》1/16 in thread

來源: 2010-08-26 11:24:55 [舊帖] [給我悄悄話] 本文已被閱讀:

A common test in the United States to check for excessive tire wear is to insert a one-cent coin into the tread to see if it has been reduced to 1/16 or 2/32 of an inch. If part of Lincoln's head is covered by the tread, the tire has a legal amount of tread. If all of his head can be seen, however, it is time to replace the tire. It's important to note that a tire that just passes the "penny test" could be still be dangerous when driving in snow and could increase the risk of hydroplaning.