneto.
Here are all the numbers I recorded just now. Sorry for the late response.

For ground on the final test I used the battery ground terminal, battery not on the bike for any of these tests.

Font Slope Darkness Terrestrial plant Screenshot
 

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That all looks good except for the stator itself. I've actually not seen numbers like that before but can tell you it is fubar. The 5/9 is low and that's fairly typical with these failures but the exceptionally high 8/9 is weird and suggests corrosion or other damage to the link between the high and low speed coils. {pins 8 + 9}.

One last test not covered in the motofaction test if you don't mind. Test the three yellow charge wires for continuity to pin 9.
 

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Discussion Starter · #10 ·
That all looks good except for the stator itself. I've actually not seen numbers like that before but can tell you it is fubar. The 5/9 is low and that's fairly typical with these failures but the exceptionally high 8/9 is weird and suggests corrosion or other damage to the link between the high and low speed coils. {pins 8 + 9}.

One last test not covered in the motofaction test if you don't mind. Test the three yellow charge wires for continuity to pin 9.
No continuity between A,B,C and 9
 

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Discussion Starter · #11 ·
Post your numbers and we'll have a look. The test needs to be done on 2K ohms as if done on 200 ohms the numbers above 200 will be incorrect but I'm assuming your meter is maybe auto ranging as some of the numbers that say correct are above 200 and the fail {5/8} is generally below 100.
As far as testing resistance on 5/8 at 2kohms I just read out 607
 

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5/
As far as testing resistance on 5/8 at 2kohms I just read out 607
That's also weird and I can't account for it other than to say - FUBAR.

I expect the power output is quite low and the cylinder that is the path of least resistence gets the spark. But I would also swap plug/plug cap and coils left to right one after the other to see if the fault follows as your pulsers etc have tested OK.
 

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Discussion Starter · #13 ·
5/

That's also weird and I can't account for it other than to say - FUBAR.

I expect the power output is quite low and the cylinder that is the path of least resistence gets the spark. But I would also swap plug/plug cap and coils left to right one after the other to see if the fault follows as your pulsers etc have tested OK.

I've swapped the coils both ways, as well as putting new ones on, and it was always the same thing. Originally when I first found the problem, or encountered it, it was a fine spark on the right and no spark on the left. Now it's a weak spark on the right, none on the left still. That could have to do with the fact that I only had the battery hooked up to my car running off the jumper cables. Battery is probably no good.

As far as the funny numbers, I have a $20 performance tools multimeter from O'Reilly Auto Parts. I wouldn't put way too much trust into it, just that it will get a somewhat accurate reading, but not a precise one.
 
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