1) they don't leave much ground clearance for swapped out handlebars with front extensions like mine (when the bike is folded and the handlebars are near the ground), and
2) they're kinda small so they don't roll great on my office carpet.
But, the Brompton folks were very smart in designing it cuz the rear triangle can be very costly to fix if it gets bent, so they designed the roller wheels to be more fragile than the rear triangle. Just in case the bike is dropped when folded, you can count on the wheels to break before the frame bends. Kind of like a crumple zone. The wheels are cheap and replaceable anyway.
But I figured I could use the extra clearance and rollability, AND the bigger risk of any kind of frame damage is probably at the end of the triangle closer to the seat. So why not keep THOSE wheels and swap out the ones right at the end of the bike? That way when the bike is folded I can "tow" it by turning the seat backwards and using it as a handle (like I always do when I get to the office) and the larger wheels wld be the one rolling on my office carpet. Perfect.
So that's what I did. Very happy now. Many thanks to my friend Nick who gave me his unwanted roller blade wheels which I think look awesome on my bike. :)
Also, most sites (like this one, which is an awesome cycling blog btw: http://unfoldandcycle.com/2012/02/22/brompton-upgrade-skate-wheels/) have suggested that you need longer screws than the ones the bike comes with though in order to keep the bungee cords tied on. But I discovered you don't! Because you can loop the end of the bungee, which used to be attached to the same screw as the roller wheel, around the rack instead. If you do that the screw is actually the perfect length to attach a roller blade wheel. Awesome! :D
