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Discussion Starter #1
I have an interesting dilemma in that i rode the cx500 home yesterday, turned it off in the shed and it was running fine. Went to start it today and there is no spark at all on either plug. I have a Raysan module that shows there is pulsing out to the coils. Coils have connectivity to earth. Other than both coils failing together, which i consider most unlikely, does anyone have any suggestions ?
 

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Discussion Starter #2
I should also add that the connector to the raysan unit is intact to both sides
 

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12v conversion or cdi ?
12V conversion - check there is 12V at the coils -
CDI - check power and grouinds to the gy6 modules

Rayman
 

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Discussion Starter #5
It is the CDI unit. The green LEDs are flashing but both red LEDs are now off. Only one was lit before and now neither red one is on. Any thoughts ?
 

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ok - the only time ive see nthe actual advancer unit fail is either over / reverse voltaged or physical abuse from being mounted such that the seat pan smashes into it on bumps -
it doesnt sound like that -
you wont see the red leds unless its running at speed as the individual pulses are too short fro the human eye -
it sounds like you have a busted power or ground connection to the gy6 modules -

do you have a multimeter - I would check for contiuity of ground and power connections at the gy6 modules first up.
 

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Discussion Starter #7
Thanks for the help so far Ray. Both GY6 modules have power to them and both are showing to be earthed using multimeter. Coils also have continuity to both primary and secondary circuits. I am lost !!! Help needed!
 

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renriv how did you check for spark? The valve covers do not provide a good ground.
 

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Discussion Starter #10
If both green LEDs are flashing alternately and strongly I assume this means there is a pulse getting there from the Hall Unit. At the output wires from the driver unit to the coils a digital multimeter shows varying voltage output. Both GY6 modules and the control module are showing to be earthed. Coil shows a spark when i open and close a circuit with 12V power. Is there a way I can check the output from the driver to the coils ? Do I need a CRO to do this ?
 

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have you disconnected the wire from the kill switch - its souding like the kill switch wire has shorted to the frame or the switch is corroded >
you are correct - flashing greens indicates triggers from the hall are good -
the trigger pulse to the gy6s is only 0.5ms long - so would be hard to see with a multimeter - given that its both it has to be a common element - power - ground or kill switch.

Cheers
Rayman
 

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Discussion Starter #12
Thank you Rayman ! It was the kill switch !!!!!! How stupid do you think I feel. I thought the kill switch killed all power and the starter wouldn't work either. Thank you everyone for your help too.
 

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:)
 

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Has anyone installed an indicator light that illuminates when the kill switch is off when the ignition is on? Could save some future grief.
 

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'84 CX650E that is evolving into a GL500
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FWIW, the kill switches on Hondas (and other makes too) co not prevent the starter motor from operating. It is sometimes useful to be able to crank the engine with the ignition (the parts that make sparks, not the keyswitch) turned off.
 

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FWIW, the kill switches on Hondas (and other makes too) co not prevent the starter motor from operating. It is sometimes useful to be able to crank the engine with the ignition (the parts that make sparks, not the keyswitch) turned off.
With the vacuum actuated pet-cock this is indeed useful. If my bike has been sitting for a few days, i crank for a few seconds with the switch off, vacuum opens the petcock, bowls fill, switch ignition on and it starts with less than a rotation of the starter.
 

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The vacuum produced by cranking with the starter isn't enough to open the vacuum valve far enough to let the bowls fill quickly. It is better to whack the throttle open quickly a couple of times before starting so that the accelerator pump squirts a bit of raw fuel into the throats of the carbs, allowing the engine to start and run enough for the petcock's vacuum valve to open fully.
 

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There is enough vacuum created to fill the float bowls in the time it takes the oil light to turn off. I prefer the way that Abes describes because of the build up of oil pressure before the engines fires. I agree also that wacking the throttle will get it started quickly too unless you have an early cx without an accelerator pump. I have changed to a non vacuum petcock but will still run the starter until the oil light shuts off before turning the kill switch to run when the bike has been sitting for more than a couple of days.
 

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The vacuum produced by cranking with the starter isn't enough to open the vacuum valve far enough to let the bowls fill quickly. It is better to whack the throttle open quickly a couple of times before starting so that the accelerator pump squirts a bit of raw fuel into the throats of the carbs, allowing the engine to start and run enough for the petcock's vacuum valve to open fully.
It opens mine just fine. I've drained gas out for a friend who ran out on the highway, pulled the fuel line off the carb, put it in a water bottle, cranked over and got a steady stream.
 

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Early CX500s without accelerator pumps don't have vacuum petcocks so it doesn't matter.

I guess it's a matter of opinion whether extra strain on the battery & starter or having the engine run for a couple of cycles without full oil pressure is worse on the machine as a whole. I figure unless it has been sitting for a long time (months or years) there should be enough oil film to protect it until the pressure comes up if the engineers knew what they were doing.
 
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