Ignition coil question, EC300, m.y. 2009
 

I have a very weak spark, and the engine is not starting. Prior to this happening,

- the engine sounded really rough and vibrated quite a bit
- right before stalling, it would not idle, but remained running a few seconds with applying the throttle - then it died
- during the previous two times I had been riding, the odometer would go nuts and show only 8888's when revs went above 7.000 rpm. I am not sure if this is related to the present problem

So, I am not 100% sure if I have:

- a malfunction in voltage regulator
- an issue with the carb
- an issue with the ignition coil

Anyway, the spark is very weak.

I have checked that the plug cap gives 5 kOhm.

When I measure the coil, I get 6.2 kOhm between the spark plug connector (2nd for the bottom) and the thin lead which goes inside the coil housing (1st form the bottom).

I also get the exact same resistance between the plug connector and the thin terminal (1st from the top).

Resistance between the thin connector (top-most in the image) and the thin lead (bottom) is 0.3 Ohm

Ok using your list:

Voltage regulator is not part of ignition cct. If you have a std odo, well done! They rarely remain working. You might consider chasing earth connections for it once bike is running.

Carb, spray some engine start with filter removed down open airbox. Brake clean usually works if you don't have engine start spray. Then quickly kick.

With a new plug, another one, try again.

I'd be reasonable confident your stator was failing. Ktm aftermarket one will work. They don't last forever but 10+ years is ok.

Finally your meter is a great tool. But it has limitations. Serious ones for bike electrics. Things can measure fine but fail under load.

If the stator is gone.

My bike is 'Racing', which is supposed to have a lower output stator and a light-weight flywheel.

Possibly need to have the stator rewound; once I'm sure that it's toast.

Lower output would be a 2K2. I would think they are available. No harm in installing a 2K3 and larger flywheel if necessary. Only one of the windings actually powers the CDI.

Geez that's dramatic! I'd day if your stator is gone , you've been taken to dinner and a movie but haven't gone inside for a coffee.:p

Sent my 2k3 for rewind but guy said way epoxied made to difficult.

But there are bound to be 2k2 options in aftermarket.

Literally 1 min of search

https://www.rickystator.com/product/...ator-2006-2015

I got a UK made electrix world and it has proved good.

I'd be surprised if the 'Racing' model on an 09 actually even used a 2K2.

My 2010 Euro Racing had a 2K3
My 2013 Racing had a 2K3

Pretty easy to tell.

How can one tell is spark is weak or strong?

I'd start with a new plug, some fresh fuel, and a clean carb. If she still doesn't fire.. can try cleaning the earth connections and trimming back of a bit of the HT lead and reattaching the plug cap.

Voltage regulator shouldn't stop the bike running. You'll be able to probe to check voltage on the 12VAC circuit once she's running again.

I guess it's easy to tell the stators from each other - if you know the differences. Possibly you can see it from the connectors. Maybe it requires the flywheel removed. In that case, you need to know what kind of a puller is needed and then source it. Once you know exactly what you are looking for, you can find it online in a minute - give or take.

It is easy to tell a weak spark from a strong one. A good healthy spark is easily visible in broad daylight. A weak can be seen only in dimmer illumination.

A 2K2 smaller stator will exit the flywheel cover at the 10 oclock position. If not there'll be a rubber grommet/seal in the cases and the 2K3 will exit around the 1 oclock position.

If you have a 2K3...

http://www.gasgasrider.org/forum/sho...ghlight=stator

Did replace the plug cap, which improved the situation a little. The spark turned from yellow to blue with some increase in spark intensity. But still not visible in daylight. I managed to start the engine for a split second; something which happened once before. After that, no luck whatsoever even with pilot spray.

The concepts of 2k2, 2k3 helped me to direct searching in the right direction. I assume that one can distinguish them right from the flywheel O.D. Mine is 106 mm.

Managed to loan a puller (27x1mm, left-handed), and the internals resemble those of 2k3. Must say that it would have been a no-go without any. I needed a half a meter bar and had to rest the other wrench against a foot peg to be able to release the flywheel.

Resistances are within specs - but apparently an internally shorted coil cannot be detected by resistance.