A mountain bike or mountain bicycle abbreviated MTB or ATB all terrain bicycle is a bicycle created for off-road cycling. This activity includes traversing of rocks and washouts and steep declines on dirt trails logging roads and other unpaved environments activities usually called mountain biking. These bicycles need to be able to withstand the stresses of off-road use with obstacles such as logs and rocks. Most mountain bikes use wheels with rims which are 559mm in ISO sizing colloquially referred to as 26-inch although the term is inaccurate as it covers too many rim and tire sizes to be meaningful. Wheels used on mountain bikes usually use wide knobby tires for good traction on uneven terrain and shock absorption. |