Rolling tire change.

Yesterday went out for a ride with my dad and my brother.  We averaged 11 mph, 10 mptc (miles per tire change) My dad got a couple of flats last week and about 7 miles into the ride he got another then 3 miles later another.  After 20 minutes of examining the tire I found the sliver of glass that punctured the tire (this glass was saved for centimental reasons)  After a short ride around clive and into downtown we stopped a java joes.  For some awesome sandwiches (they sure should be for 6.50!)  Then up neal-smith trail back to beaverdale so my brother could check out the new bike world store.  (Still need that new bike (ps if anyone is thinking I need to get Courtney that bike it's the Gary Fisher full suspention sram x-9 29")). When we were ready to leave the front tire was flat again.  I don't know how some people manage so many flats I've rode miles of gravel on a road bike and only get flats on bike trails.(Maybe it's because the bike trails are so crappy and no one ever cleans the glass off of them)