The more speeds you have on your bicycle, the smoother it is to shift and tackle varied terrain with slopes. However, gears can also help you maximize your energy output to reach higher speeds on flat terrain, so it’s all in how you use your gears. What is the main difference between a 21-speed and a 24-speed bike?
The main difference between a 21-speed and 24-speed bike is how many sprockets they have in the rear cassette. On a 21-speed bicycle, you typically find 3 front chainrings and 7 rear sprockets, which add up to 21 possible gear combinations. By adding a single additional sprocket, you add 3 more possible gears to the bike, making the total 24.
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What Is The Difference Between An 21-Speed And A 24-Speed Bike
Many people mistakenly believe that a larger number of gears on a bike equals more speed, but ‘speeds’ is a misnomer.
The difference between a 21-speed and a 24-speed bike is an additional rear sprocket.
The 21-speed is a 3*7, meaning it has three chainrings up front and a seven-sprocket cassette.
Meanwhile, the 24-speed is a 3*8 with one more sprocket.
Is It Better To Have More Gears On A Bike
Asking ‘is it better to have more gears on a bike’ is the wrong question. Instead, you should ask, ‘when is it better to have more gears on a bike, and what size gears do I need?’
It is better to have more gears on a bike when you deal with extremely varied terrain, ascending and descending varying slopes as a part of your regular ride.
For example, commuters in flat areas and people who prefer mostly level leisure paths for beach cruising won’t need a ton of gears, but they are a must-have for most MTB riders.
As for the second part of the question, the sprocket sizes usually depend on what kind of ride and which bicycle you use.
Most road bikes have additional high gears because it helps them move faster with ease. Alternately, mountain bikes tend to have more low gears to climb hills.
21 Speed vs 24 Speed Mountain Bike: Which Is Better
When comparing a 21-speed versus a 24-speed mountain bike, it’s essential to look at the terrain.
If you plan to cover moderate inclines, especially if they aren’t overly steep, stick with the 21-speed bike. This is a case of less-is-more.
On the other hand, when you are dealing with incredibly steep terrain, the 24-speed mountain bike is better.
The more drops, jumps, sharp hills, and downhill slopes you plan to ride over, the higher the chance of needing those extra three speeds.
More importantly, you’ll have smoother gear shifts, which is vital at higher speeds or greater difficulty levels.
If you’d like a visual demonstration of the differences between a 21-speed and a 24-speed bike, check out this video from Fat Biker Vaibhav. They give a quick and straightforward, easy-to-understand explanation.
21 Speed vs 24 Speed: Which Is Cheaper
You can find great, reasonably priced bikes in both 21-speed and 24-speed.
However, the 21-speed bicycles have become so common that they are often the cheaper option.
A 24-speed bike will be at the top end of high-performance bicycles, while the 21-speed occupies a niche somewhere in the mid to high end, covering both.
The 21-speed bike has become a staple for mountain bike riders and road bike enthusiasts alike.
However, you will also find 21-speed hybrids, commuter bikes, touring bikes, and even cruisers. This particular gear setup is by far the most sought-after of all the options.
What Is A 21 Speed Bike Good For
A good 21-speed bike is ideal for two types of riders. First, the road bike enthusiasts who enjoy endurance rides, challenging themselves, and going fast are well-suited to ride with more gears.
Most long roads have some variation, and hills are inevitable.
Secondly, mountain bike riders often have 21-speed bikes for smooth rides over rugged terrain.
MTB riders either have a challenging climb going uphill or a swift, bumpy ride when heading back down.
How Fast Can A 21 Speed Bike Go
A 21-speed bike can only go as fast as the rider and conditions push it. The term ‘speeds’ has nothing to do with how much power you put into a bike.
If you want to go faster, it would be best to work on your physical fitness.
Most riders only average 10-15 miles per hour. However, professionals and experienced amateurs can double that, easily reaching speeds up to or exceeding 25 mph.
A fast rider might double that speed again on downhill slopes, going 40-65 mph, though typically this is over a much shorter distance, and gravity helps.
Best 21 Speed Bike
- Enhance comfort and performance with the 18-inch aluminum suspension frame, while the 29-inch wheels fit riders 5'4" to 6'2" tall
- Element suspension fork smooths the bumps and increases control
- Effortlessly switch gears with the 21-speed rear derailleur equipped with SRAM twist shifters
- Alloy wheels with quick-release front, Superior braking performance of the alloy front and rear disc brakes, reliable stopping power for enhanced safety and control
- Assembly Tip: Ensure wheel is as centered between the fork legs, if quick-release lever closes easily, open and tighten the adjustment nut further, if difficult to close, open the quick-release lever, loosen the adjustment nut a little, and try again
If you’re looking for the best 21-speed bike, I recommend the Mongoose Impasse Men’s Mountain Bike from Amazon.
