Stators

[kirrbby]

This thread is to give me a place to post up info about the various stators that we find on little Honda's.

Please contribute to this thread if you have good info, or questions, or anything to add.

First up is a 3 wire Mitsubishi stator from a CT70 HK0.

It looks pretty good, except someone replaced the points wire with a generic green, with a loop, instead of the stock open ended connector on a black wire.

Removed from the plate.
You can see the end of the yellow wire comes out of the center area of the winding. So I'm saying that it is one of the TWO "center tap"s that come out of the lighting coil.

 

[kirrbby]

At the other end of the lighting coil, there are 2 wires coming out. One is soldered on to the steel core of the coil. The other wire is the one that goes to the primary coil. I believe this is the other center tap...but it's just a wild guess...can't tell for sure.

Why did they connect the lighting coil to the primary coil??

These pics shows the end of the winding. It is a soldered connection to the green wire that goes out to the modular plug.

 

[kirrbby]

This is the primary coil.
I don't see anywhere that the copper winding wire is soldered to the steel core of the coil.
One end...the start of the winding is soldered to the wire from the lighting coil.
The end of the winding gets soldered to the condenser.

 

[kirrbby]

I uncovered this "soldered connection. It doesn't look soldered at all, but more like stranded wire that's twisted and crimped.

 

[kirrbby]

I found a Mitsu coil that is rough enough to be a good candidate to unwind. I still have questions about the lighting coil, and don't yet have all of the info I'd need to be able to duplicate it. So I'll do that and post up what I find. That should finish up for this stator. Probably sometime this week.

 

[BlueGrassTornado]

I uncovered this "soldered connection. It doesn't look soldered at all, but more like stranded wire that's twisted and crimped.
View attachment 56688

I found that exact same wire in the exact same condition! Remember I posted I thought it had been "smushed" behind the coil by accident? I ended up just putting a shrink wrap connector over it and leaving it alone, some have said this is a ground????

 

[kirrbby]

Ya, I figure that has to be how the primary coil grounds...it gets it's ground thru the lighting coil's ground...which is where the lighting coil winding is soldered to the steel core. Kinda odd to me that they did it this way, and I'm wondering if there is a reason.

 

[kirrbby]

I unwrapped my rusty Mitsubishi lighting coil. Here's how it's done.

They started by soldering the copper wire to the steel core. They start at the leading end...the end that the magnets pass first as the flywheel spins counterclockwise...on the lighting coil it's the end near the condenser.
They solder it on and pull the wire lengthwise to the opposite end of the steel core, then cover it with a insulating plastic sheet. Then they made some wraps of wire to hold everything in place.

The last pic shows the first "center tap" that splices in. There is about 3' of wire on the coil before they made the first splice. This is the splice that gets attached to the wire from the primary coil. It's a stranded copper wire.

 

[kirrbby]

So they wrapped a few feet of wire and then tapped in a wire to go to the primary coil. Then they covered that connection with another insulating sheet.
Seen in this pic.

Then they wrapped another 23' of wire, and made the 2nd splice, or "center tap". This one goes to the yellow wire, which powes the headlight circuit.

That splice was then covered with the insulator plastic/paper sheet. Then they wrapped another 26' of wire onto the coil before they cut it, and soldered it onto the green wire. You can see that connection on the good stator that I pictured in the first few posts. Both of the soldered connections we're rotted off of THIS particular coil...but you can see them on the first coil. The green wire is the battery charging circuit.

 

[allenp42]

Remember I posted I thought it had been "smushed" behind the coil by accident? I ended up just putting a shrink wrap connector over it and leaving it alone, some have said this is a ground????

Yeah, I was one of them, and would have bet money. Glad I didn't.

So they wrapped a few feet of wire and then tapped in a wire to go to the primary coil. Then they covered that connection with another insulating sheet.

Not sure what to think of this. Maybe a pre-charge, pre-boost, or something to give the primary coil a little more "oomph"? Purely a WAG on my part. Will have to put on a Jethro thinking cap and might have to use a lifeline as well. Hope racerx knows......

Nice job Kirb, There is NO WAY you could figure this out by using run of the mill multimeters.

 

[69ST]

Integrated function, IOW structural and operational. There are more windings feeding the yellow AC headlight lead and they used a few of them as a strain relief; at OEM level, the cost savings adds up quickly. It's not strictly necessary to solder the ground lead to the laminations but, that soldered joint will never oxidize and develop resistance. IMHO it's a very resourceful method of ensuring longevity.

