Many new mechanics have to clean a carb 3 times before they get it really clean! There is a Pine Sol soak method that is very popular.
Or try using a fule cleaner additive like Sea Foam.
Add it to the gas in the specified amount and ride 2 or 3
tanks full to get the most cleaning. Not as good as
a mechanical cleaning, but it does help. Over a period
of months, my DH has used Seafoam, Berryman's B12 and
Chevron Techron and has gotten his Nighthawk carbs to running well.
Now, you know to add gas stabilizer to your fuel for storage.
We use Sta-Bil but Startron is getting a lot of press.
Scoot Safely,