I now
park my tires on plywood, on this concrete during the winter. It is a chemical
reaction between wet concrete and tires parked too long. Asphalt and gravel
do no harm.
Brian
Agree gravel won't hurt the tire when storing however tire makers tell us;
Goodyear;
Don't store tires in an area that is wet, oily or greasy
*Don't store tires where they are subjected to direct sunlight or
extreme temperatures
*Don't store tires near electric motors or other ozone-generating
sources
*Don't store tires on black asphalt or other heat-absorbent surfaces
*Don't store tires on or adjacent to highly reflective surfaces such
as sand or snow.