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Discussion Starter · #1 ·
Well i got the gl500 running today, I cleanded carbs and cleaned tank.

installed a filter, made sure its folowing the right way.

it fires up runs great for about 2 minnuts or so then the idle goese downlike it wants to die, like a hiccup in idle, then it goes back up.

vacume lines are all good. and petcock is good and gas filter is full of gas.



I am leaning tourd bad resistors (ie caps) I think i can hear them arcing in the head, but it would seam that then it would run crapy all the time.

any guesses.
 

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cycle-man,



Interesting that you would mention a hiccup. My GL500 does the same thing. If you've just gotten yours going, there may be any number of gremlins causing it, but mine was running good since I got it and then after a couple of months I started noticing that sometimes while sitting at a light I would hear a slight clunk and the rpms would go low enough that I thought it was going to die. At first I caught it with the throttle, and it seemed like if I keep it at 1500-2000 rpm it doesn't do it. Mine occurs randomly, but pretty predictably every 30-60 seconds while idling. Like yours, mine recovers immediately without dying, but it does make me go, "Hmmm". I have a spare set of carbs that I'm going to put on next time I get a couple of minutes, and if that doesn't cure it I'll start looking deeper. They did just start running ethanol in the gas here -- Hmmm.
 

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Well i got the gl500 running today, I cleanded carbs and cleaned tank.

installed a filter, made sure its folowing the right way.

it fires up runs great for about 2 minnuts or so then the idle goese downlike it wants to die, like a hiccup in idle, then it goes back up.

vacume lines are all good. and petcock is good and gas filter is full of gas.



I am leaning tourd bad resistors (ie caps) I think i can hear them arcing in the head, but it would seam that then it would run crapy all the time.

any guesses.


Can you detail how you cleaned the carbs? I am new the CX500 & picked up Larry's rebuild book, went through the whole process step by step, and he indicates that the center Jet can cause problems with idle if it is not cleaned properly. Just a thought. Might be worthwhile cleaning it out? A #1 Tap Extractor to pull it, and a .018" drill bit to chase the ports.



This bike hasnt ran since 86, After the carb rebuild, she started in less than 2 minutes, I haven't even sync'd the carbs yet and she purrs right along.
 

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"A #1 Tap Extractor to pull it, and a .018" drill bit to chase the ports."



At some point in OEM history the "pressed in" jets were changed to threaded jets, as I recall. Check yours for a slot, if they are slotted they are threaded, and a tap extractor is not needed (or desirable
) I'm just not sure if this only applies to 650s.
 

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There are many little gremlins that cause our engines to run inconsistently or poorly...or worse. I would suggest doing a 20k maint interval and inspection as per the shop manual. Go through all the simple stuff first, then go to the diagnostic procedure outligned in the manual... For me, it has usually been the simple things. Or a Complete no warning CATASTROPHIC failure.



a rough or inconsistent idle is not usually catastrophic so I would not be worried... too much



Already on this thread, we have everything from plug wires to carb jets and gas cap vents... It could be one of these, a combination, or something completely unrelated like an intermittant electrical component that is affected by heat or vibration.

In the shop manual is a flow chart for troubleshooting these type issues. See the quik Ref threads going to "forums" these are an invaluable resource as all manuals and parts fiches are there for the downloading...



As has been mentioned many times, the proper electrical grounding of Coils and other circuits is very important and if intermittant will make your bike act as if possesed by Wotan's mechanic... the honda facto literature does not go into too much eletrical trouble shooting other than continuity and voltage measurements. I don't think they ever mention the shake test while performing these measurements... so an intermittant physical connection might be tough to find if all you do is touch leads and look at the meter. Just like spraying stater fluid around the airbox to look for vac leaks, (gently) shake the connector blocks while the motor is running, give a little tug here and there on the grounds...



30 yrs is a long time for copper wire in hostile environments... add bi-metalic joiners and electroylisis. they may look good on the outside, while black and unconductive on the inside...



All my BS aside... plspardon...



If I gotta guess, ';-0,,, I think it's a sticking float ( float stays up, fuel is gone, idle goes down, float eventually falls, prob goes away, under speed float does not stick as it's vibrating like all get out ) That's my .02, .01 whatever it takes!
 

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Discussion Starter · #7 ·
ya i tried with gas cap of

and i have rebuilt many carbs

I follow the rick massy method in xj web sight.

I had a cx before so and did that carb, this bike was running last year so the carbs were realy clean as it was.

I think it almost seams like it maybe it is an electrical deficancy like it runs then maybe it is losing volts for a sec so it idles down then pick right back up.



But it could also be fuel related, but its weird that it would run about 1 minut then idle down then back up then run fine for the same time then idles down.

i would think that if it was a fuil problem that it wouldnt be so precise on the rithim. that it would run crappy then good for longer durations but I dont have enough experiance with this system.

I would also think if it was cap-resistors that it would run good then when they get warmed up run bad, not up and down?



but if there is a bad ground or a week link in the elctrical system somewere that was causeing it to lose volts to the coils ie caps that would do it. ALSO THE STARTER IS HOT, COULD THE STARTER BE DRAWING JUICE? AND WHAT WOULD HAPPEN IF IT DID, WOULD IT BE INERMITENT?



THANKS I AM GOING DOWN TO GET NEW CAPS TODAY I WILL BE BACK IN A HOUR OR SO AND POST WERTHER THAT HELPED.
 

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Hope that starter motor is not stuck "ON" - it should not get hot - unless you crank it for 3-4 minutes - then it will..
 

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"A #1 Tap Extractor to pull it, and a .018" drill bit to chase the ports."



At some point in OEM history the "pressed in" jets were changed to threaded jets, as I recall. Check yours for a slot, if they are slotted they are threaded, and a tap extractor is not needed (or desirable
) I'm just not sure if this only applies to 650s.


...thanks on this one,...just sharing my experience is all, and it was...well very 79CX500C specific!
 

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