Hi, I am looking for a reasonably priced 24 inch bike for a girl and I want the lightest bike for her, to last a few years (she's 8). Narrowing it down to the Scott Roxter and the Momsen JR100 (because they are available on this site second hand), but the Scott seems to be 11kgs and the Momsen is 13.8? Significant weight difference I think, but is it real?