Seafoam causing carb problem??

Sounds like coils.
Steve

tri650 wrote: Ran it again tonight. Same story - 6 miles and then started to sputter. Pulled over and opened gas tank cap and then closed and started. Same story. I went a little further and then pulled over again and opened gas cap to where it was slightly open but wouldn't open all the way. Same story. By the time I got home it was barely running and died when I pulled into the driveway.

Pulled the plugs 2-4 looked normal - tan in color. Plug #1 looked totally clean - like it had not been used. Mean anything?

A clean white plug would indicate too lean?...not enough fuel in that cylinder?...hmmm ........................Mike

..."If your spark plug is white in color or appears blistered, that means something is making the plug run too hot. Check for problems in your engine's cooling, a lean fuel mixture or incorrect ignition timing"....

Vroom-vroom!

www.verrill.com/moto/sellingguide/sparkplugs/plugcolorchart.htm .....................................Mike

Vroom-vroom!

The #1 plug looks totally clean - basically bare metal. Doesn't match anything on the chart. Plugs 2, 3, 4 match the one that is normal.

I have not checked the coils. Would they tend to stop functioning properly if they get hot?

That's one of the symptoms of them going bad.Switch coil leads and HT wires and see what happens.
Steve

Thanks - I will check that out. I also did a search on testing your coils and found a few youtube video's using a multi-meter.

That won't tell you how they're doing under load or when they get hot.
Steve

swest wrote: That won't tell you how they're doing under load or when they get hot.
Steve

Agree but it could show up a bad plug cap. cheap and easy to fix.

I had a 1980 750LTD with original coils. The thing ran great for the first 5 miles, then it would just get GUTLESS. I could get the RPMS up in neutral if I worked the throttle but it had no power - but it ran somewhat balanced, which was odd.

I tested the coils and caps cold, tested fine. I replaced the wires and caps first (I'm cheap). Still the same thing, once warmed up it ran like crap. I borrowed a coil from a local shop that I'm friends with the owner. Replaced one coil, same thing....replaced the other with the loaner and it was fixed. So the coil tested just fine, had no cracks or anything, but once it got warm and stressed out it gave up.

I replaced both coils on my sons 81 KZ1000 last summer. Similar problem. We were on a 200 mile ride and the last 60 miles or so it just popped and missed but he could go the speed limit. Put a set I had off of a CB900 on it's running strong. It was still worth checking wires and caps.

I am planning to run through the usual tests cold to eliminate caps and wires. If they test OK I will probably try and find a used coil that I can substitute.

How old are your coils?
Steve