Pick the jet you need for your Dellorto SHA or PHBG carburetor.
For tuning tips, check out Garage. The worlds largest moped build database. Here are the list of the top builds in garage using this jet. Use Garage as a guide to what jet you need.
Some Dellorto SHA Builds and the Jets they are using. SHA Builds
Some Dellorto PHBG Builds and the Jets they are using. PHBG Builds