Can anyone tell what ignition this is

[Pacman91]

Hi everyone, so I just found this ignition on eBay last night and bought it right away because it was a steal. I had thought it was a version of the dynatec electronic ignition but after when I looked online nothing similar showed up anywhere. The says it was for a 78 to 80 GS750. Screenshot_20190317-225710_eBay.jpg

So anyone have any idea what brand or model this is so I can hopefully get some set up instructions?

I also hope the image has loaded properly as I'm have issues uploading pics.

[GregT]

Whatever it is,it's a simple switch type as it still uses the centrifugal advance.
I've not seen the almost full circle surround before - and wonder if it's an optical trigger.

[Grimly]

From what I can make out, the rotor has a couple of opposed humps on it, so likely a magnetic trigger each side.
It might drive the coils directly (like Dyna), or it may need an ignitor box to go with it (like Piranha).
Looking at the size of the modules and gauge of the wiring, it's quite likely akin to a Dyna in operation, so if you're lucky, it's all there.
There's no guarantee the wiring colours mean anything, except to the maker.

[bwringer]

When you get it, we'll need some better pictures. PotatoVision and poor lighting doesn't give us much to work with.

I do know Dyna ignitions have changed appearance a few times, but I don't recall ever seeing one that was a full doughnut shape. Or maybe it's more of a "U" shape with some unknown widget at the top?

[Pacman91]

When you get it, we'll need some better pictures. PotatoVision and poor lighting doesn't give us much to work with.

I do know Dyna ignitions have changed appearance a few times, but I don't recall ever seeing one that was a full doughnut shape. Or maybe it's more of a "U" shape with some unknown widget at the top?

Ya when it comes in I'll upload some better pics for sure. I was already needing to buy a new advancer so worked out great for the all in price of $90 cad

[bobgroger]

Looks like a Dyna S to me... I have 3, they work as advertised. There are 2 different GS ones depending on the OEM and year, I think the rotating part is the difference

[Pacman91]

So here is what just came in the mail today and I've never seen this design. It looks like a complete circle but looking in from the bottom where the wires come in it looks like 2 separate pieces just like the average dynatec but with some type of heat shrink cover.

[Pacman91]

20190405_234324.jpg

This is the governor that it came with

[bwringer]

OK, that's weird. I got nuttin' -- I haven't seen anything like that before. The wire colors are definitely not Dyna.

That's a stock mechanical advancer, but it's missing the rotor or trigger bit.

On a Dyna ignition, you get a black plastic trigger unit that has a magnet embedded in it. And on the stock GS ignition, there's a metal bit with a sort of fin sticking out that triggers the pickups as it goes past.

It should be easy to get a stock trigger; you remove it when you install a Dyna, so there are plenty floating around.

But unless we figure out who made that ignition, it's impossible to tell what sort of trigger unit you'll need.

[Pacman91]

Ya I know what you mean about the trigger needing to be plastic. I have a good normal trigger. This afternoon hopefully I can get this on the engine and see if it triggers anything.

[Steve]

Unless you have some other indication of what the different color wires mean, I would <guess> that those mate up with the stock colors: orange is power, black and white to the coils with the same colors.

.

[GregT]

Unless you have some other indication of what the different color wires mean, I would <guess> that those mate up with the stock colors: orange is power, black and white to the coils with the same colors.

.

Agree. I have to say that the backplate looks Dyna but the pickups look homemade.
I'd try it with a Dyna S type rotor - plastic with imbedded magnet.

[bwringer]

Agree. I have to say that the backplate looks Dyna but the pickups look homemade.
I'd try it with a Dyna S type rotor - plastic with imbedded magnet.

No need to bother mounting it on an engine; you could hook up power and a test light with test leads per the Dyna instructions and try waving a small magnet to see if it switches.

http://www.powercommander.com/downloads/Support-Released/Dynatek/Manuals/DynaSTSG.pdf

If not, then you'll need to check resistances to see if it's just a sensor with a separate ignition box somewhere (that you don't have).


If it switches, then it's likely a complete ignition al la Dyna. Given the size of the pickups and the wires, I suspect this is how it works.

[twowings]

That looks like a Prestolite ignition.

[Pacman91]

No need to bother mounting it on an engine; you could hook up power and a test light with test leads per the Dyna instructions and try waving a small magnet to see if it switches.

http://www.powercommander.com/downloads/Support-Released/Dynatek/Manuals/DynaSTSG.pdf

If not, then you'll need to check resistances to see if it's just a sensor with a separate ignition box somewhere (that you don't have).


If it switches, then it's likely a complete ignition al la Dyna. Given the size of the pickups and the wires, I suspect this is how it works.

So I actually checked that trigger that it came with and found that it is mildly magnetic ( it has a weak magnetic pull as tested with metal key ring). So I tried to do the test with a magnet and with just the trigger and as I move it around the individual sides I can see that it is switching on to each coil. I actually just had the bike fire up for the first time today since I've rebuilt the engine that was seized for the past ~7 years so I'm just riding that high for now. I'll try switching over to this new ignition from the points sometime in the next month when I hopefully have the rest of the bike put together.