I've never had a bike with air pressure on the steering head, Its on the belt guard.  I forgot there was one on the steering head I've always used the one on left side by the rear tire.

I have wondered the same.  and maybe all air was not out because when you felt the tire it still felt quite hard.  The ride was not mushy at all, it just jerked the bars back and forth.  my best guess is that a rather small oject may have punctured it but not stayed in the tire (fell back out).

Hey guys just joined the forum today and would like to throw my two cents in. I decided in the spring of this year that I could change my tires myself. I always drag my wife to swap meets with me so I went looking for some tire irons. I was told by everyone that I would hurt myself and my bike would shake because the tires would be out of balance. I found a tire that had never been mounted but it was really old and dusty for $10. I bought it then found one for the rear and got a pair of tire irons off ebay. Now I'm a lifelong gearhead so I have done many car tires with  not so good tire machines. Worked in auto salvage for years. I got the tires off and the new ones mounted in about an hour. My hands were a little sore from arthritis and exertion but I got it done. The results were back tire no problem front tire had a hump around the inner tube valve. I took it off again a figured out that you can't tighten the valve nut until you put some air into the tire. Got the tire back on the right way but it wobbled  because it was warped in the direction that it leaned up against the wall while sitting for years. I talked to a friend who does tires on heavy equipment he said overinflate the tire leave it alone for 2 days don't ride the bike then let the air out down to 35#. I did this and everythings fine and my bike doesn't shake at any speed. I guess I got lucky. But it was hopping like mad when I first put that tire on!

The tube and tire had been on the bike for around 6 months to the tune of around 8000 miles.  It ran smooth as glass up until the problem started and does now again.  It still has around half of the tread (over  where the wear indicators are) left.  The stealership put the tire on.   I live on my sail boat on the Tennesee river and my workshop is one end of my storage cube so I can handle minor jobs but i really don't have the room, the tools, or the room for the tools to do a tire change.  I do my own oil changes, brake jobs and such but for tire work hell ith my living quarters as they are I jsut dont have the room ( give me a year we are looking for a permanent place).