Can somebody please tell me how to tell if tires are imbalanced?

My tires already have balancing weights and the vehicle is relatively new. Some one told me that I need to balance my tires. I personally am not sure how to identify imbalanced tires. Your help is appreciated.

why were you told to balance your tires? If tires are out of balance you would feel a shimmy at some speed… the other way is to have them checked at a tire dealer.

By shimmy, do you mean shaking?

yes

As stated previously, tire imbalance is something you notice, usually as a vibration through the steering wheel, or by the seat of yor pants. If there is no vibration felt, even when you ride in the backseat, you probably do not need balancing. Next you should inspect all 4 tires, and see if there is uneven wear. If all looks normal, you don’t need balancing. Most tire dealers now offer free tire rotation and balancing if they believe it necessay to keep the warranty valid. I have my Michelin tires rotated regularly this way, and appreciate the free inspection; in the last 50,000 miles of rotation they have not mentioned balancing. Properly balanced tires stay that way for a long time, unless they are abused.

How about a definition of “relatively new” vehicle?