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Discussion Starter #23
put the mixture screws back to 1.5 turns out from lightly seated
after watching your viideo i have to ask are you sure the rae san control box is properly grounded ?

the box must be on a good clean ground or grounded with a wire attached to the box
Yes, I tried resetting the mix on the carbs to 1.5 rotations once lightly seated and there was little impact to how the bike runs. I also swapped carbs after resetting this with no change in how the bike runs.

The box is bolted down to bare steel (the ends of the bracket are painted) in my electronics tray which you saw in that video. There are four screws holding it down, although I have not tested continuity to frame I am confident that my ground is good. However, I’ll go and verify that now! Thanks.
 

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Discussion Starter #24
after watching your viideo i have to ask are you sure the rae san control box is properly grounded ?

the box must be on a good clean ground or grounded with a wire attached to the box
Here’s some photos of the mounting plate for the Rae San and the advancer position.

I spoke with Ray over email (who was very kind and understanding, he even refunded the price + shipping of the hall plate) and he thinks this mounting plate and position is more or less appropriate. Very grateful for this community and product developers like Murray and Ray, the generosity and eagerness to help is sincerely appreciated.

I will update this thread whenever possible.
 

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I didn't see you mention swapping the plug caps left to right. I've had high resistance in old plug caps, even after the brass rod mod.

Randall

EDIT: I just reread your first post, and you did cover that. Sorry.
 

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Discussion Starter #26
I didn't see you mention swapping the plug caps left to right. I've had high resistance in old plug caps, even after the brass rod mod.

Randall

EDIT: I just reread your first post, and you did cover that. Sorry.
All good, I appreciate the thought you gave! Thanks.
 

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Not sure if you gave this a try already but I had the exact same issue and after trying almost all the same tests it turned out to be the fuel lines. Try pulling the left fuel line off the carb. It could be filling enough to start but once running can’t keep up. Was tough positioning the splitter to get good flow to both.
 

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Hi all,

Issue: CX500 idles with left cylinder firing intermittently at idle and dies if left idling. Right cylinder fires well and regularly.

I tried my best to aid all weakness of the CX motor (1979 Standard 23k all stock to start), here’s what I’ve done:

* Tightened cam chain: had rear engine cover off: tensioner had been the plenty of life left and replaced mechanical seal

* Set the hall plate again and again: made ignition adjustments repeatedly despite the lack of flywheel markers but timing seems good enough to run well - also made rough 2mm adjustments to magnetic rotor per Ray’s manual as well.

* Compression tested: 120+ PSI both sides

* PCV routed to fuel lines and breather filter per motofaction article. Seems to work well.

* Ignition components: replaced spark plug wires, coils compatible with 12v kit linked from Ray’s site, did brass rod mod, grounded ignition control unit to chassis, used recommend (by Ray via email) ignition curve.

* Switched carbs: used Murray’s carbs side to side to no affect. Carbs switched made absolutely no difference. Also cleaned both carbs throughly.

* Switched coils: Switched coils and wiring (meaning left sparks with right timing etc.) then coils with factory wiring with no major impact to idle. Left and right spark plug caps and wires were also switched.

* Adjusted idle speed: tightened/loosened idle screws to ensure that idle speed was not too low/high to run.

* Bought new spark plugs: Occam’s Razor - hoping the simplest issue is causing biggest problem. Also replaced the left spark plug wire and adjusted spring in left cap. No change.

My bike is obviously not stock, and that’s part of my issue. There aren’t many threads on this. Murray is very helpful, but I feel that my issue is no longer his responsibility... I feel guilty holding him hostage on the phone.

The bike ran GREAT with the full CDI system and CV carbs.

Please feel free to contribute any ideas, silly or not. I think I could possibly have a loose ground or wiring issue, although it’s strange that the issue is localized to the left cylinder.

Please help!
I did almost exactly what you went through... I swapped 3 times the carbs, I broke down again the original carb and cleaned it again, I'm going nuts here and went through the carb manual and it states that the most difficult part and the easiest to correct is the idle jet and sure enough there was a spec of crust lodged in there. I looked at the other carbs and the same! This is what threw me off; the carbs worked well on my other CX500! o_O
 

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Discussion Starter #29
Not sure if you gave this a try already but I had the exact same issue and after trying almost all the same tests it turned out to be the fuel lines. Try pulling the left fuel line off the carb. It could be filling enough to start but once running can’t keep up. Was tough positioning the splitter to get good flow to both.
Hmm, the bowls on each carb get filled entirely so I assume that they’re both getting fuel just fine - I did wrestle with getting the fuel lines set up when I first got the carbs in, but I’ve verified that both carbs are getting enough fuel now. Good thought, though, thanks for the input!
 

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Discussion Starter #30
I did almost exactly what you went through... I swapped 3 times the carbs, I broke down again the original carb and cleaned it again, I'm going nuts here and went through the carb manual and it states that the most difficult part and the easiest to correct is the idle jet and sure enough there was a spec of crust lodged in there. I looked at the other carbs and the same! This is what threw me off; the carbs worked well on my other CX500! o_O
Did you have the original Keihin carbs or Murray’s? I cleaned the carbs over and over (plus I only got them a month or so ago) and swapped them side to side many times, not thinking that they’re the issue at this time, but I appreciate the thought.
 

