So I just happened to look at my front tire the other day & realized how cracked it is.  Just for kicks I also checked the rear tire and it wasn’t quite as bad with cracks long ways but had a few deep ones the short way.  Checking on the age of the tires reveals them to have been manufactured in 2005 (back) and 2006 (front).  Pretty old for a set of tires.  The front one’s always had a slow leak so I’ve had to put air in it every week.  Picture is my method of jacking the bike up – put on center stand, put bricks under front of crankcase, tie handlebars back with bungee cords (and put sponge between brake lever & grip to keep brake pads from being pushed out).