Coil compatibility?

[Magua]

I've got a new coil for my bike, but unfortunately the wire colours of the new don't match with the old. Trial and error or am I going to fry something if I connect them up wrong?

1980 cb400n btw.

[tri boy]

Post if it's a genuine coil or not, and the primary wire colours.
Is it second hand? Off what?
Is it for your CB?
Throw the team some info.

[Magua]

Non genuine coil, new. https://www.davidsilverspares.co.uk/parts/part_28546/
Black and black with a white stripe on the new, one green and one yellow on the old. For my 400, cb400n 1980.

[tri boy]

The colour coding on your new one could be difficult to decide upon.
Can you email the supplier?

Other option would be to use a multi meter to check wire resistance between it, and the coils iron mount/base.
ie: 4-5 ohms would indicate primary winding wire.
0 resistance would indicate system earth wire.

[Magua]

The colour coding on your new one could be difficult to decide upon.
Can you email the supplier?

I guess I'll have to, damn it. Out of curiosity, what would happen if it was wired up backwards?

[tri boy]

Probably still work, as it is just a winding of copper around a iron base to produce an electric field. Might fail prematurely though.
Try the resistance check first.

[Magua]

Try the resistance check first.

Is that for the new coil?

[xwhatsit]

Do they have polarity? The ignition coil on both my RS and the C50 just has one wire, and it gets earthed through the bolt hole. It's obvious to tell which is the spark plug side, there's no wires there.

So why two wires? Is it an earth return or is it a coil for both cylinders?

[Magua]

Do they have polarity? The ignition coil on both my RS and the C50 just has one wire, and it gets earthed through the bolt hole. It's obvious to tell which is the spark plug side, there's no wires there.

So why two wires? Is it an earth return or is it a coil for both cylinders?

I really have no idea, electrics confuse the hell out of me. Mr David Silver should have included a simple diagram :@

Is that for the new coil?

I'm getting no measurements, I'll attach it to the bike.

[tri boy]

Is that for the new coil?

Yep
10chars

[Magua]

Yep
10chars

No reading, tried all the different resistance levels. There's some sort of coating on the base, scratched a bit away, no difference. I take it you mean to measure between these points? Terrible photo, terrible camera _b

[tri boy]

My useless attempt to pass info on is only making it more confusing for you.
Sorry about that.
Probably easier to email the suppliers.

[Magua]

Lol, thanks anyway.

[The Pastor]

No reading, tried all the different resistance levels. There's some sort of coating on the base, scratched a bit away, no difference. I take it you mean to measure between these points? Terrible photo, terrible camera _b

another mag speical photograph.

[Magua]

"The BLACK-with-WHITE is (+), goes to the IGN circuit (power). The other goes to the points."

I got that from another forum. Though, I don't have points :P

Both wires run to the CDI, the green ones appears to split into two after the CDI, one running to the altenator and the other to the ignition. The Yellow passes through the CDI before splitting into three wires and running to the altenator.

On that basis I'd assume it's black with white (+) to the green?

I'm still waiting to hear back from Davidsilver.