Hello Vespa people...
I need some advice..
I have pk 50 xl 1989 that I would love to upgrade to Pollini 133
My plans are to have set up like this:

24 Dellorto carb
Pollini right hand exhaust
Pollini cylinder and piston
2,56 primary gear...
What else do I need to change or do??
Thank you

You have to change the crankshaft to a type with 51 mm stroke. For this you have to split the engine. As I see you want to install a 2,56 primary gear - for this you have to split the engine anyway.

Thanks