My son got recently a Dahon Vitesse D7HG from a LBS. Overall he is very happy with it and it look really good after removing fenders and rack.
The main issue he has with the bike is that the seat post slides down a inch or two every few miles (he is a big guy).
The seat post does not seem to be lubricated and we tried to tighten the QR as much as possible.
Any suggestion how to secure the seat post?