Originally Posted by
berlinonaut
It is possible to retrofit the new standard wheels to older bikes. No problem on the rear frame. Those with a rack should be aware that the rack changed in 2016, too, using M6 bolts for the wheels instead of M5 before. It is however possible to fit the new wheels to the old rack by making use of some of the parts of the original wheels (or by drilling a bigger hole).
If just swapping some little roller wheels might void the warranty, the owner/individual consumer drilling out a hole has got to void the warranty!
I see some Brompton dealers are advertising a complete rack/wheel kit that upgrades to the new design, but state there's no warranty unless all the parts are installed by a professional bicycle mechanic.