There's nothing tough about learning to jet a carb. Especially a slide valve carb like a PHBG. Get the bike to start, and run, then you set the main jet, then the needle, then the pilot jet. You're done..... :-)
The biggest problem I see with people are carbs on this forum are the tendancy to pick HUGE carbs. a 24mm carb will support FOURTY EIGHT horsepower. Think about that next time you want to get a 21mm carb. You can make 12hp on a 12mm carb.
Big carbs = crap jetting. Don't use big carbs.
Futz with the starter jet if the thing doesn't start easily.