These incredible bikes have a 21-speed rear derailleur with SRAM twist shifters so that you can change gears quickly and smoothly.
Plus, the Element suspension fork offers excellent control and helps absorb shocks.
The lightweight yet surprisingly durable aluminum frame won’t weigh you down. Moreover, the alloy wheels and dual disc brakes are reliable and rugged.
Learn more about this outstanding Mongoose bicycle by clicking right here.
A good 24-speed bike is indispensable if you plan to handle steep slopes.
While the 21-speeds are more common, pros and those who have been riding for a long time understand that adding more gears means keeping your cadence with ease.
Maintaining a steady rpm rate helps prevent unnecessary muscle fatigue. You will be able to ride further with less effort.
What Does 24 Speed Mean On A Bike
24-speed typically means you have 3 front chainrings and 8 rear sprockets or a 3*8 gearing setup.
However, it also means you have plenty of high and low gears to help you pick up speed on flat areas and handle the highs and lows of varying slopes with ease.
Additionally, the extra three gears should help you shift more smoothly from one size sprocket to the next because having more gears means a more negligible size difference between them.
How Fast Can A 24 Speed Bike Go
A 24-speed bike will go as fast as you pedal it, plus a little more if you have a good wind behind you or heading downhill. It is the rider, not the bike, that determines the bike’s speed.
However, to put it in perspective, the stats below are mountain bike averages courtesy of Pedal Chile.
- The average speed for a mountain biker is 10 mph (16 kph) on singletrack.
- Downhill 12 mph (19 kph)
- Uphill average 8 mph (13 kph)
- The average speed for pro/semi-pro cross-country MTB is 9 mph (14.5 kph)
- Finally, the average downhill pro speed is 17 mph (27 kph), with peak speeds upwards of 30 mph (48 kph)
Road bikes are more aerodynamic and tend to move faster. Of course, the paved road also helps make it easier to reach high speeds.
According to Roadbikebasics, “The majority of riders can average a speed of about 15 mph on a one hour ride. A good speed for a beginner is 10 mph, but you should be able to get to 15 mph pretty quickly. If you start training every once in a while, you could get your average up to 18 mph, but training on a regular basis could get you to 22 mph.”
Best 24 Speed Bike
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The Tommaso Imola Endurance Aluminum Road Bike from Amazon is the best 24-speed bike.
This high-performance road bike can handle changes in terrain like a pro. Moreover, it has compact geometry for a comfortable ride.
Imola’s Shimano Claris R2000 gears are smooth and versatile, and its 700c tires help you cover long distances more efficiently.
Best of all, Tommaso has an industry-leading lifetime warranty.
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Helpful Tips To Know About 21 Speed vs 24 Speed Bikes
Getting the speeds you need is mostly about how and where you ride.
That said, both road bike enthusiasts who need to reach peak speeds and mountain bike riders who want to climb the highest mountains and then descend again in style need more gears than the average commuter or leisure rider.
Here are more helpful tips to know about 21-speed versus 24-speed bikes.
- More gears mean more complexity, leading to an increased chance of mechanical failure. The more parts you have, the greater chance of something breaking and the more things you need to replace. Resultantly, the best bike for you may be the one with the fewest gears to accomplish your goals. For some riders, you need all those gears. If you don’t, opt for fewer gears because it can save you time and money.
- Most bicycles have speeds 1, 3, 7, 18, 21, 24, or 27. The more speeds or gears on your bike, the easier it is to maintain your cadence when going up and down hills. Cadence is how many revolutions per minute you move your crank, and keeping a steady pace is better for you and your bicycle.
- The sprockets on your bike are also called cogs or gears on the back tire, typically as part of a cassette. However, the sprockets in front are often called chainrings. The difference is position. All sprockets are flat, circular pieces of metal with teeth around the edges that slip into the spaces inside your bike chain. The crank moves the sprockets, and the sprockets drive the bike no matter what you call them.
Choosing the right bike often means comparing a 21-speed versus a 24-speed and deciding which is better. It can be very frustrating, especially if you are a newer rider.
If your goals are moderate and your terrain is not too steep, stick to a 21-speed. This style is more common, cost-effective, and definitely sufficient for an average rider.
However, if you want to push the limits and go for the big hills, or there are numerous steeper, smaller hills in your path, a 24-speed is worth the investment because it will help avoid unnecessary fatigue.
Either way, you’ll enjoy the ride more with a bike that fits your needs.