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7-Speed Bike vs. 21-Speed Bike

7-Speed Bike vs. 21-Speed Bike

7-Speed Bike vs. 21-Speed Bike- Introduction

New cyclists and bikers who have ridden for a long time often have doubts about the different speeds of their bikes. They often take time to search for the perfect bike for their riding conditions and goals. They’ve come to realize that having the right bike with the correct number of gears needed at each time is essential.

So let’s talk about gears and drive trains of 7-speed and 21-speed bikes, and examine the main differences between the two. 

What is a 7-speed bike?

A 7-speed bike has a single sprocket next to the pedals. Faster bikes can have up to three. A second gear lever on the handlebars is not necessary. Also, the shifting process is the same as for most bikes.

7-speed bikes are usually recommended for bikers progressing from lower speed bikes (such as 3-speed) and who wish to tackle harder terrain. 7-speed bikes provide sufficient gearing ratios for you to bike on bumpy or inclined terrain, while having a higher gear to build momentum on downhill segments. 

What is a 21-speed bike?

The number of gears on a bicycle is calculated by multiplying the number of front gears by the total number of gears in the rear. For instance, a 21-speed bike has triple chainrings in the front and seven cassettes gear in the rear. As its name suggests, this type of system provides you with 21 gearing ratios.

Once you have learned to master the skills of a 21-speed bike, you can enjoy longer rides, which will make you less tired. 

The difference between a 7-speed bike and a 21-speed bike

  • A 7-speed bike has seven different speed ratios for use in different conditions. A 21-speed bike has 21 different speed combinations.
  • The seven gears can be reached by the internal gears in the hub
    or by an external gearbox with a gear lever.
  • A 21-speed bike will have a 7-speed rear hub with three different chain links on the crank. Although it offers 21 different speed combinations, there will be overlaps in the various speed ratios available when switching to a different crown.
  • In a 7-speed configuration, it has a single front sprocket and 7 reverse with a single gear lever.
  • In a 21-speed configuration, it has 3 speeds with different speed ratios at the front and 7 at the rear wheel, making it 21-speed. 

7-Speed Bike vs. 21-Speed Bike

 Who needs a 7-speed bike?

The decision whether or not to jump on a seven-speed bike on a 21-speed bike depends on where you intend to go biking. 7-speed bikes may mean a bigger “jump” in effort required when changing from one ratio to another. This means when facing a steep incline, it is best to anticipate by changing gears early.

While a 7-speed bike requires a lot more effort to run, it does not take long to master if you are changing from a lower speed or fixed gear bike.

Who needs a 21-speed bike?

If you’re more interested in enjoying the view from the saddle, choose a 21-speed bike (triple front chainrings and seven rear cassette gears). It’s a more effortless ride as typically, there is some overlap between gear ratios available on each chainring.

However, be ready to spend more time covered in grease due to a more complex drive train. It may require more effort for you to clean the drive train thoroughly.  

How to use 21-speed on a bike

Most bikes are equipped with gears to help bikers tackle all kinds of terrain. Most bikes come marketed as 7-speed, 14-speed, 21-speed and so on. The number of gears on a bicycle is calculated by multiplying the number of forward gears by the total number of gears in the rear gearbox. For instance, a 21-speed bike has a triple link in the front and seven speeds in the rear. Once you have learned to master the skills of a 21-speed bike, you can enjoy longer rides, which will make you less tired.

  • Understand the Gear Setup: The front chainring on the bike has three rings and is controlled by the left handlebar shift lever. The chain should be in the largest “big ring” during flats and the descent, in the medium ring when riding on a moderate climb, headwinds, or during the steep hills.
  • How to shift: Always pedal when you want to shift; otherwise, the chain may fall off or jump gears. The front chainring must first be replaced for larger adjustments, and the rear wheel should be a minor modification to help adjust the resistance.
  • Think ahead: Trying to change gears in the middle of the climb is taxing on your energy level and can be challenging to do. Also, do not go at a slower speed when approaching a stop.
  • Make the gears work for you: The purpose of the different speeds is to help cyclists maintain a constant pace, whatever the terrain, wind, and fatigue of the feet. Maintaining a fast and continuous rate of 80 to 90 rpm can significantly increase endurance. To make the gears work for you, switch to a lighter gear when you approach a hill or start to tire. If your pace starts to slow down for any reason, take this signal to move at a slower speed. On the other hand, take advantage of flats, descents, and tailwinds, to run at higher gears. This will help you increase your speed, keeping the same cadence and the same level of effort.
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