O.S. 0.3 vg tuning issues
 

I was wondering. If anybody can help.
I have a Hyper 7 with a O.S. vg 0.3 engine. Yep it goes. That is when I can get it to run right.
It goes ok for about 2 mins. AS soon as it gets some heat in it. It start to go flat at low rev's. This then leads to it cutting out. When it starts going flat. If you can get the revs up. It goes ok until you back off. Then the same issue. I have taken it back to factory settings Which to my knowledge. Is low speed. 1 1/2 turns in from level. High speed 2 1/2 turns. I also seem to have to have the idle open a fair way just to keep it running. I have alot of trouble starting. It at times seem it is lacking fuel. I have had it backfiring some times
This issue is doing my head in. Can someone please help