Gilera Runner Vx Cuts out when I rev?

I have a Gilera Runner Vx 125, It was running fine when I last ride it. I Havn't been on it for about 6 weeks now.
Trying to start it was a pain (this is usual when cold), I found out that if i pull the throttle cable (next to the butterfly connected to carb) directly about 3 times, the bike will start first time. Once the bike is warm I can easily start it with just the electric start.

However my problem isn't to do with starting it, after I got my bike started today I tried to give it a little run and as soon as the wheels start moving the bike cuts out. I left the bike running on idle for 10minutes and tried again, but still failed. I put the bike on stand and revved it as much as I could without it cutting out, I did this for about 5minutes and tried but it still failed.

Any ideas what this could be?

I've many ideas to what it may be, I believe it could be;
Just too cold?
Fuel pump?
Bad mixture?
Or possibly the clutch?

I've had this probelm once before, but it only cut out the once and then when started again it was fine. This was many months ago.

All help is grateful. Thanks