900 SS 40MM main jet size

[jsey]

What should be the pilot and main jet size for a 1981 900 SS that is stock and has 40 MM carbs with choke circuit

[Craig in France]

These are the PHM40 B carbs, yes?

In which case, your best reference is going to be the 1981 version of the owner's handbook. Because, unless I am mistaken, there wasn't a parts book issued for the 1981 SS, only for the earlier 1979-80 model which was fitted with PHM40 A carbs.

Unfortunately, I don't have a copy of that handbook ...

So all I can offer is the following 1982 MHR specification for PHM B carbs, velocity stacks and Contis:
Main: 135 max for the front, 140 for the rear.
Idle: 65 min
(Needle K5, slide 60/1, atomiser 265AB, choke jet 60, pump jet 45, needle jet 300).

HTH - a bit ...

[Craig in France]

A supplement to my previous message ...

Just found this in Ian Falloon's "Original Ducati Sport and Super Sport".

So pretty much the same, just a smaller idle.