1982 Honda NU50 - No Spark/Ignition Key Issues/Stator Issues

Josh Abbate /

So I have been given a Honda 1982 NU50. I have no idea what I'm doing, it hasn't ran in 10+ years, is missing parts, and I'm very much learning on the fly, particularly from posts here and youtube videos.

My overarching issue is that I have no spark. I have at this time replaced the CDI, Ignition Coil and spark plug. From what I can tell these are all the most common problems.

And then I discovered that I was missing an ignition key. When i found the connector for the key however, it has more wires than in the wiring diagram. On the diagram it has a black with white tracer, a red, a green and a black. However, mine also has 2 black with red tracer wires.

After searching online, I believe that I could put these together to bypass the switch. I put the black and red wires together. Then disassembled the off/run/off switch to connect the greens together and the black with white traces together. Which left me with the 2 mystery black with red tracers...which I put together, because I have no idea what I'm doing. I believe this is all correct. So if it isnt, please let me know.

Unfortunately after connecting them all, still no spark. So I bought a new ignition key which stated it would work on a NU50. However, when it came, it only has a red, green, black with white tracer and black that 2 wires can plug into. Can I use this switch? How? Should I just continue to ignore the mystery black with red tracer wires and leave them together?

Ultimately, as this still produced no spark, I thought I probably have a more serious issue and despite reading that it was very rare, I moved on to checking the stator. From the video I watched, I checked continuity on all the wires. My meter reads the continuity and beeps for every wire coming off the stator, except the black with red tracer wire coming off the stator. The black with red tracer wire goes to one side of the stator while all the other wires go to the other side (and the blue in the middle). I thought I possibly had a break in the wire so I examined it completely and theres no breaks. When I go from one end of the wire to where it is soldered on to the stator it does beep, which implies to me that the wire itself has continuity and the issue is with that section of the stator specifically.

I have found a new stator on ebay, but I wanted to make sure before I pulled the trigger on it that someone more experienced than I am agreed that my stator is likely at fault here.

I have included pictures of the wiring system I got going on. I'm sorry they aren't more clear. Additionally I included a picture of the stator and a close up of where I am placing the meter to get continuity on the black with red tracer wire. I'm sorry for this wall of text, I'm not sure how much info to include.

At this point any help would be immensely appreciated.

Wiring diagram: https://www.mopedarmy.com/forums/file.php?6,file=59706

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Re: 1982 Honda NU50 - No Spark/Ignition Key Issues/Stator Issues

holy crap. that looks like a nighmare, wtf is goin on in there!

anyway, what you can do is try just hardwiring it to see if it'll spark.

you should have a generic 5 pin cdi, with a pin-out like the one pictured here:

https://www.mopedarmy.com/wiki/Hobbit_CDI_Wiring#Generic_5_pin_CDI

from that you should be able to connect on the CDI box only the AC input and timing pulse from the engine stator, a ground to the engine, and the power out to your ignition coil. Do not connect anything to the middle bottom "kill switch" pin's wire. Then connect your coil ground and see if theres spark. if so, you've confirmed its a wiring issue and you can either trace it down in the stock wiring loom or just hardwire up your own power and ignition setup.

Re: 1982 Honda NU50 - No Spark/Ignition Key Issues/Stator Issues

Josh Abbate /

It certainly is a mess. I am learning a lot about electrical problems though. So..theres that.

I will definitely try your suggestion. I get absolutely no reading of any kind off my meter on the black with red tracer wire coming off the stator, while I do get a reading (both an ohm reading and a continuity reading) off every other wire. I just cant help but feel that isnt normal.

I will update once I give it a try! Thank you for the help!

Re: 1982 Honda NU50 - No Spark/Ignition Key Issues/Stator Issues

Josh Abbate /

So I gave it a try. I believe it's the same process followed here (

). Additionally, I got a decent deal on a new stator. So I threw that in there too.

And... still no spark.

I'm growing discouraged. I really felt I'd have spark by now. Anyone with absolutely any ideas or suggestions, even just pointing me in a possible direction, would be a great help.

Re: 1982 Honda NU50 - No Spark/Ignition Key Issues/Stator Issues

I've solved a Honda spark problem fixing the wiring harness where it exits the mag housing. Had to remove the clamp and pull the wires into the housing to find the bared wires.

Re: 1982 Honda NU50 - No Spark/Ignition Key Issues/Stator Issues

yeah, the block wall of text is annoying. keep it short

By the picts, this ignition has been messed with from PO.

theres two coils on stator plate. lights and ignition

the tiny one is your trigger coil, damn, ok theres three coils on stator plate.

concentrate on trigger and ignition. two wires for trigger and one for ignition

Ignition coil. Ensure continuity between stator plate (ground) and end of black/red wire. If not, pull it off and check for a loose/cut short wire. If you can not get continuity from one end to the other then replace.

Once installed and continuity tests good. Spin motor up, you should get some voltage from black wire to ground. Volt meter on AC.

review, so to get spark you need that power from ignition coil to cdi and the two trigger connected as stated above. ground as well off cdi.

NO spark?

high tension external coil. MUST grounded to frame. Does not matter if brand new or old. Ensure continuity between plug cap and power in. If not then inspect piece by piece. Cap to wire, wire to wire, wire to HT coil , Ht coil to small spade terminal.

That's it, good luck.

Re: 1982 Honda NU50 - No Spark/Ignition Key Issues/Stator Issues

Captain Janeway /

Are you using right switch for right bike? Nu506 uses a 4 prong, NU50M uses a 6 prong. See manual here. Wiring diagrams for both are here

https://drive.google.com/folderview?id=1vxdUocvohov-VU1KVuOY-9YquFpw7fok

Re: 1982 Honda NU50 - No Spark/Ignition Key Issues/Stator Issues

Josh Abbate /

First, sorry for the wall of text.

I did as the above and still no spark. I checked the continuity of everything and I have continuity everywhere coming off the stator. My meter beeps on every wire but I have a .204 reading on the black and red wire. However, I dont think that should prevent me getting spark.

I do have voltage coming out of the black and red wire when I give it a kick.

What I dont have is continuity on the new external coil between where power goes in and where the spark plug goes in.

I'm guessing that my new external coil perhaps just came bad?

I do think I bought the wrong key. I have a 6 prong one coming!

Let me know if I've misread the situation!

Thank you!

Re: 1982 Honda NU50 - No Spark/Ignition Key Issues/Stator Issues

There needs to be resistance ( not continuity ) between all three terminals on the secondary coil to induce spark. Your coil is not faulty.

Re: 1982 Honda NU50 - No Spark/Ignition Key Issues/Stator Issues

voltage out on black red is good.

untwist your spark plug cap and wire and test individually for continuity or resistance. pict might help.

Re: 1982 Honda NU50 - No Spark/Ignition Key Issues/Stator Issues

Josh Abbate /

I had continuity on the spark plug cap end, as well as the wire running from the coil to the spark plug cap, however I didnt have continuity from the power in on the coil to where the wire goes into the coil.

I can take pictures tomorrow if needed!

If it's resistence I should have measured for and not continuity, I admittedly did not test for that and would have to check it tomorrow.

I really appreciate all the help.

Re: 1982 Honda NU50 - No Spark/Ignition Key Issues/Stator Issues

that coils no good, get another one.

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