I had a strange thing happen today. I am currently using Continental Contact tires the side wall list the max pressure as 85 psi. I noticed that my rear tire was flat this morning. After removing the wheel and tire I ran the tube through a tub of water and quickly found a slow leak. I patched it but before remounting I checked the tire for cuts and anything embedded in it. It was perfectly fine. I remounted tube and tube (I normally run right at 80 psi) using my shop hand pump. Right as I was reaching 80 PSI the tube exploded with loud bang. After my heart beat got back to normal. I removed the tire and inspected the tub and it had a six inch split in it. Figuring I had missed something inside the tire I carefully reinspected it inside and out and could find nothing wrong with it. At this point I remember that I had a Panaracer Flat-Away Tire Liner sitting on my shop shelf. I decided now was good time to install it which I did. With tire and new tube remount I started to inflate with the floor pump. Once again as I was nearing 80 psi the tube force ably blew out. To say I was a bit upset is an understatement. My floor pump is Zefal HP Husky and it has a built in pressure gage. I have been using this pump for over two years with no problems what so ever. My first thought was that the pressure gage must be really off. So again I dismount tire and tube. Just to be sure I now carefully go over the tire with a fine tooth comb for the third time. Nada! I check the wheel, spokes and the rim edges for burrs. Nothing! So I once again remount tire with yet another new tube. Suspecting that the pressure gage on my shop pump is seriously out of calibration. I decide to use my Topeak Road Morph pump (it has an in-line gage) that I carry on the bike. Heck it will be good practice I think. I pump it up to 80 psi and set the tire against wall. while I replace my pump onto the bike. All of sudden the third tube blows. All three tubes have split open. All three are the proper size and from 2 different manufactures. I dismounted the tire and tube and inspected everything yet again. Nothing was found out of the ordinary. Grasping for straws I figured that perhaps the first blow was just a weak tube. For the second two I decided that perhaps the Panaracer Flat-Away Tire Liner took up to much space in the tire and caused the tires to split. I removed it and installed my last tube. I decided it would be a good idea to use a tire pressure gage. I found that the three gages that I have do not work with a darn on presta valves. So much for that idea. I used my floor pump to slowly inflate the tire and stopped at 60 psi. All is holding well and the tire is firm to the touch.
Thinking about this I find it hard to believe that three tubes could have been weak and bad. I find it hard to believe that two different tire pumps with built in gages both have bad gage readings. I have been using 80 psi on these tire and a tube combos for the past two years.
Am I over inflating my tire when I take them to 80 psi? Have I just been lucky up to this point? What am I doing wrong? What kind op tire pressures do you all run on 700c x35 tires. The Continental Contact tires came stock on my LHT and I have had no problems till now. I am scratching my head help!!