What I was really hoping was for the problem to be outside the engine. Fix that and get it running, however badly, then open her up for a valve check, etc.
Pretty sure the carb is screwed beyond cleaning, the choke cable is loose at the point it goes into the carb. But that is down the road. Need spark first.

 

Do you have the manual for it? what year is it?

 

I would get a wiring diagram to help you troubleshoot. The 250 wiring diagram I have does not have a condensor with the elec ignition system. Are you sure it is a condensor?
1. check battery is charged
2. check spark when starter is engaged (how are you testing this?)
If you done those and no spark, you should be able to test the coil with the battery & VOM. It may be the ignition module.

Don't believe anything that the seller tells you, unless he is your friend.

 

It doesn't have a starter or battery, this is a 93 KLX650R, kick start only.
I checked for spark by holding the plug against the engine and frame, while kicking it over. Not very scientific, but in the dark I should be able to see a spark, even a faint one.
I know the seller might be full of crap, but the engine "seems" fine. It has compression, no strange noises when kicking it over, and is getting air and fuel (I used some starter fluid too, no joy), which brings me back to spark.
My diagnosis technique for fixing things starts with those 3 things. After that I need help or a manual.
I should get a new plug, just to make sure it isn't that.

 

So does it have points or a ECU?
It could be a bad plug or condensor part (if that is tied to the spark system), that would be the most logical problem.
If that is good, I suspect the coil or ECU.

 

For reference... condenser and capacitor are one in the same.

 

I see from the generator diagram that the condenser appears to be at the connector at the voltage regulator.

 

I don't know why every wrench calls it a condensor, that is really only good for moonshine. If the capacitor is on the voltage regulator, I don't see it causing a problem if you have points.... other than the magneto/alternator may not make any voltage for the ignition system without it.

Hook a VOM set to voltage (probably the highest range) to the spark plug wire an kick it over... if it jumps, it is the plug. If it don't just keep moving up the system till you get to the mag/alternator (once past the coil, reset the range to 12 or 24V).

Leave the plug out or your right leg is going to get a lot bigger than your left.

 

Which I think means it's there for electrical noise suppression.

 

In older ignition systems which used points and condensers (capacitors)... the capacitor was a storage bank for the collapsing field from the transformer that occurred as the points opened... I know more of old systems than new ones so I have no idea its purpose or true intent in modern engines... though it seems the new systems found ways to eliminate points, but it seems you would still need a capacitor for the energy storage.

p.s. I haven't read the post thoroughly so forgive repeat or un-needed info. :-)