There's almost no difference between the weight of the Brompton 2 speed and 1 speed. I own a Ti 2 speed and that second gear makes it large difference. I really don't know why anyone would buy a 1 speed just to save a few grams. Yesterday my wife climbed over a 1000 ft on a 2 speed Ti Brompton. I rode my steel 6 speed but she finished ahead of me.