I’m looking to buy a new mountain bike (£3k budget). The one I’m riding is so old it has 26-inch wheels. Now I’ve got to decide between 27.5 and 29 inch wheels. I’m 5ft 8 and ride trails rather than ...

What is the 650b or 27.5in wheel standard? If you ride a mountain bike or gravel bike, you may have seen or heard of 650b/27.5in wheels – or your bike might be fitted with them – but what are the ...