If I were rewinding these coils, I'd use heavy-walled shrink tubing and epoxy to insulate & secure things. I'd preferentially go with a floating ground on the lighting coil, along with a full-wave reg/rec. That'd give you full alternator output, in 12VDC flavor, with everything powered from the battery. That means real headlighting and your choice of LEDs...if desired. Best, edumacated, guess is that you'd gain at least 25% total system capacity...maybe more with additional windings. Also note how neatly and tightly the windings are; that's very important. For most guys, this is OTT. Replacement coils are readily available for everything but the Mits 4-speed stator...and they're cheeep.

 

[kirrbby]

I wanted to unwind this coil for a couple reasons I guess...

One was just to see how they did it.. answer all of the questions that can only be answered by unwinding for a look. From here we can figure out how it "works".

If someone wanted to duplicate the coil as closely as possible to stock...this tells you what it takes. It doesn't HAVE to be done this way to work...there's more than one way to find a good result...lights. But there's only one way for a hard core purist who wants to keep his bike pure.




I would like to have a Honda drawing of this Mitsubishi stator to post here in this part of the thread. But I do not think one exists...only drawings of the Hitachi version.
If I can decipher how Honda WOULD HAVE drawn it...if they did, I'll scribble one myself. More on that later.

I don't like how Mitsubishi spliced in the center taps without soldering them. I'm surprised these stators don't fail more often. If I were to duplicate this coil, I'd solder those connections.

If I were rewrapping a complete Mitsubishi stator from scratch, I wouldn't do that connection between the two coils. I think I'd just start with a ground loop on the leading end of the winding...on both coils. Or, a soldered ground connection...for the sake of simplicity.

racerx, your idea of wrapping a 12v, full wave, floating ground, Mitsubishi stator...from scratch, is on my list for my Scrappy Softail. We're gonna see how that works out, eventually.

 

[kirrbby]

Here's a juicy tidbit.

It seems these Mitsu stator/flywheels ARE coded. Notice the H-
H seems to be the CT70H version of the stator.


I have some G's, which seem to be from CL70'S.

I have one that's a D.
I marked it when I bought it...(from a C70 Cub, from the UK)

 

[allenp42]

I was surfin' this rainy evening on www.daxshoppen.dk and noticed a few things that peaked my interest.

CDI Replacement for the Mitsubishi flywheel. Not sure if it's correct for a H Mitsu setup, but it looks the same.
https://www.daxshoppen.dk/mitsubishi_6v_contactless_ignition-p-2639.html

CDI Replacement for the Hitachi flywheel. Not sure if it's correct for a H Hitachi flywheel, but it sure looks the same. The control module looks a little different than one from Malaysia (xrarespares)
https://www.daxshoppen.dk/hitachi_6v_contactless_ignition-p-2644.html

Aftermarket replacement stator for Hitachi. Not sure if it's for a 3 speed or 4 sp, but it "looks" more like the 4 sp. version.
https://www.daxshoppen.dk/hitatchi_ignition_plate_85_mm_6_volt-p-1588.html

They are not cheap, but if I manually do the currency conversion and remove the 25% VAT, not too much higher than xrarespares.

Anyone know if the ST50 & ST70 flywheels are the same as used on HK0 & HK1?

If there are no red flags, then I may send them an e-mail and inquire on shipping.....and currency conversion. FYI - You have the option on their website to show the currency in USD, Kroner and Euro. However, I don't know often they update the exchange rate, but the USD prices were a lot higher than I expected.

 

[OLD CT]

That Mitsu setup has 5 wires. I have never played around with a 5 wire setup. How do you make that work?

 

[allenp42]

Good catch Pat. I think I see 5 wires on the Hitachi version as well. It may have do with the CDI module, but that's a purely a guess on my part. I'll probably shoot them an e-mail and ask a few questions. For sure, I want to confirm if it works with the flywheels from an H. Maybe I can get the installation instructions, which it says come with the kit, that could help answer a few questions.

 

[OLD CT]

Now that is a good point, I see the xrare setup has 5 wires. It's been a long time since I installed one on my bike and forget where the instructions are . I am interested if the Mitsu kit works.

 

[kirrbby]

2 hot wires, a ground, trigger, and spark. I don't know how the trigger gets...triggered, on this setup tho.

 

[69ST]

2 hot wires, a ground, trigger, and spark. I don't know how the trigger gets...triggered, on this setup tho.

A little more specifically: lighting, charging, ground, trigger (to CDI module), primary coil output. Looks to me like most of the sorting is already done...match the bullet connectors from the stator to the module and you should be left with the lighting, charging & system ground leads.

As for how the system is "triggered", it's based on the magnetic pulse as the flywheel spins. With the magnets & coils in known positions, relative to crank rotation, it's relatively easy to "program" the module. It's the same principle used with automotive timing lights...the type that can be "dialed-back".

 

[allenp42]

Update: I sent an e-mail last week to ask a few technical questions and get an idea on shipping costs, and haven't heard back. I just noticed they have a "contact page" where you fill in a form request, so I sent another message this evening.