PK 50 Xl with Sito Plus exhaust

Hi!

After my original exhaust rusted to pieces i bought a brand new sito plus exhaust. After that my scooter has a bit more power on low revs, but less power on hig revs. To get the best performance of my scooter i've understood that I need to rejet my carb. What size should my main jet be?

Carb. SHB 16.15

Main jet 65

Idle Jet 42

Is there anything else I should do to make my scooter work properly?