A fat tyre bicycle is a type of bicycle that is designed with extra-wide tires that are typically between 3.8 and 5 inches in width. These wider tyres are designed to provide increased surface area and traction, which allows riders to ride on soft, unstable terrain such as sand, snow, mud, or gravel more easily.
Fat tyre bicycles typically have a wider frame and fork to accommodate the wider tyres, and the tires are run at lower pressures than regular bike tires, which allows them to conform to the terrain more easily. The wide tires also provide a cushioning effect, which makes for a more comfortable ride on rough terrain.
Fat tyre bicycles were originally designed for use in snowy conditions, such as winter cycling or snow biking. However, they have become popular for other types of terrain as well, such as sand, mud, and rocky terrain. They are also popular for bikepacking and touring, as the wider tires can carry heavier loads over rough terrain.
While fat tyre bicycles can be heavier and slower than traditional bicycles on paved or hard-packed surfaces, they are incredibly versatile and can be ridden on a wide range of terrain. They are an excellent choice for adventurous cyclists who want to explore off-road or unconventional routes, and who value comfort and stability over speed and efficiency.