Bike misses- Ignition or Carbs??

Bike was running great. Put in new plugs this year, cleaned the carbs ridden couple hundred miles and everything was great.

Took off to work and after about a mile or 2 it started running odd, weird vibrations and such, popping from exhaust slowing down after a high RPM run. Will only rev to 6K.

Got to work and #4 pipe is barely warm and the others are blistering hot. 18 mile run 16 highway, last 2 city.

Nursed it home after work. #4 plug is black other 3 still look almost new.

Started it up....got it warm, pulled #4 wire, no change, if any, in the way it ran. Ditto for #1 but if i pull #'s 2 or 3 it will barely start let alone run.

I get spark at all 4 cylinders but 1 and 4 are weaker looking.

At this point i am leaning towards a weak coil for 1 and 4 and have one coming via ebay I picked up on the cheap, but I was thinking that plug #1 would have been black like #4.

Anyone else think I am on the right track? I really don't want to have to go through the carbs again.

 

I wouldn't tear into anything just yet. Since it started after a refuel I would suspect bad gas. Half a can of Seafoam will help by mixing with the water or bad gas and letting it burn. IF spark is to blame I would check the #4 plug cap for proper resistance. Wouldn't hurt to exchange the caps and see if the problem moves.

 

Do you have an Inline Gas Filter protecting the Carbs from foreign matter in the fuel?

Do you have a Fuse Panel upgrade?

Run a test on the Coils by swapping the Coil Plug-ins to the Wiring harness and see if the trouble follows the swap.

If you get a good spark on 4 and 3 acts-up after swapping the Plug-in's ... THEN you can suspect the Coils.

 

Yes to the filter and no to the fuse panel upgrade. I keep putting the latter off.

So i can switch the harnesses on the coils and it will still be in time?

I thought about that but was afraid to break anything else. Seca ressurections 2008 has been anything but fun this time around.

I already cut the pick up coil wires putting a new gasket on the shift cover and had to resplice those. I wondered if that might be the problem but my splicing job still holds, i figured too if it wasn't i wouldn't get any signal at the coils not just weak.

I will try to swap and see what that does. Thanks!