Polini 280cc Main jet

Hello,i need to know the Main jet for my px.  The cilinder is a polini 208cc iron, mazzuchelli racing crankshaft 57 stroke,jl rz righthand exhaust, phbh 30 carburetor direct manifold malossi and malossi air below,original ignition kit, ignition time 19°. I live in south Spain ,here is 40° degree in summer, it's so hot. I'm using 130 main jet but is not good yet, cylinder rings sound a little when rev are middle-up regimen and spark plug its a little dry. I've tried moving up the jet needle but isn't the solution, now is on the second place.

Please, anybody can help me?