Puncture

Much of yesterday's ride was on canal towpaths. Not quite as much as I had planned, because part of the towpath near Denham was closed for repair work, and I had to make a diversion through Ickenham.

But the main point is that yesterday was the first time this bike has handled a fair distance off paved roads. It was OK, but it wasn't really in its element on the rougher surfaces.

To begin with I was taking things pretty carefully, but once I got used to it, I relaxed and just bashed on as normal. So it wasn't a great surprise to get a puncture.

In truth, the soft tyre only became apparent when I was almost home, so I guess it probably wasn't caused by something on the towpath. Rather than fix it there and then, I ended up pushing the bike the last couple of miles, and fixing it this afternoon. A tiny tack had gone straight through the tyre into the inner tube. Hardly the end of the world, and it would have been easily fixed earlier in the day, as I had remembered to take the repair kit with me.

After putting everything back together again, and pumping the tyre up to full pressure, I did my usual spin round the suburbs to try it out. On getting home, I discovered that the recorded mileage was down from 5.39 miles (on the immediately preceding trips) to 5.35 on this one. So I checked back to to the distances I have logged for the same route over the last few weeks, and they vary by about 1%. No doubt some of this is due to taking a slightly different line on the same roads, but I wonder how much is down to different tyre pressures. The front tyre has never been soft, so it's only the difference between a fully inflated tyre, and one that is ready to be topped up. Surely that couldn't make a significant difference to the diameter on the road - or could it?