Our Matt geeks out on the differences between 700c and 650B wheels. Which rolls better and which, importantly is faster? Amongst other things, we chat about wheel and tyre sizes and what might be better for different types of riding before Matt gets his tape measure out and rolls about on a Welsh hillside. WARNING - some brake discs were removed during this test.

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We investigate the differences between the 700c and 650B gravel wheel sizes and explain what all those numbers on the side of the tyre wall really mean. We have a think about what wheel and tyres might be best for certain situations and terrain and carry out a very scientific rolling test to see which wheel size rolls further with identical, tyres, pressure, rider and conditions. What are your preferences? Let us know in the comments below.

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