The best wheel size for bicycle touring can be the subject of much debate amongst cyclists, and heated discussions often ramble on for several days in various forums and Facebook groups. Over the course of several long distance cycling trips around the world, I have come to my own conclusions which is the best size, and to cut to the chase, it's 26 inchers. Here's why…
Firstly, touring bicycles carry quite a bit of weight in terms of luggage and the weight of the cyclists themselves. This can put considerable strain on the wheels, especially when cycling over rough roads, and every now and again, a spoke will get broken. 26 inch wheels have shorter spokes than their 700c counterparts, and therefore they are by definition stronger.
Another reason that the best wheel size for bicycle touring is 26 inch, is that they are the most popular wheel size found throughout the world. This means that buying tyres, inner tubes and even new rims should they be needed is much easier in less developed countries. I learned the hard way when I cycled to Africa on 700c wheels, that I would have been far better off on 26 inch wheels, and ended up getting new tyres and inner tubes flown out to me at a great expense.
Being able to fit fatter tyres on 26 inchers is also a trait that makes them the best wheel size for bicycle touring. Whilst skinny tyres are required for high speed road racing, they are less than desirable for bicycle touring, especially on rough roads. Fatter tyres will give better grip, and this is most noticeable on sandy sections. Again, when I cycled through the deserts of Sudan, although I managed it on 700c wheels, life would have been a lot easier with 26'ers.
Of course, if a tree falls on your bike like one did with mine in the USA, even the strongest wheel in the world will buckle. Still, there were no broken spokes though!
So, short, sweet, and to the point. In my opinion, the best wheel size for bicycle touring is 26 inch, and indeed this is the wheel size I have chosen for my current expedition bicycle. I'm certainly not saying that I will never throw a spoke again, or will be able to find spare tyres in every country I cycle through, but overall, having 26 inch wheels for bicycle touring makes far more sense than having 700c wheels.