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Discussion Starter · #1 ·
Hi all, I've had a '78 CX 500 for a few months now and have really enjoyed it, despite a few issues.

One of which is how it looses power and bogs down at 5000 rpm. I can nurse it through at first, but as the bike gets warmer, 5000rpm becomes in impenatrable wall. Doesn't happen when the engine is cold.



I think I need a new coil and I've heard of Ignitech modules that just need 12v and dont care about the ignition windings of the stator. That's what I would prefer; just to skip the "what if its the stator?" question.



Also, is there a difference between this Ignitech system and a regular automotive ignition coil? I could rig up something probably, but if this Ignitech is plug and play I'll go with that.



Big question: where can I buy the Ignitech CDI box? Local Honda dealer?
 

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Go ahead and get the ingetech sounds like the high side of the stator is gone get the ingetech and you wont have to worry about that well worth it and if you get it through Cobram they are like 80 or 80 dollars cheaper than just buying one by urself.
 

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Discussion Starter · #5 ·
I just pulled the seat and tank and I saw only one box under the seat. I'm assuming its the cdi module, but I expeccted to find two boxes. So if the stator provides power for both high and low rpms, does the same cdi module handle both also. I also saw the two coils up under the tank. I unbolted and sanded the surfaces of every connection that could have possibly been for grounding that I could easily reach, but I just rode for about 20 min. and the problem persists.


I asked Cobram about the ignitech and am awaiting a response. I'll try to keep updates coming so that others with this issue will have a reference to go by.



Just to reiterate, all is well when engine is cold. I can full throttle it(if i chose to) up to 9000rpm with only perhaps a small hesitation at 5000rpm.

When the engine warms a little it bogs and sputters at 5000rpm exactly. From that point I cannot ask for any significant power through about 5000 to 6000rpm. But its fine above that range. After a while I cant even nurse the bike past 5000rpm and after about 30 min of riding I loose power over the entire rpm range to the point that I can't accelerate. Also, the engine has extreme difficulting restarting when its warm or hot.



And though I wouldn't trust it entirely, my temp gauge doesn't work; so I dont even have a ball park on what temp. I'm reaching.
 

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Sickwayne - Several have indicated a 'proper' carb cleaning may be the solution. I, too, have paid for a carb cleaning and did not get results a couple of years ago. It seems most mechanics work on the more contemporary stuff and not familiar enough with these 30 year old carbs to get the job done right. Consider getting Larry's book, or at least, probe the threads on carb cleaning. You may be pleasantly surprised with the results.



Where are you located. Perhaps someone here is close enough to come and assist you more directly.



Good luck.
 

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Discussion Starter · #7 ·
I'm in Hudson, NC. Its near Hickory (if any knows the location). I agree. I ran all this by an old college professor of mine, a literal genius with cars/engines, and he said point blank "You have a weak spark problem AND a poor fuel delivery problem."



Its hard to say to a mechanic who does this for a living and know way more than I do, "I know you said you cleaned thee carbs, do it again please."
 

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Discussion Starter · #9 ·
I just bought a spark gap tester to measure the gap when all is well and then again when the engine runs rough. While testing the left cylinder I noticed the battery's negative wire was loose. I mean FLOPPING LOOSE!!! I tightened it, replaced the plugs, and of course measure the spark at its maximum length. Fairly strong spark compared to a car. Afterwards I went for a trouble-free perfect 30 mile ride! No problems whatsoever! I have trouble believing that the battery's bolt could be that loose for 3 months without backing completely out, but who knows!
 
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