You can easily take out the pump off the post and save some weight if you don't need that pump.
There are also a lot of nice parts you can get cheaply via ebay from Hong Kong, for example, this Tuner saddle posts: http://www.ebay.com/itm/TURNER-Seatp...item3a7adbb9b9
These are even lighter: http://www.ebay.com/itm/2012-GUB-Sea...item51a2fcbe20
I recommend Wellgo MG1 QRD (Quick Release) Pedals, light and strong:
http://www.ebay.de/itm/Wellgo-QRD-MG...item2576d33186

Extensive list of Dahon parts and upgrade options with weights: http://handsonbike.blogspot.de/2012/...ht-weenie.html