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Discussion Starter · #1 ·
I tested the coils by switching them at bullet connectors, and which ever one that was connected to the reddish\pink wire had no spark. The one on the yellow wire sparked good.



Could I be looking at a bad CDI unit? Is there a way to test the CDI? Not sure what my next move should be. THANKS!
 

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I think you'll need to borrow a good cdi from somewhere to find out if your is fubar.



But before that, try new plugs, try cleaning the plug caps.



Have to ask the silly question - when you swapped the bullets, did you remember to also swap the HT leads over to the other cylinder?
 

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I tested the coils by switching them at bullet connectors, and which ever one that was connected to the reddish\pink wire had no spark. The one on the yellow wire sparked good.



Could I be looking at a bad CDI unit? Is there a way to test the CDI? Not sure what my next move should be. THANKS!


Probably the CDI but I suppose it could be a bad right pulsar too.



You could check the resistance readings,,see this thread at shep's site

http://globalcxglvtwins.hostingdelivered.com/viewtopic.php?f=17&t=521
 

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Discussion Starter · #5 ·
I think you'll need to borrow a good cdi from somewhere to find out if your is fubar.



But before that, try new plugs, try cleaning the plug caps.



Have to ask the silly question - when you swapped the bullets, did you remember to also swap the HT leads over to the other cylinder?




The plugs are brand new. I'm not sure what you mean by HT leads. I only see 1 wire coming out of each coil, and they plug in back under the seat by bullet connectors. I did physicly switch the coils over



but then realized that was stupid just for doing a spark test on the frame. I didn't try and start the bike with the wires switched over, I was just checking for spark. I THOUGHT I would find that the right



coil would still have no spark if I swapped it over and plugged it into the yellow wire behind the seat, but I found that it now did have spark and vise versa. The coil on the left now had NO spark when plugged



into the other side. I also don't see how the plug caps are having anything to do with it. (Which ever coil is connected to the yellow lead has a fine spark)
 

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Discussion Starter · #6 ·
Is there a way to test a cdi with a multimeter? I'm starting to feel this could be my problem but don't want to throw money at a used one before knowing for sure. Riding season is quickly drawling to a close on me and I



really want to get this bike running before I have to put her up. Thanks guys. ( also, what years of cx bikes would have cdi units that would work for my 78? )
 

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Is there a way to test a cdi with a multimeter? I'm starting to feel this could be my problem but don't want to throw money at a used one before knowing for sure. Riding season is quickly drawling to a close on me and I



really want to get this bike running before I have to put her up. Thanks guys. ( also, what years of cx bikes would have cdi units that would work for my 78? )




78-81, i believe
 

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HT = high tension. These are the wires from the coil to to the plug.



I thought you were trying to start the bike with the coils swapped over, so just reminding you to swap the thin wire AND HT leads :) and leave the coils bolted to the frame to get their ground connection.



'Which ever coil is connected to the yellow lead has a fine spark' - this is the clincher. Nothing wrong with the coil, caps or plugs.



Any luck borrowing a working CDI for a test?
 

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Discussion Starter · #10 ·
HT = high tension. These are the wires from the coil to to the plug.



I thought you were trying to start the bike with the coils swapped over, so just reminding you to swap the thin wire AND HT leads :) and leave the coils bolted to the frame to get their ground connection.



'Which ever coil is connected to the yellow lead has a fine spark' - this is the clincher. Nothing wrong with the coil, caps or plugs.



Any luck borrowing a working CDI for a test?




Thanks for the replies guys. I don't know where I would borrow one. Yeah, I was reading on an older post how a bike



starts acting when a cdi starts to take a dump and it sounds exactly like what happened to me. The bad news I have



found out is that these cdi's are hard to find at a decent price. Guess I will just have to keep looking.
 

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Thanks for the replies guys. I don't know where I would borrow one. Yeah, I was reading on an older post how a bike



starts acting when a cdi starts to take a dump and it sounds exactly like what happened to me. The bad news I have



found out is that these cdi's are hard to find at a decent price. Guess I will just have to keep looking.




Well if your willing to put out about 150 or 160 cobram has a CDI replacement that will also help mitigate some stator problems. It works great. It is not OEM, but it is brand new (not 30+years old) and comes with a 2 year warranty. It is also plug and play.



ignitech Cobram is a little under the weather so it may take a bit for him to reply.



It is just an option if it is the CDI that is out. Which it looks like it is.





PS: you could pick up this guys.
 

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I would *HIGHLY* suggest you go through those resistance tests.



I had no spark on my left side, turned out my left pulsar (pick up coil) was dead.
 
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