I have a dead coil, so I replaced both with https://www.munichmotorcycles.com.au/product/ignition-coil-kit-aftermarket-new-style/ which I believe is out of a Ford Focus. Comes with HT leads and instructions on how to wire.

Seemed a pretty simple job, even for someone of my meager skills. But since the change I haven't been able to get any spark. Power is getting to the coil ok, but the plugs aren't sparking at all. It was running (very badly) prior to starting the job.

It's got me stumped, there doesn't seem that much that could go wrong. Starter motor is cranking away happily and fuel pump is doing it's thing. I have been through all trouble shooting flow charts and nothing stands out. The only thing I can think is that the ignition module has chosen this exact moment to dies, but that seems unlikely. Or maybe the relay died?

Suggestions?

First thing for me refit the good coil check for spark. That way you have a starting point for a solution.if the old coil works, new coils not suitable. if old coil not work check wiring. KISS is always best.

Another possibility (I guess Munich motorcycles wouldn't sell them for bricks if they weren't suitable) You could ask how many of these new ones they've sold and ask for help.

So if the coils are good but there's no output, there's something wrong with the inputs. How have you wired them up? Can you post a photo of the instructions?

They are suitable for all the motronic systems with the ignition amplifier.....as they are 0.5 ohm primary coils 

Seen a few use these on k100 cafe builds 

Not my first choise  for a happy ignition system on the old ones
 In any case sounds like a really bad earth on the ignition computer.

moriarti wrote:First thing for me refit the good coil check for spark. That way you have a starting point for a solution.if the old coil works, new coils not suitable. if old coil not work check wiring. KISS is always best.

Yeah I was thinking of heading down this path, but was dreading redoing all the connectors. But I only need to use the one good coil and 1 good lead I have which is much easier. Great tip, much less an intimidating job.

daveyson wrote:Another possibility (I guess Munich motorcycles wouldn't sell them for bricks if they weren't suitable) You could ask how many of these new ones they've sold and ask for help.

So if the coils are good but there's no output, there's something wrong with the inputs. How have you wired them up? Can you post a photo of the instructions?

Yeah, I nearly rang them yesterday and if I don't get anywhere I will definitely give them a call.

Wiring is very simple, just the 3 wires and you don't use the ground. I don't have a picture, but this is the set-up (they provide a connector).

charlie99 wrote:They are suitable for all the motronic systems with the ignition amplifier.....as they are 0.5 ohm primary coils 

Seen a few use these on k100 cafe builds 

Not my first choise  for a happy ignition system on the old ones
 In any case sounds like a really bad earth on the ignition computer.

Hard to get genuine coils these days and then no guarantee they won't have the same issue after a couple of months. 

I will double check the earth on the Ignition module, but I am pretty sure I cleaned that a few weeks ago.

I'd be considering a refund, especially after reading Charlie's post.

Your coils have black plug terminals I think, they're known for failing. 1986 and on are okay. Where abouts in Melbourne are you?

daveyson wrote:I'd be considering a refund, especially after reading Charlie's post.

Your coils have black plug terminals I think, they're known for failing. 1986 and on are okay. Where abouts in Melbourne are you?

I think they should be working fine and should be compatible, wondering if its maybe a plug issue.

The bike is in Pakenham (and sometimes I am too ).

What's the part number and brand?

There was a recent thread with coil's that look like yours, which makes me think that when you get the problem sorted, the next problem might be that the tacho is out of whack.

charlie99 wrote:

Seen a few use these on k100 cafe builds 

This is clearly not a proof of quality.
Are you sure it's the coil the problem?
They seldom fail, the most common issues about ignition are cause by the hall effect sensor aging and/or a dumb wiring "simplified" to insert crappy magic boxes.

daveyson wrote:What's the part number and brand?

There was a recent thread with coil's that look like yours, which makes me think that when you get the problem sorted, the next problem might be that the tacho is out of whack.

The part number of the new one? I don't know, but I think it comes out of a Ford Focus. 

I read the other thread and he has implemented a similar solution. I wondered with the tacho issue if that was because there are two wires for cylinders 1 + 4. Unfortunately I haven't got far enough to experience his issue.

jbt wrote:

charlie99 wrote:

Seen a few use these on k100 cafe builds 

This is clearly not a proof of quality.
Are you sure it's the coil the problem?
They seldom fail, the most common issues about ignition are cause by the hall effect sensor aging and/or a dumb wiring "simplified"  to insert crappy magic boxes.

I know 1 of the original coils had died and 3 of the original HT leads are operating out of spec probably due to age. 

I don't know if the new coil is faulty, the testing I have done suggests it is ok. I am concerned something like the hall effect sensor has chosen this exact moment to fail.