My wheels are 700s and my Marathons have 38C (and ’38mm wide’) stamped on them and recommend a pressure of 60-85 PSI. So, I bought Specialized 700 x 28/38 inner tubes and pumped them up to 75 PSI. I like my tyres to be rock hard, but I found 75 PSI to be adequate. Yesterday, I decided to use the automatic pump at a Somerfield petrol station in Shoreditch, and as normal, I pumped up to 75 PSI. About 20 seconds later as we were waiting at a set of traffic lights my front inner tube exploded. Luckily I wasn’t actually sitting on my bike at the time, or worse still on the move. I can only think that either I’m using the wrong inner tubes, or the speed at which the tyre was pumped up had weakened the inner tube or its seam. It was quite an impressive blow out, if not a little inconvenient.
Upon hearing my inner tube explode, a guy behind me shouts from his white van “We’re going South of the river if you want a lift?”. I declined, explaining that I would change it for a spare, but thanked him for the offer. It wasn’t a transit van, and neither he nor his female passenger looked like your typical white van drivers, but still; a white van man offered help to a cyclist in need, and that counts for something in rush hour London.
A very long vehicle appeared to have dropped its very long and very heavy cargo underneath the disused (being revamped) railway bridge by Shoreditch town hall this evening. Fortunately, it looked like no-one had collided with either the lorry or its load.