wide tyres. Why 4" wide tyres? The massive Fat Bike tyres allow the rider to get better traction because of the greater surface area on the tyre. This allows the rider to conquer a greater variety of terrain which would otherwise be incredibly difficult. Where do I ride a Fat bike? On a Fat Bike you can ride wherever you please: up mountains, down mountains, around mountains, over sand dunes, along the beach, through mud, over thick snow or through fresh powder. You can ride our Fat Bikes anywhere.