TOPIC: No start puzzle

Don: Yes, the starter spins the engine just fine, hot or cold. Further, it bump started instantly every time, as soon as I let the clutch out in second.

Ralph: I don't see how reduced voltage while the starter is engaged could affect the spark. The ignition system on the first generation KLRs is powered by an "exciter coil" on the stator which is isolated from the rest of the electrical system.

It's a mystery.

Sometimes I miss kick starters.

Frank

This is so strange and doesn't make any sense to me logically BUT it worked so I must be missing something. I had a few other ideas when reading the original post but none of them fit after reading the solution! I'm stumped to the "why" and happy it resolved your hot start problem but I'd sure like to understand why!!

Yeah, Don, I agree it doesn't make sense. I have a nagging suspicion that this is an intermittent problem, and that going away with the new plug was coincidental. Time will tell.

Frank

Frank Beatrous wrote:
Hopefully (for whatever reason) the problem is solved but I suspect you maybe right that the issue may surface again Please post if the problem returns and then we can try some other steps to get it fixed.

My no start problem went away for a few days after replacing the plug, but now it's back.

The issue is that the bike sometimes is hard to start or won't start at all using the electric starter. This has me stumped.

Here's what I know.

1. It only happens when the engine is warm. Cold starts are never a problem.
2. The starter spins the engine normally, hot or cold.
3. The issue is intermittent.
4. It always bump starts easily, even when it won't start with the electric starter.
5. The bike runs fine once started.

I have verified the presence of spark during a no start condition by spinning the engine with the starter with a timing light pickup on the spark plug wire. I cannot rule out the possibility of a weak spark while using the electric starter, but the mechanism for this would be weird, since the ignition system is electrically isolated from the rest of the electrical system. On the other hand, any other explanation I can come up with seems inconsistent with easy bump starting.

Any thoughts?

Frank

Boy, before you replaced the plug, I was leaning toward a pick up coil.
It still could be. As soon as you said it only happens when warm, that's the first thing that came to mind.
Just because you get a spark, you can't know for sure of it's strength.
Wish I could be more helpful, but you have a real tough one there.
Let us know if you find an answer.