A gear case, also known as a chain case or chainguard, is an enclosure for the
bicycle chain
A bicycle chain is a roller chain that transfers power from the pedals to the drive-wheel of a bicycle, thus propelling it. Most bicycle chains are made from plain carbon or alloy steel, but some are nickel-plated to prevent rust, or simpl ...
and
sprocket
A sprocket, sprocket-wheel or chainwheel is a profiled wheel with teeth that mesh with a chain, track or other perforated or indented material. The name 'sprocket' applies generally to any wheel upon which radial projections engage a chain pas ...
assemblages commonly employed by
utility bicycles
A utility bicycle, city bicycle, urban bicycle, European city bike (ECB), Dutch bike, classic bike or simply city-bike, is a bicycle designed for frequent very short, very slow rides through very flat urban areas. It is a form of utility bicycle ...
. It serves to protect the cyclist from being soiled or trapped in the
chain rings and tends to fully enclose the drive train. It may also contain an oil bath to keep the chain
lubricated. Modern examples are usually
moulded in
plastic
Plastics are a wide range of synthetic or semi-synthetic materials that use polymers as a main ingredient. Their plasticity makes it possible for plastics to be moulded, extruded or pressed into solid objects of various shapes. This adapta ...
. Similar devices may be found in connection with chains used on larger vehicles and machinery.
Gallery
See also
*
Luggage carrier
A luggage carrier, also commonly called a rack, is a device attached to a bicycle to which cargo or panniers can be attached. This is popular with utility bicycles and touring bicycles.
Bicycle luggage carriers may be mounted on the front or r ...
References
bicycle glossary entry for "Chain case"from
Sheldon Brown's website
Sheldon Brown's bicycle glossary entry for "Gear case"
Bicycle parts
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