A fatbike (also called fat bike or fat-tire bike) is an off-road bicycle with oversized tires, typically 97 mm or larger and rims 55 mm or wider, designed for low ground pressure to allow riding on soft, unstable terrain, such as snow, sand, bogs and mud. Fatbikes are built around frames with wide forks and stays to accommodate the wide rims required to fit these tires. The wide tires can be used with inflation pressures as low as 340 hPa to allow for a smooth ride over rough obstacles. A rating of 550–690 hPa is suitable for the majority of riders.

As the popularity of fatbikes has expanded, fatbike specific events (races, race series, tours, and festivals) have emerged. Examples include the Snow Bike Festival, the annual Global Fatbike Summit (since 2012), the Fatbike Birkie race which is part of the Great Lakes Fatbike Series (2014–2015 season: 8 races held across 3 states), the US Open Fatbike Beach Championships (inaugural, 2015), the USA Cycling Fat Bike National Championship (inaugural, 2015), the 45Nrth Fatbike Triple Crown race series and the UK Fatbike Championships (inaugural, 2013).

There are even now Iditarod races in Alaska to complete the same route normally only attempted with dog sleighs

In South Africa, fatbikes are used to ride on soft sand like beaches and sanddunes in desert areas, and this makes these areas much more accessible to tourism and sport

Coming soon – a directory of Fatbike resources in South Africa