Since bicycle and wheelchair wheel spokes are only in tension, flexible and strong materials such as synthetic fibers, are also occasionally used. 500 pounds-force or 2,200 newtons) of tension, they are used at a fraction of this load to avoid suffering fatigue failures. While a good quality spoke is capable of supporting about 225 kgf (c. High quality bicycles with conventional wheels use spokes of stainless steel, while cheaper bicycles may use galvanized (also called 'rustless') or chrome plated spokes. These include bicycle and wheelchair wheels. Some types of wheels have removable spokes that can be replaced individually if they break or bend. These are also used in wheelchairs, motorcycles, automobiles, and early aircraft. Tension spokes įor use in bicycles, heavy wooden-spoked wheels were replaced by lighter wheels with spokes made of tensioned, adjustable metal wires, called wire wheels. Also, the dishing allows the wheel to compensate for expansion of the spokes due to absorbed moisture by dishing more. They are also dished, usually to the outside of the vehicle, to prevent wobbling. The other wooden spokes show no significant change. In a simple wooden wheel, a load on the hub causes the wheel rim to flatten slightly against the ground as the lowermost wooden spoke shortens and compresses. In early motor cars, wooden spoked wheels of the artillery type were normally used. The original type of spoked wheel with wooden spokes was used for horse-drawn carriages and wagons. Spokes can be made of wood, metal, or synthetic fiber depending on whether they will be in tension or compression. The spoked wheel was in continued use without major modification until the 1870s, when wire wheels and rubber tires were invented. Ĭeltic chariots introduced an iron rim around the wheel in the 1st millennium BC. depict the usage of chariots with spoked wheels. Neo- Chalcolithic/proto-historic period (1800-1200 BCE) paintings in various regions of India such as Chibbar Nulla, Chhatur Bhoj Nath Nulla, Kathotia, etc. They moved deep into the Greek peninsula where they joined with the existing Mediterranean peoples to give rise, eventually, to classical Greece after the breaking of Minoan dominance and consolidations led by pre-classical Sparta and Athens. Soon after this, horse cultures of the Caucasus region used horse-drawn spoked-wheel war chariots for the greater part of three centuries. Earliest physical evidence for spoked wheels were found in Sintashta culture, dating to c. The spoked wheel was invented to allow the construction of lighter and swifter vehicles.

Galvanized vs stainless steel spokes