Motofino Issues :/

[99owned]

Hey guys I've got a motofino MF50QT-6 4 stroke scoot.

As soon as I got it, I changed the oil, (Was black and filled to the BRIM.)
New Spark Plug
Cleaned carb (was already clean, just went in and did it anyway)
Also adjusted the valves to .004

It will idle all day long, Take it out on the road, it bogs with throttle, unless you keep it at like 1/4 or so.
Then if you let go of that 1/4 throttle, it kind of sticks.
Almost like it has a vacuum leak or something.


Any ideas? I've got some exhaust nuts on the way now, since the exhaust valve was taking a beating with a huge leak like that.