This kit includes all necessary parts to make your own 

D725 (https://www.ebay.com/itm/296257010125) or

D825 (https://www.ebay.com/itm/295543021346) or

TILT525 (https://www.ebay.com/itm/296209019228) or

FLEXI125 (https://www.ebay.com/itm/296468179837)

To complete the kit you need:

1 - One the following bikes: Dahon Vybe D7 / Dahon Qix D8 / Btwin Tilt 500 / Carraro Flexi 121

2 - HONDA GX25 Engine

3 - Schwalbe Kojak 20x1.35 tyre ( for D725, D825 and Tilt 525) or Panaracer Minits 20x1.25 tyre (for FLEXI 125) 

4-  U-brake caliper

All relevant videos are available at DR1L channel