I live in Northern Ireland. Recently purchased my Yamaha fzx 750 from a reputable dealer in London. They told me that prior to delivery the bike would be fully checked over before it would be delivered. They told me they had to clean the carburettors as the bike had been sitting up for a while. They said they steeped the carbs for two days, replaced a needle and that it was running fine. When the courier delivered the bike I took it out for first run and the bike is not running fine. It is spluttering when the throttle is opened and will splutter and then accelerate very slowly. Local Yamaha dealer said it will cost between £300 and £400 to strip carbs down and see what the problem is. Any information would be much appreciated. Thanks.