Ok,
so last winter i picked up a 72' cb350 off craigslist for $100. It had been stored out side for who knows how long, cleaned her up, rebuilt the carbs, cleaned out the gas tank, redid the fuel lines and did a tuneup. Ran great, sold it to a friend then it started running on only the right cylinder so checked it again nothing really out of sorts. Thought the coils might be going so i replaced with jcwit generics, plug wires, boots, condensers. ran great, then it seems about every 50 or so miles the left cylinder quits. got it to a guy with far more experience and he went through it and did some minor tweaking but couldn't find one single thing to cause the issue. my initial thought is points because as i ride i get back firing type sputter that corresponds with slight surges in power and it leads me to think the spark is fuzzy on that side. any thoughts?