I have the cheapest Brompton made.An S- type, no fenders no nothing,single speed. I added a brooks B-17 and Ergon 2 grips and a stem extender and water bottle cage. On my scale it weights 22.5 lbs.with these installed. And i have weighed it at LBS and was same although i cant guarantee exact accuracy. From what i understand the titanium one which definately is not the cheapest will weigh about a pound less give or take,however soon as you add gears it goes up lots.