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Hello everyone....



Bike: 1980 CX500C. About 23K miles. Charging went out during the final ride of the season last year.



Just put the engine back in after replacing the dead stator and pressing in a new water pump mechanical seal. Cam chain and guides look like new.



I can't get the bike to start. Ran excellent before pulling the engine.



Have plenty of gas and spark. On a lark, I swapped the L and R coil wires. It starts on one cylinder.



Is is possible I reversed the L and R pulsers when I re-assembled? I thought they only fit one way....



Thanks in advance.......
 

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Its possible, as physically the L pulser will fit into the R pulser socket

and vice versa.

I have a pair of CDI pulsers here and have just been looking at them

and if you have swapped them and L is now R and assuming both pulsers are AOK

I'd say that functionally it should still work as long as you swapped the

coil wires over so each side gets its sparks at the correct time.

the fact you have one side running is encouraging.

A stator test as found in the quick reference section is the first place to start

and the loss of one side could be due to many things.
 

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Could you have installed the pulser off 180 degrees? I believe it can be done and might explain why it runs when you swap the coils as that is close to a 90 deg swap (our V twins are 88 deg or so) and might make the other cylinder work.
 

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Reg, I'm not sure the coils will receive the input signal at the right time if the pulsars are reversed inside the rear case. I've been trying to roll this around my empty head to try to follow the progression. Even if you reversed the coil wires, I think they would still be out. I wonder if the "wasted spark" is now firing the engine?



I'm going to sleep on this one, maybe get the wife to research it while I nap.
 

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I was kind of thinking what if you pulled the opposite wires out of the cdi connector and reversed the left and right.
 

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Reg, I'm not sure the coils will receive the input signal at the right time if the pulsars are reversed inside the rear case. I've been trying to roll this around my empty head to try to follow the progression. Even if you reversed the coil wires, I think they would still be out. I wonder if the "wasted spark" is now firing the engine?



I'm going to sleep on this one, maybe get the wife to research it while I nap.




I was kind of thinking what if you pulled the opposite wires out of the cdi connector and reversed the left and right.


Blue Fox, I wondered the same thing, would swapping the coil wires correct the problem if the pulsars are wrong. My first thought was that it would,,but the more I thought about it I began to have doubts.

I was not sure and I figured the same as Blindstitch, switching the CDI input wires from the pulsars and connect the coil wires the proper way would for sure make it correct.



Then as I thought about it some more I think that Reg is correct after all, and switching the coil wires should work. It is tricky to try and visualize it but I think that it should correct the problem.



But if it does, why is it only running on one?



Mayor John,,I think on a GL you can install the pulsar out 180,, but I don't think it could happen on a CX.
 

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He should be able to tell if he's reversed the pulsers on assembly by checking to see if the timing datum line is visible on the right pulser through the timing cover as this line only appears on the right pulser.



I tend to think this isn't the case as the internal wires become quite stiff with years of being fried in oil and likely wouldn't want to lay in in any other way than the way they have become used to, - but you never know.



EDIT: On further thought it would be possible to reverse the pulser wires connections while hooking up the new stator IF they were in fact disconnected.



Having changed from a G47 to a G8 though I don't see any reason these would have been disconnected'



These wires do become brittle and will snap during handling [has happened to me].



Suggest do the tests on the pulsers.
 

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He should be able to tell if he's reversed the pulsers on assembly by checking to see if the timing datum line is visible on the right pulser through the timing cover as this line only appears on the right pulser.



I tend to think this isn't the case as the internal wires become quite stiff with years of being fried in oil and likely wouldn't want to lay in in any other way than the way they have become used to, - but you never know.


Good idea!
 

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It had me scratching my head until I looked at them

I've laid them out on some paper.

As you can see, even if they were swapped the brass 'tit' on the rotor

would still sweep past the low and high speed coils in the correct order

but the L would be firing for the R and vice versa

So I'd say if the CDI coils outputs were swapped to compensate for this

it should still run.



The broken cable idea sounds feasible as I agree they probably wont like

to be yanked about too much.

A stator resistance test should tell if this is the case



 

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Reg, what concerned me was will the spark come at the right time? I would think that the crankshaft/valve train is looking for the spark to happen 30 degrees before or after it is really getting it. It would get the spark in the right order, but not quite at the right time. I don't know, it is probably just an exercise in mental gymnastics, as this may not be the actual problem.
 

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Theoretically, to me any alteration to the wiring would need to be done BEFORE the CDI box to be effective.



Also, I think the only difference between the pulsers is the datum line and L and R cast into them. Internally I'd bet they're the same.



If this was a parallel twin with redundant spark it wouldn't even be an issue. It is the 80 degrees that would disturb me simply swapping the P and Y coil wires.
 

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I cant say I've thought through every step but

as they're held in the same fixed position on the rear cover

in relation to the brass tit thing and the high and low speed

pulser coils get swept in the same order

then timing wise, there's no change and I dont see that as an issue



Assuming we have two identical channels in the CDI box

all we'd get is the L firing in place of the R and vice versa

so as long as the output from the CDI to the coils is swapped as well

I reckon it should run.



( stops to think and scratch head)

Its just occured to me that on a std bike this may not work quite that well

after all



What could cause a snag is when the advance coils come into play

they are electruically 'invisible' for want of a better term

until the rotational speed causes them to generate enough of a voltage

to trigger the CDI sooner than the std pulsers

This would trigger say the Left channel (which is now the right) at the wrong time

and early in the left compression stroke, when due to the swapped

pulsers, we need it early in the right.

( I know its confusing aint it?)

In this case I'd say it would work up to around 2000 rpm befor the advance coils

start to bugger it all up so perhaps swapping the advance ooil terminals over as well

would be needed



On an Ignitech system where the advance coils are ignored it may not be

much of a problem.
 

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The workings of a black box are a dark mystery to me but I see what you mean about the advances, have they effectively became retards? Wouldn't rev past the RPM point where advance would normally begin to take place 2 - 3 grand?



The same wiring swap would then need to be made to the wiring of the advance pulsers?
 

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Yeah, because of the advance spark, changing the coil wires will not work.



If he swapped the input wires from the main pulsars before they connect to the CDI it should work though. He would have to swap the coil wires back.
 
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