Derailleurs are one of the most important bicycle components, as they are what allow us to change gears and improve the performance of the bicycle. The rear derailleur moves the chain from sprocket to sprocket on the rear wheel, while the front derailleur changes the position of the chain on the chainrings. This allows you to have a variety of gears to face the different ups and downs of the route.
It is common to have to adjust the front derailleur, since it can often become unadjusted due to bumps, wear or simply because it has been replaced with a new one and this has to be adjusted with tools, because if it is not adjusted properly the gears cannot be changed properly. Badly adjusted derailleurs can be caused by issues such as a faulty chain, an excess of oxide or simply dirt in some part of the cable housing.
The rear derailleur is located in the rear wheel and is somewhat more complicated to adjust than the front derailleur. This system is what moves the chain’s position on the cassette allowing the driving force to be increased or decreased.
In cycling in order for the gears to be changed correctly, as well as adjusting the derailleurs, the gear cable also has to be properly adjusted, since it can become loosened and needs tightened.
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