I have a 1998 zx6r with 15K miles on it. When I am riding about 50mph, and I let go of the handle bars, the handle bars wobble. I don't feel the wobble when I am riding holding on to the bars.
Is this ok? Or are the front wheel/tire out of balance? Front tire chopped?
This is a MOST common feeling & sign that the front tyre is showing signs of a lot of wear. Check over the tyre & you will find it is a bit lippy or scalloped. Not that you have done anything wrong, but in a sportbike 90% of our stopping power is the front brakes so the tyre shows it as I mentioned.
If both tyres were new on the bike, then next to start showing signs of wear will be the rear. Usually most of us go through a front first then a bit later on it will be the rear.
Average tire life should be three years or less, regardless of use. You will see great looking tread, but age is not a good thing when it comes to being well balanced and safe. If you can afford it, get a good set to replace what you have and look into the appropriate rating for your expected use of this bike.
If it's not in the budget, have a reputable shop take a look at it to verify it is safe for putting more mileage on it. This may cost nothing and can give you some peace of mind before you put on some new rubber.