Has anyone used these coils?

[Brocky2]

I measured the primary resistance at 4.7 ohms.
I can’t work out how to share the actual link but copy and paste this into eBay and you’ll get it.
Ignition Coil x2 Honda CB400 CB500 CB550 CB750 GL1000 - 90mm 12V Points

[deltarider]

[...]
Is the primary resistance quoted?
A link to the actual item would help.

This ^ and is it a known brand? Advice in general: If no brand and made in China, abstain from ordering.

[McCabe-Thiele (Ted)]

Looks like these then. branded as SMP made for the seller in Taiwan?

.https://www.ebay.co.uk/sch/i.html?_from=R40&_nkw=Ignition+Coil+x2+Honda+CB400+CB500+CB550+CB750+GL1000+-+90mm+12V+Points&_sacat=0

[beardylondon]

Received these, both appear genuine and boxes too, both with unpainted NGK logo

[deltarider]

They are the same I have. Tip: use a little vaseline, silicone oil or similar inside the upper sealing rubber before you screw the HT wire on. That rubber seal is a bit tight and could therefore resist slightly and give you the feeling you are already there, when in fact you're not. Then you would have a bad connection.

[beardylondon]

Cheers!

[beardylondon]

Hi All

So I am starting to get my head round fitting the new coils....

As per photos below, the original wiring is coloured blue and black/white and yellow black/white the other side.

The new ones, as per bottom photo, the wires are solid red and white, so my question is, which way round do the wires go?

thanks in advance!

[McCabe-Thiele (Ted)]

Are the red and white wires shown the ones on your new coil as they look very long?
If they are then look at polarity markings on the coils themselves they should be marked +ve & -ve.
As the points earth the LT side of the circuit you need to ensure that the polarity matches.
So the negative side goes to yellow or blue for the respective coils. I would consider making up wires of the correct colour.

[beardylondon]

Yes, red and white wires are o new coil and yes they are supplied overly long.

Thanks for the tip!

[deltarider]

Generic coils often do not have the wires right; not only that the colors don't match, but also the connectors have the gender mixed up: females where they should be male and vice versa. Your choice.

[McCabe-Thiele (Ted)]

Yes, red and white wires are o new coil and yes they are supplied overly long.

Thanks for the tip!

FWIW my Hendler coils were wired for positive earth so I had to switch them to negative earth - this caused clearance issues  in the mounting position so I had to ensure the spade terminals did not touch the frame on the inside edge.

The Devil is in the detail when fitting aftermarket options.

[beardylondon]

thanks.

can you remember if the red was positive? when you switched, do you mean you put the red on the white terminal and white on the red terminal?

I've messaged who I purchased them from.

but how can I can test which terminal is which?

Yes, red and white wires are o new coil and yes they are supplied overly long.

Thanks for the tip!

FWIW my Hendler coils were wired for positive earth so I had to switch them to negative earth - this caused clearance issues  in the mounting position so I had to ensure the spade terminals did not touch the frame on the inside edge.

The Devil is in the detail when fitting aftermarket options.

[McCabe-Thiele (Ted)]

My black Hendler coils are white coloured at the ends where they are sealed and the terminals fit.
There was a black + sign on the positive side moulded into the white ends.
If your coils have no markings on the body at all then I would guess the red connections are most likely positive.

If the coils are connected the wrong way round the bike will run but the HT spark will be reversed so instead of jumping from the centre spark plug tip to earth the spark path is reversed. Not sure what difference this makes in the long term as I know nowt about that sort of theory. I have read that electron flow is not the way most folk think i.e. +ve to -ve but is the reverse.

Folks here will know about the Electronics side of things.