[DaveO430]

it was the voltage regulator connector that was blown.
p.s. i don't speak a word of english, i use google translate. if I post inappropriate terms, take it out on him.

Glad you got that fixed, it will cause problems. Google did a good job on this last post anyway.

 

[claydbal_1590]

so, voltage drop caused one coil to spark weaker than the other?

 

[icechopper]

meanwhile there have been developments.
the different color of the spark plugs was due to an electrical problem.
for a few weeks the bike was no longer running well, as if it were running on 3 and a half cylinders.
it was the voltage regulator connector that was blown.
I have now set the idle screw to 3 turns and the popping problem has improved, but not completely resolved.
p.s. i don't speak a word of english, i use google translate. if I post inappropriate terms, take it out on him.

So the dark ones were the problem? Good find on the VR plug.

 

[Texaco]

So the dark ones were the problem? Good find on the VR plug.

due to the blown connector the spark was not optimal and the engine did not run well.
thinking it was a carburetion problem I made some wrong adjustments.

now i think i have solved it.