I have Trek 2300 with triple Ultegra group and Pinarello with compact Most (Pinarello) and 105 front and rear changers. The Trek has far more miles on it than the Pinarello, but it always feels and sounds much smoother and quieter. No, it's not a question of gear adjustment, nor lubrication but it seems to be the way the chain runs over the cogs etc. I love both bikes, but there is certainly a difference in "smoothness." Is this an alignment problem, a chain problem or a groupset problem or all three?