View source for Carrying wheel

{{ref improve|date=November 2014}}
A '''carrying wheel''' on a [[steam locomotive]] is a wheel that is not driven; i.e., it is uncoupled and can run freely, unlike a coupled or [[driving wheel]]. It is also described as a '''running wheel'''<ref>Wörterbuch der Industriellen Technik, Dr.-Ing. Richard Ernst, Oscar Brandstetter Verlag, Wiesbaden, 5. Auflage, 1989, {{ISBN|3-87097-145-2}}.</ref> and its axle may be called a '''carrying axle'''. A carrying wheel is referred to as [[leading wheel]] if it is at the front, or a [[trailing wheel]] if it is at the rear of the locomotive. 

==Weight distribution==
In particular reference to steam engines, the carrying wheels have a very important purpose of allowing the engine's [[weight distribution]] to be altered. For example in the use of leading wheels it would allow the boiler to be located further forward of the driving wheels, the weight of which counters the leverage imposed by the drawbar and the load of the pulled wagons/cars about the fulcrum of the rearmost driving wheel. Similarly the trailing wheels can move the fulcrum to the rearmost trailing wheel. Such change can dramatically improve the operating speeds of engines and their [[tractive effort]].

==References==
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{{Locomotive running gear}}

[[Category:Steam locomotive technologies]]

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