For a 1.6 my book gives the following for dellorto DHLA 40's: 34mm chokes, 45 idle jet, idle air bleed 7850.1 (starting point), main jet 140, emulsion tube 7772.7, air corrector 160 (starting point and go leaner (bigger)), aux venturi 7848.3, accel jet 35-40, needle valve 1.75.
Note these are all starting points but should get a 1.6 running to enable finetuning.
Make sure you are getting enough fuel (supply and needle valve) as the std supplied needle is often the smallest size and could run lean at the top end.