Townmate T80 cold idling problem

Hello hello,

As I mentioned in my last question, I've got an old T80 which I'm fettling back onto the road at the moment. I hope you don't mind me clogging up the board with a few questions! This question is about (lack of) idling when cold.

Happily, the bike starts quite easily, even from dead cold.

When the engine is still cold it runs and revs fine, but cuts out as soon as it drops to idle. Pulling on the choke makes it worse. Screwing what I believe to be the throttle stop (X-head screw the left of the carb) a few turns inwards helps a lot though, and it will idle happily while cold.

However! Once the engine has warmed up, having the throttle stop adjusted as above naturally causes it to run far to fast with the throttle closed (making gear changes impossible), so the screw must be let back out. This done, it idles sweetly again.

The bike's principle rider (my girlfriend) is new to operating machinery and is finding it very difficult to get the hang of riding it cold while this problem persists, especially shifting down to neutral as she comes to a stop without stalling.

Incidentally, when the bike is warm, and the throttle stop set in the 'correct' position, it runs and revs fine, but tends to hesitate (as if considering stalling) when the throttle is rolled on from idle. I don't find this annoying, but I mention this in case it is a further symptom of the same problem.

Anyway, I'm sure there is a perfectly simple adjustment I need to make somewhere to solve these cold-running issues. Anyone know what it might be? The carb has been recently cleaned

Thanks again for your help,
M-S

This problem has already been discussed on this thread which you may find helpful https://yamahatownmatet80.forumotion.co.uk/t296-won-t-idle-when-cold