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Hi all , dodgy cx running real bad after 5k revs , reading a lot on here about resistors in leads and caps , forgive my ignorance but I’m new to classic bikes (apart from my rd350lc)
The guy who sold me the bike when I quizzed him said he replaced the coils, ht leads and plugs to Honda’s spec so do u all think I can rule out conflicting resistors making the bike jerk over 5k revs ?
thanks
 

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81 Gl500i 83 CX650E
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Hi Phil , depending on the year of your bike two common problems are showing up. Cdi ignitions failures and second dirty carbs ( as in the mainjet getting restricted , get Larrys famous carb book). Myself clean carbs first , ( cheapest) and replace resisters with a piece of brass rod.
 
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You can easily check the plug caps with a multimeter...they just unscrew.. give em a good shot of contact cleaner and dry before refit....
 

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Had exactly the same symptoms on my TAI bike and the cure was new spark plugs, new ignition leads and lots of scraping and cleaning to clear the electrical path from the plug cap lead connector screw, through the spring and resistor to the spark plug connection screw.
 
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'84 CX650E that is evolving into a GL500
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These links may help:
Note that all CX500 models/years except the CX500E (Sport or Eurosport) and the 1982 model CX500C (Custom) came with Capacitor Discharge Ignition (CDI) and the models mentioned plus the GL500 and all CX/GL650 came with Transistor amplifier Ignition (TI or sometimes TAI). But 40 years is a long time and more than a few of these bikes have had the engine replaced with one from a different model or year and we've seen a few early CX500s with TI engines.

(Some models came with resistors in both the spark plugs and the spark plug caps and that didn't cause any "conflicts" but you really don't want resistor wires on any bike)
 

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'84 CX650E that is evolving into a GL500
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You have now started 3 threads about the same problem. Multiple threads about the same problem (even if attacked from different angles) are frowned upon because it gets confusing when people answer in one thread without reading the others or without realizing that they are all related.
I considered merging them but I think in this case that would only make it even more confusing so I am posting links to the other threads in each of them instead.

I strongly recommend reading all 3 threads before replying in any of them.


 

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1978 CX500 "The Grub", 1983 GL650I "Nimbus"
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Note that all CX500 models/years except the CX500E (Sport or Eurosport) and the 1982 model CX500C (Custom) came with Capacitor Discharge Ignition (CDI) and the models mentioned plus the GL500 and all CX/GL650 came with Transistor amplifier Ignition (TI or sometimes TAI). But 40 years is a long time and more than a few of these bikes have had the engine replaced with one from a different model or year and we've seen a few early CX500s with TI engines.
Outside North America, didn't the later CX500 Standard switch the TI at some point Probably around 1982)?
Based on the engine serial number in one of the other threads, this appears to be a '78 or '79, therefore CDI.
 
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