Stella now missing- what's up?

[Anachronism]

Riding home last night, my Stella started to cut out and miss. It never stalled, but would momentarily lose power and then catch, like it was missing on every third fire.

The bike starts and idles perfectly fine. When cold, the bike runs normally for about 5 minutes, then the symptoms start.

I pulled the plug, it was not wet, light tan in color. Looked good, if maybe a LITTLE on the lean side.

Any common culprits that would cause this?

[bluezurich]

Could be a bad lead to the plug or mixture?

[Lovelandstella]

Riding home last night, my Stella started to cut out and miss. It never stalled, but would momentarily lose power and then catch, like it was missing on every third fire.

The bike starts and idles perfectly fine. When cold, the bike runs normally for about 5 minutes, then the symptoms start.

I pulled the plug, it was not wet, light tan in color. Looked good, if maybe a LITTLE on the lean side.

Any common culprits that would cause this?

ebay a "IN-LINE IGNITION SPARK PLUG TESTER ~ TROUBLE SHOOTER "
I hear they make dx'ing the problem a LOT easier!

[jmkjr72]

mine did the exact same thing look at your coil
ill bet you will find where the grounding strap gounds out to the frame of the coil you will see the soder joint cracked

[Anachronism]

I had it scheduled for the shop to fix my gas gauge, so they are looking at it.

I think it is ignition related, but I would think I would see a wetter plug. Maybe it is because it hasn't had time to foul.

I didn't see any thing amiss in the ignition system, but I didn't look terribly closely.

[crackhead]

I had exactly the same symptoms you described a few months back. Turned out to be a dirty carb. My original intake bellows had rotted allowing dirty engine bay air to enter and clog the carb. I took off the airbox cover and sprayed out the carb and jets. In the case of the carb I sprayed it out both while running and while not. Of course I replaced the bellows too. Took care of it.

Another possibility is the kill switch. They have a habit of shorting out and will cause similar symptoms. It sounds like your plug is normal enough that I wouldn't worry as much about that. Also, your coil tends to work or not work, with nothing in between. So I would not think that is the issue.

Good luck! Let us know how it works out.