Changing carburetors

Thought I'd sorted out the boys 125. Took the plug out - black,wet & sooty, so must be running rich?

Warmed the engine up after struggling to get it started - nearly flattened the battery so resorted to the kick start. Wouldn't fire with the choke on but revved like a bastrad without it and died when I tried to hold it on with the choke.

Tried the colortune plug and got the Bunsen burner blue colour almost straight away. Revved it up and got the blue to yellow back to blue as it climbed up then dropped when I released the throttle. So seems okay ( that's what the colortune booklet says it should do)

But, I still think there's something wrong with the carb. I'm thinking of changing it for a proper honda cg125 carb the bikes a lexmoto Arizona so the engines a cg clone. Does anyone have any I info on them? Is it likely to be a straight swap or am I opening up a new worm can?

I'm not sure but most likely that carb on Arizona will have 2 throttle cables going there, is not a problem you just have to remove that 2nd cable where they split or fit Honda throttle cable, someone did mention about improvement once they fitted original Honda cg carb to there lexmoto, mine lexmoto carb improved once I replaced main jet from 95 to 100, this wasn't done for performance gains just runs lot better.

Might try a total strip down, clean and change the jet like you suggest

A black wet and sooty plug can indicate a poor spark. Why did the bike need sorting in the first place ? If there are no modifications to the air box or exhaust then the carb should be ok. Carbs don't break and there's not a lot to wear out so I would try a strip down paying particular attention to the float valve assembly. Look for the tiniest specks of dirt behind the float valve needle . Also check out the HT lead and plug cap.

Something I hadn't thought of. The it cab!e does look like its seen better days