Carburettor Securing Bolt Torque : 16-20Nm (12-15 lb ft)
Not available as a genuine Dellorto part. Made by Spaco Carburettors India.
Dellorto SI 26/26 carburettors have a venturi size of 24.95mm not 26mm.
When upgrading SI carburettors to a larger size, especially from 20/20D, the autolube system alone will not supply the required amount of 2 stroke oil and additional oil should be added to the fuel tank. I would recommend setting this carburettor for premix.
All Spaco SI carburettors come with the longer slow running fuel mixture adjuster screw used for electric start Vespa PX models. This cannot be swapped for the Dellorto slow running fuel mixture adjuster screw as it has a M5 x 0.5mm thread and the Dellorto is M5 x 0.75mm. Due to the longer fuel mixture screw the later type carburettor securing bolts and air box fuel mixture screw grommet should be used.