Were do the pros put the lead tape (if they use lead tape) to mantain the balance of the racquet?(under the grip, above the handle,...?)
There is no one place they put it. Even the same pros may put it in different places on each frame, since all frames come off the line slightly differently. The idea is to make them MATCH, and that requires different things for each frame. They aren't maintaining the balance of a specific frame, they are making the balance of all their frames match each other. Generally speaking, if you're trying to add weight, but maintain the balance of your frame, you can do one of two things:
- Add weight exactly at the balance point of the racquet (NOTE: this does not mean 6 0'clock necessarily, as each racquet has a different balance point to start with).
- Add weight somewhere on the head, and then counterbalance it with weight in the handle.
How you choose to do this depends on what else you're trying to achieve. One of the most popular ways is to add weight at 3 and 9 o'clock on the head for stability and then counterbalance with the appropriate amount in the handle or under the grip.
Whichever method you use, it's a good idea to avoid guesswork, which means you need access to equipment that can measure the weight, balance point and swingweight of your racquets, at the very minimum. If you have this, you can also use the calculators on the USRSA website, which will give you many options for where to place weight (and how much) to achieve the desired effect.