Took a scooter in trade, doesn't idle

[johnwohl]

I took what I think is a Jonway Madness in trade for a debt and I'm having some difficulties getting it running. I've tuned EFI in cars for years but never messed with carbs.

This is what I know is on the bike from receipts;

high performance variator w/ 5 gram slider weights
performance exhuast system
performance cdi
performance coil
iridium plug
18mm carb w/ pod filter, #88 jet
performace clutch assembly w/ yellow torque and clutch springs
#38 pilot jet


I can't get it to start without a handful of throttle. The idle speed adjustment doesn't go that far. With me keeping the throttle open about 1/3 of the way it starts, increases rpms steadily for about 3 seconds, looses rpm, and unless I give it gas, dies.

I have the idle mixture screw set at 1 and 1/2 turns out but it doesn't seem to matter much unless i have it full lean or rich.

Here is a picture of the set up.

Looks like the vac port from the intake manifold goes to the fuel valve and the higher port on the carb.

The fuel fume vent thingy goes into the filter, as well as the vent on the valve cover.

The fuel line goes to the middle port on the carb.

Nothing is attached to the bottom port (the drain I think)