Bakväxelns

Bakväxelns is a Swedish term that translates to "rear derailleur" in English. It is a component of a bicycle's drivetrain that is responsible for shifting the chain between the different sprockets on the rear cassette. This allows the rider to change gears, making it easier to pedal uphill or to achieve higher speeds on flat terrain.

The rear derailleur works by using a spring-loaded parallelogram mechanism. When the rider operates the gear shifter on the handlebar, a cable pulls or releases tension on the derailleur. This action moves the derailleur's jockey wheels, guiding the chain to engage with a different sized sprocket on the rear wheel. The size difference between the sprockets determines the gear ratio, affecting how much effort is needed to pedal and how fast the bicycle moves.

Modern rear derailleurs are highly sophisticated, often featuring precise indexing systems to ensure smooth and accurate gear changes. They are designed to accommodate a range of cassette sizes and chain widths, making them a crucial part of a bicycle's performance and versatility. The maintenance of the rear derailleur, including cleaning and lubrication, is important for optimal shifting performance and longevity.