So I've got a Vento Triton Li (2-stroke) that for the first ~300miles ran perfectly. Lately, however, it's been giving me problems. Suddenly it would misfire/stumble at higher RPM then die when the RPM wound down. However, it starts right back up after. It's not having problems getting fuel, good spark, the only thing I can think of is that the oil pump died. If I pull the oil line off the carb and turn over the engine (no plug), oil should start coming out the line eventually, right?

Any help anyone can give would be appreciated.