$50! Ok, now I gotta ask.. Where are you?!?
Dealers are NOT known for having the best service prices around, nor do the best work.
For the $50 I strongly suspect they did not take the carbs off the bike. Sounds more like a spray clean, flush and sync. Syncing up the carbs will make a big difference. I could see that done for $50
Patriot Guard Rider
2000 VN750 Sere (Serendipity)
1990 GL1500 (Ole Blue)
1986 VN750 EVie (project bike, heavy custom)
VROC # 11628 / 25000-H
ARVROC # 12 Coordinator and Crowd Control
OKVROC # 18 (H)
TNVROC # 45 (H)