1975 Honda CB125S and 1981 CM200T


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Fuel is going directly into the carb currently and seems to flow fine. No tank or petcock currently to worry about. When assembling the float, I adjusted it to spec, 24mm I think. It was at 21mm before adjusting... way off.

I too was thinking the main jet may have an issue but I want to make sure the electrical system is in good shape before I break open the carb again.

Anybody know what the ohms should be on the coil?

Where do I test it’s voltage when running?

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Was the engine fully warmed up w choke fully open? (At idle it will take better than 10 minutes to get it good and warm). But I’m betting the main jet is clogged. It will idle just fine but goes super lean when you crack throttle. Or the choke wasn’t fully open and going rich cause it couldn’t get enough air.
By the way, thanks for all the tips and suggestions. I’m taking them all in even if I don’t directly respond. I really appreciate it.
Choke was open and I'll check the main jet sooner than later. In the video, the engine was not warm, but this weekend I let it get run for a good 10 or 15 minutes before adjusting the air screw to try to lean it out. The (new) spark plug was super black which is why I was thinking it was running rich, but maybe the idle was rich and when I cracked the throttle it went way lean. Once it was warm, I would barely touch the throttle and the engine would rev. If I was light on the throttle, it ran okay, heavy on the throttle and it would get very rough. Next time I get it re-assembled I'll record so you can hear it. Fingers crossed that adjusting the timing will help. I am suspicious of the electrical system as well.
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