I have an 83 Venture Royale.I am having trouble with a lack of power once I reach 60 miles per hour.I took the carbs off and went through them.I have used sea foam to clean them.My question is how do you bench sync the carbs?I want to do that before I put them back on and sync the carbs.The bike sat for the winter and I am having problems for the first time.They have been acting up since I had to pull them to change the valve cover gaskets.Any advice would be great.Thanks.