Had similar symptoms with mine, ran like a dog at low revs and fine once warmed right up or when i was giving it the beans. wiser men than me have informed me that the pilot jets are blocked in my carbs and they need sorting. Apparently its a bit of a pro job and you need to use a sonic cleaning device to unblock the jets. On the other hand, my mate said that he once made a carb cleaning device from a tupperware box and an orbital sander....


Me, I've bought some second hand carbs from e-bay which i am going to fit when the weather gets a bit warmer. £70