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Discussion Starter · #1 ·
Hey everyone, extremely hopeful to find a specialist mechanic to resolve some gremlins in my 1980 cx, which I bought 6months ago. Completely stumped on getting her rideable again. Any experts in or around London would be amazing? Thank you for any leads! :)
 

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Welcome...(y)

What are the issues-?no spark......?poor performance.
There is a myriad of diagnostic tests you can do with basic tools.
Good luck with the project....

Post technical questions under "Technical Help Forum" as thats scanned by the more knowledgeable members routinely
 

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Discussion Starter · #5 ·
Gremlins? We could use a bit more information to help you.
Thank you.

This is from my friendly mechanic who had a brave go over he past month ...

The bike has been stripped of all its diy wiring. Ive established a new loom, as per Rae-San's instructions, and the wiring diagram for this bike. The only circuits present now are the charging/starting/ignition circuits. Ive done this to be 100% certain that a short in the rest of the bike was the source of the problem.

The bike will start on the button, and while I'm not overly impressed with the idle, ( pod air filters don't help) it will continue to idle until I connect the positive and negative feeds from the regulator to the bike's battery.

Interestingly the idle isnt affected by the regulator being connected to a 2nd battery separate from the bike, whiuch rules out interference between the stator and the hall effect sensor adjacent to it

With so little wiring and components, we can narrow down the components likely to be at fault. Loom, Battery, reg, stator, ignition pick ups, ignition, coils and cdi's.

I've tripled checked the way Ive wired this up, soldered all the joints and checked for continuity where it should exist. I dont think its the loom. Ive tried several different batteries, three different regs ( the latest of which Ive blown by clumsily connecting the charging wires to a battery the wrong way round without a fuse in line...doh)

The stator is doing its job, and the fact that (pre-reg blowing incident) it will happily charge an auxillary battery at a handsome 14.4v without affecting the idle suggests that there is no interference between the stator and the pick ups.

I have bought new , verified DC cdis from a very knowledgable chap selling on ebay, which when fitted, behaved worse than the originals. With the new cdi's in the bike would start, but wouldnt rev at all, the slightest throttle and it would die, suggesting an issue with timing advance? Certainly this eventuality hasn't helped, rather hindered the diagnosis.

Given the coils, leads and caps were original, and one of the connections to the coil from the ht lead was questionable, Ive fitted new coils, leads and caps, which hasn't made the slightest bit of difference.

That leaves Mr Rae-Sans ignition set up. In an ideal world I'd just replace it, but at 180 dollars (plus a new reg of course), and the fact it has to come from the states, AND the fact that this bike has left me so confused I wouldnt bet my life on it solving the problem, I have called time on it.

...

There's a lot there. Sorry. But you can probably see why I need to find an uber specialist.

Thank you a million for any ideas.

Rog
 

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1978 CX500 "The Grub", 1983 GL650I "Nimbus"
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The bike has been stripped of all its diy wiring.
So, you aren't starting with a stock harness? Taking on someone else's botched project isn't an easy task, and diagnosing a non-stock system via description only is nearly impossible. Pictures of what you have would help immensely.

I have bought new , verified DC cdis from a very knowledgable chap selling on ebay, which when fitted, behaved worse than the originals. With the new cdi's in the bike would start, but wouldnt rev at all...
The '80 model should have one CDI unit. A later TI model will have two igniters (little silver-gray boxes), but they aren't CDIs. Again, pics would help.

That leaves Mr Rae-Sans ignition set up. In an ideal world I'd just replace it, but at 180 dollars (plus a new reg of course), and the fact it has to come from the states...
Ray is in Australia. Maybe you bought it through Murray's Carbs?
 

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Our biweekly Zoom meet up begins in just over an hour (9:00 CDT).
Join us there, and we can discuss your project.
 
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I have bought new , verified DC cdis from a very knowledgable chap selling on ebay

What?
a 1980 has only one CDI
unless like my '79 er it has a later TI lump with 2 spark units

I've never seen 'new' CDIs for the earlier CXs anywhere and cant think
why someone would bother developing and selling them now when Ignitech
and Raesans are available.

sounds iffy to me I recked he's flogged you a couple of cheap scooter DC CDIs
cos he knew sfa about how the CX AC CDI ignition system actually worked.

