I have been working recently on a 71 cb 750 that I purchased,I could not get #2 to fire ,I checked compression,spark they both seemed ok ,I could not get #2 bowl to fill with fuel,I also checked the bowl vents on advice from the forum,finally I pulled the carbs and found that #2 slow jet was stripped out and seemed to be broken off inside carb ,I purchased a used set of carbs and was wondering if I should just change #2 carb to my set or use the entire used set that I bought thanks for the help