[njsteve]

If stored properly the tires can last quite a long time without dry rotting but I would not recommend driving on them at any high speed.

Storing them in a cool dry place is a good start but they can't be left near any electrical equipment as the ozone that these electro-mechanical devices emit destroys rubber products. That's the problem most people run into when they store them in their basements...right next to the ventilation fans and heater/AC equipment.