Spark plug terminal nut. Check 'em!
When adjusting the air/mixture screw (while tuning the carbs) I noticed that one of the cilinders kept backfiring no matter how far in or out I turned the air/mixture screw.
I removed the spark plugs to check the color and then I noticed one of the terminal nuts was loose. It was nearly falling off.
Altough I tightened them with a set of pliers when I installed them, one had come loose in less then 50 miles.
I noticed the same problem when I bought the bike and renewed the spark plugs. Back then, both terminal nut were loose.
Apparently these things come loose very easy, no matter how tight they were during install.
Anyway, once I tightened the nut the engine wasn't backfiring anymore with the air/mixture screw set to 3 3/4 out (K&N, stock airbox, Dynojet 1, open Bos mufflers).
So have any of you guys experienced this same problem with the terminal nut coming loose? And if so; how did you fix it?
I winded a single strand of battery cable wire around the thread prior to installing the nut. Now the nut needed a lot more force to go on so I hope it stays in place.
I was also thinking about Loctite but I think Loctite isn't the best electricity conductor so I went with the fine copper wire.
1997 Ducati 900 SS Full Fairing