Modern Vespa

So after having a problem with engine dying at stops (https://modernvespa.com/forum/topic127520) i drained, flushed and cleaned the gas tank, installed a new 'high flow' fuel tap. Also replaced the very war torn (getting a bit loose) barrel studs, and lapped and re-torqued the head. Now getting a compression reading of 107psi (up from 100), and the scooter is all dandy when idling at stops now. But.... another issue has reared it's head. The scooter runs well, idles at stops, pulls away well from stops, and after a good run out the spark plug is a pretty good caramel brown color. But during each run out the scooter will splutter and die on 1 or 2 occasions when slowing down and running at low revs, e.g when shifting to 1st gear and lazilly making a u-turn. When this happens it's real job to kickstart again. Best bet is to coast down a hill and jumpstart the engine. Once the engine is started though, it runs strong again and will probably not die again for the rest of the run.

I'm curious what this sounds like to the more experienced ppl here. As far as i know the timing is good, Carb is good, spark plugs are good, coil is good, HT lead good, head is good, fuel tap is good, points are good.

Cheers

For anyone interested; i took the float and float needle out of the brand new Spaco carb, and replaced them with the old ones from the warped Dellorto carb. It seems that solved the problem; massive improvement in running at lowest revs just above idle.

Not sure why the Dellorto float helped in this, but i did notice the slight difference in shape between the 2 float needles.