Another TD 20 idling question

[Fastwin18]

So I’ve fixed the leak along the exhaust cover.

It starts, runs (reasonably) smooth at high speed but simply won’t idle down. As soon as I move the throttle below the start position (see picture below) it starts sneezing and dies. Starting after that is difficult, unless throttle is move to much higher position.

Some background information:

• Motor has new rings and head gasket, compression of lower cylinder is 67 lbs, upper cylinder 70 lbs. Not very high numbers, I know, but it should idle down with compression like this right?
• Carb has been thoroughly cleaned
• Check valve works properly in one way
• Good spark on both coils
• Motor does not start very easy, but as said runs good at high speed
• High speed needle needs to be out 1 and a halve turn to run well, seems more than the proposed 3/4 turn
• Low speed needle is set to 5/8 turn out

My gut feeling says it’s starving of fuel, but I can’t quite put my finger on what’s wrong. Any suggestions would be appreciated.

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