Hi I have the same problem but think its due to being injection. I am going to fit a pair of race pipes, k and n filter, then a power commander, it aint cheap but will sound and run a lot better from the many mechanics i have spoken to about this problem. Also as its a twin it shows even more when in traffik, pity i cant afford to do it till next month cos im riding to africa on it in two weeks!!!!! if you hear of an alternative, im all ears!!