I bet like a lot of folk here, if it were in front of me I'd probably diagnose it
before you came out the house with the tea and biccies.( its only a CX after all)
but online diagnosis is like pulling teeth without good, accurate descriptions
and terminology and lotsa good pictures.
 

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I have bought new , verified DC cdis from a very knowledgable chap selling on ebay

What?
a 1980 has only one CDI
unless like my '79 er it has a later TI lump with 2 spark units

I've never seen 'new' CDIs for the earlier CXs anywhere and cant think
why someone would bother developing and selling them now when Ignitech
and Raesans are available.

sounds iffy to me I recked he's flogged you a couple of cheap scooter DC CDIs
cos he knew sfa about how the CX AC CDI ignition system actually worked.

I bet like a lot of folk here, if it were in front of me I'd probably diagnose it
before you came out the house with the tea and biccies.( its only a CX after all)
but online diagnosis is like pulling teeth without good, accurate descriptions
and terminology and lotsa good pictures.
Often referenced your earlier posts Reg....your posts offer a good easy to understand reference.(y)
Might need to give the OP a lil slack tho'. ;)....maybe photos as you say or if Roger attends the link-up that will clarify things.
But agree the mechanic quoted makes some worrying statements....
Possibly UK members could recommend a local person that could have a look at reasonable rates.....?
 

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The OP has indicated that the bike has a Rae-San ignition, hence the two cdis. At least I take that to be the case from "...The bike has been stripped of all its diy wiring. Ive established a new loom, as per Rae-San's instructions, and the wiring diagram for this bike..." in post #5.
 

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ok - sounds like the other CDIs were not the correct type - and were firing on the wrong edge of the pulse - there are several variants around that look the same.

it Soulds like a either -
a grounding issue - and when the battery is connected the grounds are changed -
or a noise issue -
the PO may have reverse polaritied the advancer - which will have hurt the power supply filtering -
likewise - running the system without a battery connected is not healthy - the battery is part of the filtering for the power supply and stops the voltage from thje stator spiking beyond the 15V mark - without that you are liucky you havent blown the advacner - or you may have damaged it -

As has been said - diagnosis without pictures is next to impossible - if you can showt he wiring I might be able to point somehting out

Rayman
 
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'84 CX650E that is evolving into a GL500
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I was wondering if it had TI and he had fallen into the misuse of the term "CDI" to describe any electronic ignition whether it is Capacitor Discharge Ignition or not (this seems to be very common in the UK and Silver's lists the TI spark units as "CDI/Spark unit").

BTW: Welcome to the forum. Please add your location to your profile and your bike's model and model year (NOT year first registered as UK paperwork shows) to your signature so that you don't have to remember to tell us every time and we don't have to keep asking when you forget (see Forum Settings link in my signature).

And welcome to the world of antique vehicle ownership (they own us, not the other way around). Your bike is about 4 decades old and, aside from your current problems, the Previous Owners may or may not have done the maintenance necessary to keep it safe & reliable so it is highly recommended to download the Factory Shop Manual for your model (available through the CX Wiki - link in my signature) and go through all of the service procedures, regardless of whether your bike has reached the specified mileage.
I also recommend looking on all rubber parts with suspicion because rubber does not age gracefully. Check the date codes on your tires and replace them if they are over 5 years old no matter how good they look & feel (old rubber simply cannot flow around the irregularities in the asphalt well enough to grip, especially if it is cool or wet). If your bike still has the original rubber brake line(s) (should be replaced every 2 or 3 fluid changes = 5 or 6 years) I recommend shopping for modern stainless braided ones (they last practically forever and double the life of the fluid). And don't forget things like the rad hoses and the boot between the engine and swingarm (they can crack on the bottom where you don't see it).
 

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it could be a TAI to CDI conversion - but without pictures I cant tell -
Rayman
 
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