Honda CX 500 Forum banner
1 - 12 of 12 Posts

·
Registered
1979 CX500c
Joined
·
18 Posts
Discussion Starter · #1 ·
Hi guys,

I'm new here. Just acquired a 1979 CX500 Custom. I have plans to bring this thing back to life. It seems to be pretty clean for its age and the fact I rescued it from a life of neglect in a buddy's backyard. This is my first bike so I'm looking for a little guidance. I want to update the electrical system and want to make sure I am replacing components with products that are compatible with the bike. My main areas of concern at this point are the regulator rectifier and the CDI unit, both look like they have seen better days. Are these generic units or do I need to look for specific specs? What products have you guys replaced your regulator rectifiers and CDI units with that have been successful? I attached a pic of the bike in its current state.

Thanks for any information!
 

Attachments

·
Super Moderator
Joined
·
5,665 Posts
I suspect from the picture that you haven't yet had the bike running? I'd suggest that getting it running should be your first objective. Then you will know if any parts need replacing. Many CX500s are still running with the original CDI and regulator/rectifier.
 

·
Registered
1979 CX500c
Joined
·
18 Posts
Discussion Starter · #3 ·
I suspect from the picture that you haven't yet had the bike running? I'd suggest that getting it running should be your first objective. Then you will know if any parts need replacing. Many CX500s are still running with the original CDI and regulator/rectifier.
That's correct. My original plan was to start the engine first but I found a lot of the terminations were not made and several wires were broken. To be fair, I didn't even try because I thought the system would be too far gone. Maybe I will just rewire the essentials for now to test the engine. I would still like to replace those parts because they are pretty ratty looking and I'd just rather do it than not.
 

·
Super Moderator
Joined
·
5,665 Posts
Ratty looking on the outside does not necessarily mean ratty on the inside. These units (R/R and CDI) are well sealed.
If you must throw cash at your bike then look into the Rae-San ignition system and a series type MOSFET R/R and while at it a GL500 stator.
 

·
Registered
1979 CX500c
Joined
·
18 Posts
Discussion Starter · #6 ·
Ratty looking on the outside does not necessarily mean ratty on the inside. These units (R/R and CDI) are well sealed.
If you must throw cash at your bike then look into the Rae-San ignition system and a series type MOSFET R/R and while at it a GL500 stator.
Touche. I judged it strictly on its age and appearance. I do like to update things to new condition so I will look into those suggested components. Thanks for your suggestions
 

·
Registered
Joined
·
60 Posts
I would run the stator test first then you can see what your options are for electronics. If the stator test checks out and the CDI box is bad you can go with Ignitech or Rae-San. Also for wiring look at NWT cycletronics. Have used them and really simplifies the wiring.
 

·
Registered
1978 CX500 "The Grub", 1983 GL650I "Nimbus"
Joined
·
12,077 Posts
I'd want to know I have a runner before buying expensive upgrades, unless you determine through testing that a component is bad.
 
  • Like
Reactions: D-Fresh

·
Registered
Joined
·
1,670 Posts
you should download the FSM in nolimitz sig line as well as the other two links in his sig line. Another good resource is the following: The Honda CX and GL 500 and 650 family of motorcycles (motofaction.org)

In my case i did a compression check on the engine that came with the bike and it was abysmal so i pulled the heads only to find a complete mess so it was better to get a donor engine. I then made sure it's compression was good and got it running before i started working on it (still in progress but that's another story). You have the added complexity of the hacked up wiring so you have to deal with that first, unfortunately.
 

·
Super Moderator
'84 CX650E that is evolving into a GL500
Joined
·
18,410 Posts
Welcome to the forum 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 even before it sat and someone started taking it apart 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. 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).
Your bike still has the original rubber brake line, which should have been replaced every 2 or 3 fluid changes (= 5 or 6 years) and stopping is even more important than starting so I recommend shopping for a modern stainless braided line (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).

The best advice anyone can give you about customizing any vehicle is to get it safe & reliable in more or less original condition and use it for a while before you start making any changes so it can tell you what changes it needs to make it do what you want/need better. That approach almost always results in something you actually want to keep and use but making changes based on style or on what someone else (who may or may not really understand how the changes affect the way it works) has done often results in a piece of expensive yard art that you can't stand sitting on for more than a few minutes and might even be dangerous.

Also (since this is your first bike) take a Canada Safety Council motorcycle training course before you start playing in traffic. It WILL save your life many times over (not to mention making it easier to get your license). Sign up early because the courses tend to fill up fast in normal times and I suspect they will fill even faster this year with Covid restrictions being lifted
 

·
Registered
1979 CX500c
Joined
·
18 Posts
Discussion Starter · #11 ·
My plan was to drop the engine and go through it because I am not sure what was and was not done. I plan to follow the FSM for this. Would you guys waste time dropping the engine out and tearing it down if you were in my position or would you start it first despite all the electrical problems. Thanks for the knowledge guys, like I said this is my first bike. I have experience working on cars and industrial machines so I have a little bit of useful background. This is definitely the oldest vehicle I’ve gotten into.
 

·
Super Moderator
'84 CX650E that is evolving into a GL500
Joined
·
18,410 Posts
I'd try to start it before I went too far with anything else. If it runs OK it would make sense to continue but if find a serious problem you'll have to make some big decisions. While anything can theoretically be fixed it might not be worth the effort & money required and you might not be able to find a suitable replacement within a reasonable distance.
 
1 - 12 of 12 Posts
Top