I have a '71 Honda CB350 that is new to me. I recently rebuilt the carbs and replaced the petcock and had it running pretty good for awhile. I saw your in depth answer here for a question about running lean or rich.
I replaced the plugs only two weeks ago. I pulled my new plugs and I saw that the right one was black - indicating that it runs rich (right?). The left plug looked ok (I think). I also saw that you mentioned that if it runs with choke open then that means it runs lean (right?). My problem that brought me to that thread was that I am not getting enough power when I am in the low gears. If I try to get into first nice and easy then the engine putters but gets going eventually. It works a lot better if I use a lot of gas to get through those first 2 gears. The bike was running ok, granted only with the choke open for about 100 miles but now has developed this problem.
What do you suggest?
Also, I live in Denver so is altitude an issue?
When I rebuilt the carbs I used the 105 main jet that I learned was stock. Should I change that to the 115 that was also sent with the kit for any reason?
Thank you so much for your time. I really appreciate it as I learn how to trouble shoot this bike hopefully I gain some wisdom through this process that I can one day pass on to someone else. Thank you.