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Hi all,

Issue: CX500 idles with left cylinder firing intermittently at idle and dies if left idling. Right cylinder fires well and regularly.

I tried my best to aid all weakness of the CX motor (1979 Standard 23k all stock to start), here’s what I’ve done:

* Tightened cam chain: had rear engine cover off: tensioner had been the plenty of life left and replaced mechanical seal

* Set the hall plate again and again: made ignition adjustments repeatedly despite the lack of flywheel markers but timing seems good enough to run well - also made rough 2mm adjustments to magnetic rotor per Ray’s manual as well.

* Compression tested: 120+ PSI both sides

* PCV routed to fuel lines and breather filter per motofaction article. Seems to work well.

* Ignition components: replaced spark plug wires, coils compatible with 12v kit linked from Ray’s site, did brass rod mod, grounded ignition control unit to chassis, used recommend (by Ray via email) ignition curve.

* Switched carbs: used Murray’s carbs side to side to no affect. Carbs switched made absolutely no difference. Also cleaned both carbs throughly.

* Switched coils: Switched coils and wiring (meaning left sparks with right timing etc.) then coils with factory wiring with no major impact to idle. Left and right spark plug caps and wires were also switched.

* Adjusted idle speed: tightened/loosened idle screws to ensure that idle speed was not too low/high to run.

* Bought new spark plugs: Occam’s Razor - hoping the simplest issue is causing biggest problem. Also replaced the left spark plug wire and adjusted spring in left cap. No change.

My bike is obviously not stock, and that’s part of my issue. There aren’t many threads on this. Murray is very helpful, but I feel that my issue is no longer his responsibility... I feel guilty holding him hostage on the phone.

The bike ran GREAT with the full CDI system and CV carbs.

Please feel free to contribute any ideas, silly or not. I think I could possibly have a loose ground or wiring issue, although it’s strange that the issue is localized to the left cylinder.

Please help!
Hi all, I also had firing problems with my 1979 CX500d and after many different tries and many different threads I finally found 1 that said these bikes have a known problem with the coils. Changed the coil that is not firing correctly and have had no problems since. Best of luck,
Wayne
 

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Discussion Starter #32
Hi all, I also had firing problems with my 1979 CX500d and after many different tries and many different threads I finally found 1 that said these bikes have a known problem with the coils. Changed the coil that is not firing correctly and have had no problems since. Best of luck,
Wayne
When I got the Rae San system I changed my coils out for 12V coils linked on Ray’s site, and even when swapping the coils from side to side they behaved no differently... I appreciate the thought, though!
 

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Discussion Starter #33
UPDATE 06.23.20

New hall plate is installed thanks to Murray, and bike now will rev through the range with no issues but left cylinder continues to drop out for idle and will cough and pop unless I yank the throttle again to bring it back to life. No idea what to do now, but I’m gonna start by tweaking the carbs a bit, I suppose
 

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Discussion Starter #34
So I reset ignition timing again and played with carbs. seems like left cylinder drops out if I make it idle below 2000rpm but happily comes back to life if I raise it to 2k or more
 

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Seek advice from Murray before tweaking the carbs.
 

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Discussion Starter #36
I have a basic understanding of how the VM34s work and we’ve chatted a couple times about the carbs in respect to my specific issue, so I appreciate the comment but I understand everything I’ve changed on them so far.
 

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Discussion Starter #37
Update 06.30.20

Murray is sending me a replacement ignition, I think it’s another one of Ray’s designs. We’re stumped on the issue. I’m also ordering an Ignitech; I’m hopeful that this is somehow all my fault, but if my issues are at the fault of Ray’s ignition, I can no longer trust the Rae San kits. I have had the following issues with my Rae San 12V kit:

  • lopsided hall plate made ignition pulses out of time
  • hall plate broke upon installation
  • ignition system sends pulse signal to one cylinder when key is moved from off to on without cranking, which is sort of dangerous
  • when key is left in the on position, the ignition will sometimes send a pulse signal to one cylinder, causing to repeatedly spark and drain the battery. this killed one lithium ion battery of mine.
I have spent roughly $500 (kit, coils, stator, tools and parts to diagnose, etc.) trying to get this ignition system to work on my bike to no avail. The ignition system has had issues since it was out of the box. Feel free to reference the videos I’ve linked in this thread.

OTOH, Ray has been very responsive, apologetic, and has refunded me for defective parts. It’s obvious that Ray has good intentions, but in my experience, the product is not of acceptable quality. The bike has sat for months because of this issue, to the point where I set idle at 3k the other day and took it for a long ride anyway, where the ignition functioned perfectly, hilariously enough. However, lower the idle to be under 3k and the bike dies.


I’ll give an update when I get a new ignition system in the bike.
 
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