A carb sync is easy you can buy the card stick for less than the shop labor coasts to do your first carb sync. For inline 4s remove tank add a extended fuel line with a hard piece of pipe to join the 2 lines together, clamp them together, put the tank on prime ( PRI ) set the tank slightly higher than the bike be careful not to let it fall. Next remove vacuum caps on each intake tube some models on carb. It is a good idea to get 4 extra caps from a auto parts store usually 5/32 in size they usually split coming off. Slip the hoses on each vacuum port 1 to1, 2 to2,and so on. Put a fan in front of the bike for cooling, start it and allow the bike to come to operating temp. there is three adjusting screws 1 center and one on each side between the carbs. Start by making the out side carbs the same on the mercury scale then the center carbs. DO NOT REV ENGINE WHEN YOU LET THE THROTLE GO, TO FAST A SUDDEN VACUM CAN PULL THE MERCURY INTO THE ENGINE. You want the 4 tubes of mercury to be the same as close as possible an 1/8 of a inch isn’t a problem but no more than a half inch 1/4 preferred as max. On a 2 cylinder the process is the same except only one adjusting screw between the carbs the extra 2 hoses on the stick are not used. This usually takes longer to remove the tank and prep for this than the actual adjustment. I can do my ZRX 1200 in 20 minutes. The stick coast me 45 dollars and shop would charge 65. It is recommended to sync anytime you remove the carbs for service, jetting, or overhaul. If anyone has a ? or more detailed info just reply here. This is also done on fuel injected models.