To help you fix your carburation problem you need to identify what throttle position is giving a problem.
For example; if you're holding the throttle wide open and it won't rev cleanly then change the Main jet.
This chart helped me understand which jets affect which throttle position...
PWK Carb.jpg
I also found it very important to only make one change at a time, then test the result.
When I bought my bike it was fitted with a 175 main jet, it wouldn't rev cleanly at WOT (wide open throttle). I fitted a 172 then a 170 and I'm very happy with it now.
I'm the same as F5, I think it would probably run even better with a 168, but I'm happy with the performance, it's fast enough
and I prefer to stay on the 'richer' side.
Good luck, Dave.
P.S. Don't forget to update us and tell us how you get on.