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Discussion Starter · #1 ·
So I purchased a 1979 Honda CX500 and it was missing the CDI box and the Engine cover to the Ignition points located at the back of the engine case under the carbs.

I went ahead and purchased a set of Murray's Carbs, Murray's coil-on plug kit, and the Rae-San CX CDI to 12V coil Conversion Kit.

The bike still wont start and I have a few questions:

1) Do I need any other adapters such as the Rae-San LS2 Adapter module and/or CDI TACHO ADAPTOR?

2) Does this system completely replace the old CDI box?

3) is there somewhere else that may be influencing the bike not starting?

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for starters - you have purtchased the 12V conversion kit which requires 12V tai style coils - NOT MURRAYS CDI COPS.
The COPS can be driven by the cx Hall Full kit as it has CDI outputs -
you'll either need to change the driver box to be the CDI version + gy6 modules - or change the coils to 2.5 to 4 ohm TAI types.

Cheers
Rayman
 

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Discussion Starter · #3 ·
for starters - you have purtchased the 12V conversion kit which requires 12V tai style coils - NOT MURRAYS CDI COPS. The COPS can be driven by the cx Hall Full kit as it has CDI outputs - you'll either need to change the driver box to be the CDI version + gy6 modules - or change the coils to 2.5 to 4 ohm TAI types. Cheers Rayman
is either coil type superior?
 

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Discussion Starter · #4 ·
for starters - you have purtchased the 12V conversion kit which requires 12V tai style coils - NOT MURRAYS CDI COPS.
The COPS can be driven by the cx Hall Full kit as it has CDI outputs -
you'll either need to change the driver box to be the CDI version + gy6 modules - or change the coils to 2.5 to 4 ohm TAI types.

Cheers
Rayman
Also, hypothetically speaking: could I order a set of these coils for one of the following TI models?

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any of those would work fine, as will Harley Davidison Signle fire coil packs (clones), Riscks 23-103 coils etc.

CDI draw less power - so ytou are ok without the stator upgrade - they give a shorter spark, more intense,
TI coils have a leeser peak spark intensity but of longer duration.

in these applications not a lot of difference - when running higher rpm - CDI are easier to achieve and maintain the spark energy as rpm go beyond about 12000 Rpm.

Rayman
 

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Discussion Starter · #6 ·
Update:

installed coils from a GL500

battery is charged

gas is flowing to the Murray carbs

new ignition module is lighting up and the kill switch relay is working properly

new spark plugs installed and gap is to specs

The starter works great the bike turns over quickly but the bike does NOT fire up or even sounds close…

Could this issue be electrical? I checked the fuses and all of them are good 👍🏽

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'84 CX650E that is evolving into a GL500
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Do you have spark? Are the plugs wet after attempting to start it?

The thing with the prongs (part of the brake light switch maybe?) may not be causing this problem but it will surely cause other problems in the future.
And for heaven's sake move that regulator/rectifier before it melts the wiring harness. Those fins on it are not just to make it look good but because it can get hot (fins = more surface area to dissipate heat). It needs to be located where there is good airflow past the fins and bolted down securely.

BTW, I seem to have missed this when you joined so welcome to the forum. Please add your location and your bike's model and model year to your profile 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 in spite of the changes that have been made to it may or may not have had all of 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. Your tires look pretty new but it wouldn't hurt to 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).
It always amazes me when someone makes all sorts of changes to a bike without addressing something as basic as replacing the original rubber brake line. They really should be replaced every 2 or 3 fluid changes (= 5 or 6 years) so I recommend shopping for modern stainless braided ones (they last practically forever and double the life of the fluid).
Of course, that won't matter if the line isn't connected to the master cylinder....

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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that stress on the cables of the rae-san controller is asking for trouble in the short term. wires should not be under stress and especially not on a vibrating platform.
reguulator needs to be properly mounted not hanging in the breeze..

where have you wired the second wire to the coils too - probably ground ? incorrect. needs to go to the +12 ignition power -
i cnat see the coil wiring in the pictures - but thats the most common mistake people make when fitting the 12V coils -

Rayman
 

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Discussion Starter · #9 ·
Do you have spark? Are the plugs wet after attempting to start it?

The thing with the prongs (part of the brake light switch maybe?) may not be causing this problem but it will surely cause other problems in the future.
And for heaven's sake move that regulator/rectifier before it melts the wiring harness. Those fins on it are not just to make it look good but because it can get hot (fins = more surface area to dissipate heat). It needs to be located where there is good airflow past the fins and bolted down securely.

BTW, I seem to have missed this when you joined so welcome to the forum. Please add your location and your bike's model and model year to your profile 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 in spite of the changes that have been made to it may or may not have had all of 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. Your tires look pretty new but it wouldn't hurt to 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).
It always amazes me when someone makes all sorts of changes to a bike without addressing something as basic as replacing the original rubber brake line. They really should be replaced every 2 or 3 fluid changes (= 5 or 6 years) so I recommend shopping for modern stainless braided ones (they last practically forever and double the life of the fluid).
Of course, that won't matter if the line isn't connected to the master cylinder....

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).
thank you for all the suggestions! I will be pulling the spark plugs again on Friday and checking for oil inside that well. I know we used marvels mystery oil to unseize the engine.

all electronics under the seat are in temporary locations and will be building a electronics tray. We just wanted to make sure the bike starts up fully…before continuing :)

also, is there a certain brake hose you recommend? Or what should I search for? Length wise…etc
 
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