On Wed, 09 Jul 2003 18:42:29 +0200, "jacques"
wrote:

Some tires become "dry" (can I say this of a piece of rubber ?) and
develop cracks much before the wear out.

If the tires are stored near ozone generating motors, like furnaces,
pumps, freezers, etc... or constantly exposed to UV radiation via
untinted, sunny windows, they can crack and crumble long before they
wear out.

Some rubber and plastic compounds seem to be more prone to this than
others.

Barry