USAF1blahblah, the basic point others are making is that a machine-built wheel needs to be re-tensioned after you've ridden on it a bit. That is, you need to have a mechanic (or yourself), go back to the wheel, true/align it, and then re-tension the spokes, i.e. tighten them back to high tension. After the mechanic/you do this, you can actually de-stress the spokes on your own by going around the wheel and squeezing very hard on adjacent pairs of spokes and/or, removing the wheel from the bike and applying pressure onto the spokes while the wheel is flat. If you get the wheels re-tensioned and then go back and de-stress the spokes a few times after each ride, this will help equalize all the tension on the spokes. Finally, for those first several weeks after this truing-re-tensioning, watch the true-ness of the wheel, and when it starts to go even just a little bit, either get it trued or re-true it again yourself. After going through this process once, twice, a few times, as long as you keep your tires well-inflated, your wheels should remain true and at high tension for a long time. As others above have pointed out, once the spokes are well-seated into the flange of the hub and their tension is high but stress is gone, the wheel will stay true for a long time. Remember to keep your tires well-inflated to protect your rims and spokes from those bad roads.