Last Sunday was my birthday, so on Saturday I went to the cycle shop and bought a track pump with a gage, as my bike tyres seemed to be very low. When I bought the pump I asked the guy that sold me the bike what my bike tyres should be pumped up to. He said that he thinks it is 85psi but it says on the side of the tyre.
I have been told the the more you pump up your tyres the easier it is to ride, and the less effort it takes, so I planned to inflate them as high as possible.
On Sunday I was doing some bike maintenance, I got my bike out of the garage and realised that I had a puncture in the front tyre. Perfect time to try my new pump. Swapped the inner tube with my spare one and I checked the tyre and it said max 85psi, so I thought the guy was right, I pumped it up to just over 80 psi then started to fix the puncture in the other tyre.
I then heard what sounded like a sonic boom, and the front inner tube had exploded with such force that it blew the tyre off the wheel. I wondered if I had inflated the tyre too much. When I removed the inner tube it had a split right down it.
The first puncture was called a snakebite puncture and it is when you get two holes about equal distance apart on your inner tube, this is due to your inner tube hitting your wheel whilst you are riding. the inner tube gets trapped between the wheel rim and a curb or something. I repaired this then but it back on the bike and pumped it up, I learned from the last time and pumped it up to 70psi, this is 15psi off the maximum.
As I was putting away my tools and I heard another sonic boom sound, the other inner tube had exploded. I didn't want to keep going through inner tubes without a reason, so I drove to work on Monday and took my wheel, two burst inner tubes and the pump with me. I took them back to the shop for an explanation, they tested the pump and said that the gage was 20psi out. So when I thought I was pumping up my tyre to 80psi I was actually pumping it up to 100psi. No wonder it exploded. The said unless you spend a lot on a pump the gage is usually inaccurate and used for a guide. He gave me another pump that he said was about 7 psi out and told me to inflate my tyres to 60psi, which should be enough.
I felt quite nervous pumping up the new tyres and ended up pumping them up to 50psi, on the ride to work this week they seemed slightly lower than I would like them, so I think I will take it up to 60psi.
Subscribe to:
Post Comments (Atom)
1 comment:
I'm gutted. I'm currently on the see-food diet and carry a heavy bag into work each day, which with all the weight, causes my bike tyes to ride like they're flat. It's hard work to cycle just the 15 mins to the train station.
I've always wondered if pumping them up with a heavy duty pump would work - but it sounds like they'd probably just end up exploding.
Curses! Guess I better just lose some weight.
Post a Comment