Thanks for the reply, I have tried to richen the mixture but
Still no luck. Even when the hsn is at the fresh out the box position it still bogs at full throttle. Should I be able to go from standstill to full throttle and not have any problems or does the speed have to build up. I have a video of what happens when I do this which I will upload at some point, on iPhone at the mo so can't. I took the engine apart today and had a look but everything looks new still so hopefully no damage has been done.