Internal change: advantages and disadvantages

Bicicleta plegable City Red

You’ve heard or seen him on an urban bike before. But what are the advantages and disadvantages of internal change?

An internal gearbox is a system analogous to an external bicycle gearbox, but using gears such as a motorcycle or car gearbox. The inner shift is located inside the rear wheel hub. They are available with 2, 3, 5, 7, 8, 11, 12 or 14 speeds. They are often used on small wheeled bicycles such as folding bicycles or touring and/or electric bicycles. The first internal gearbox was patented by William Reilly of Salford, England 1896, it had two speeds.

Today the most popular internal gearboxes are Shimano Nexus (3, 5, 7 and 8-speed), Shimano Alfine (8 and 11-speed), Sturmey Archer (3 and 5-speed) and Sram (2 and 3-speed).

Video of how it works:

 

As for its advantages we have the following:

  • It allows you to change without pedalling, perfect for urban cycling, with multiple stops at traffic lights.
  • Less breakdowns and maintenance. The gearbox is enclosed in a closed box where mud, dust, sand or water cannot enter. This way the mechanism is sealed in the bushing and lubricated and is not exposed to dirt or weather.
  • Long life also to the chain, which always works online. This allows you to cover it with a chainguard or even have it fully covered, protecting the rider’s clothing from grease and damage. A protected chain will keep the lubrication clean and last much longer than if it were exposed to the pleasures of time.
  • The shifting is smoother than with rear derailleur gearboxes and is more effective and does not duplicate. They show a gradual and regular increase from one speed to the next.

 

Its disadvantages:

  • They tend to be more expensive because the mechanics are more complex and they tend to have fewer speeds, although they are better used.
  • Due to its more complex mechanics it is almost impossible for the average cyclist to repair.
  • It increases the weight of the bike by a few hundred grams and shifts the centre of gravity towards the rear wheel, which can be undesirable.

The best way to know all the advantages that we have indicated I recommend you to try a bike with this type of gear.