My '73 850 has been running lean at 1/2 to 3/4 throttle, so when I removed the fuel tank to access the tops of the carbs, I found there was a hole siliconed shut on each of the mixing chamber tops. I removed the tops, and there was no air-slide, or air-slide spring. There is no choke control on the bike, so I assume this mod was all part of the choke removal. Anyway, I did find that needle clips were set on the top setting of each needle. I reset the clips at the middle setting, and will test the bike on the highway once the weather improves. I went through both carbs, found they were very clean. I had posted earlier that the left header pipe had turned black at the first bend after a 1/2 hour ride, and thought it could be a carb issue, but now perhaps it's an ignition problem.
I will switch the sparkplug wires around left-to-right as part of my test ride.
I will switch the sparkplug wires around left-to-right as part of my test ride.