Hi, I have a 2011 DHZ DPRO 160cc (pitsterpro z160ho engine) And I'm having a similar problem...I'm using a mineral based SHELL engine oil. What happens is I start up the bike in Neutral, hold in the clutch and click up to 1st. As soon as i do this the bike stalls. So I'm guessing the clutch just isnt engaging which would mean even when holding in the clutch in first gear the bike stals because the clutch isnt really being engaged. The bike is only about 3 weeks old and has been ridden for about 2 hours tops until the clutch ****ed up. When the engine is not running and the bike is in first the bike doesnt roll. When I hold the clutch in, in 1st the bike rolls but I have to push it really, really hard! I have tried adjusting the cable at the lever and at the engine but i think it is an internal problem? Can someone please help me with this problem?