For someone who’s just starting out with cycling, one of the first things that comes to mind is the kind of bike they should get. While choosing a bike, the FOREMOST question usually is- how many gears should a road bike have? Well, here’s the definitive answer:
For short rides (less than 30 mins at a time), a single-speed/3-speed bike will suit most people. For those that are slightly unfit, or plan to ride longer durations (2-3 hrs), a 7-speed bike is suited. For long rides multiple times a week, or rides on undulating terrain, a 21 gear bike is required.
This is just the broad answer though, and you do need to understand a bit more about how gears work, different types of geared bikes and gear ratios before you make a final decision.
Which is why I recommend you continue reading on:
Single Speed Vs 3 Speed Vs 7 Speed Vs 21 Speed Bike
First, let’s take a quick overview of the kind of bike that would be suited to you.
| Type of Bike | Single Speed | 3 Speed | 7 Speed | 21 Speed |
| Typical commuter profile | City Rider, new cyclist | City Rider, new cyclist | City Rider, new cyclist | City Rider, experienced cyclist |
| Terrain | Flat terrain | Mostly flat terrain | Flat + Undulating terrain | Flat + Undulating terrain |
| Max Ride Duration | 20-30 mins | 30-60 mins | 3-4 hrs | 4 hrs+ |
| Bike Cost | $300-400 (222-296 GBP) | $600-800 (444-592 GBP) | $600-1200 (450-900 GBP) | $600-5000 (450-3700 GBP) |
| Maintenance Cost | Negligible | $10-15/yr (7-11 GBP/yr) | $10-15/yr (7-11 GBP/yr) | $50-60/yr (37-45 GBP/yr) |
Lesser the number of gears on your road bike, the more effort you require to shift the gears. It won’t be a very smooth transition and hence you’ll need to anticipate the requirement of shifting to an easier gear, say before you start ascending a hill or descending.
Higher the number of gears, the easier the ride is. You’ll be smoother, faster and more comfortable on ascents and descents along with cycling on flat terrain. However, since there are more parts involved, it’s a bit more of maintenance.
You also will need a bit more skill to ride higher geared bikes like the 21 gear bike. You’ll need to understand the combination of chainrings and gears, will need to avoid cross chaining and get used to gear shifting using the front and rear derailleurs in tandem.
Sounds a bit complicated? Don’t worry, I’ll explain everything step by step.
What Are The Gear Parts of A Bike Called?
Now, you’ll find a lot of jargon laced advice on the internet on the kind of bikes to buy. Words like derailleur, gear sprockets, chainrings, etc are thrown around and can be a bit overwhelming for a complete newbie.
So, before we go ahead, let me quickly explain what all of these terms mean.
Gear Sprocket. In geared bikes, the rear hub (see photo below) is called the ‘gear sprocket’ or ‘gear hub’. It basically is a set of metallic disks that are combined into a single unit. Each disk has different number of teeth on it, which is what helps get varying amount of traction while cycling, i.e: what makes a gear ‘easy’ or ‘hard’.
Don’t worry if you didn’t get that last part, I’ll explain that in detail soon.
Chainring. The chainring refers to the metallic strip near the pedals of your bike. It also contains teeth on which your bicycle chain can fit on to. Your bike’s chain will go in a loop from the chain ring to the derailleur (I’ll explain that one next) to the gear sprocket. Single speed, 3-speed and 7-speed bikes have just a single chainring, however, 21-speed bikes have 3 chainrings with varying number of teeth.
Derailleur. The derailleur is a mechanical part that physically shifts your bike chain from a particular gear sprocket to another.
Now that you understand the basic mechanics, let me explain the last bit of technical detail before giving you the ACTIONABLE information that will help you decide the number of gears your road bike should have.
Gear Ratios- How They Help Understand Bike ‘Speeds’
Now that you have a fair idea on the different types of road bikes and the varying speeds in which they are available-let me further change the notion of ‘speeds’ that you might have.
A 21-Speed bike isn’t 21 different gears, rather 3 different ranges of 7 gears, which, when combined, become 21 combinations.
Sounds a bit weird? Stay with me. Let’s first understand gear ratios
Gear Ratio basically means how far your cycle travels for every rotation of your pedals. That ratio depends on two things:
- The number of teeth in your chainring
- The number of teeth in your chosen gear
Let’s say your chainring has 36 teeth and your gear has 12 teeth. Here, the chainring is 3 times bigger than the gear and the gear ratio will be 3:1. That is, for every complete revolution of your pedals, your rear wheel will revolve three times. This will be a ‘hard’ gear, requiring high effort, more muscle power from you.
Now, let’s assume you choose a different gear having 36 teeth. This means the gear is as big as the chainring, and the gear ratio is 1:1. For every complete revolution of your pedals, the rear wheel will revolve just once. However, this will be an ‘easier’ gear requiring less effort from you, and will be more cardio intensive as you will be pedalling at a higher cadence than in the first case.
Now, you’ll understand that gear ratios change to give you varying ‘speeds’ on a bike.
A single speed bike has a single chainring with no gears at the back.
A 3-speed bike has a single chainring with 3 gear sprockets at the back.
A 7-speed bike has a single chainring with 7 gear sprockets at the back.
A 7-speed bike has 3 chainrings up front and 7 gear sprockets at the back, which when combined, give 21 different speeds.
How To Choose The Right Gear Ratio For You
You just need to find the cadence (in technical terms rpm or revolutions per minute) at which you are most comfortable cycling for long distances (more than 30 minutes).
This basically requires a bit of trial and error on your next few rides, trying out all the various gear combinations, and figuring out the right tempo for you.
Say you are someone with lean legs. You are likely to feel comfortable pedalling fast, i.e: having a low gear ratio, as each pedal requires less force.
The more your increase the gear ratio, i.e: go into harder gears, the more force you need to apply for each pedal.
The trade-off is that the faster you pedal, the better cardiovascular workout you get, because the heart starts pumping more. The slower you pedal, on one of the harder gears, the more your leg muscles get recruited.
For the beginner, your goal should be to maintain your cadence throughout your ride. This means changing gears if you’re going through undulating terrain to maintain nearly the same cadence. Go into easier gears (low gear ratio) when you’re climbing and harder gears (high gear ratios) when descending.
Once you understand gear ratios and your optimal cadence well enough- you can start playing around with these.
That’s where the fun starts really.
You can design a Zone based cardio workout for yourself. The faster your cadence, the higher your Zone is likely to be.
For the un-initiated, heart-rates are classified into 4 Zones. Zone based workouts push you into periods where your heart beats faster than normal, in order to improve your cardiovascular strength.
Or you could even make it into a strength endurance workout by travelling on undulating terrain with a high gear ratio, low cadence ride.
It’s entirely up to you to design your rides at this point.
How To Choose A Bike With The Right Gears
For most people, a 3 speed or 7 speed bike will be most suitable. Another important consideration is that a gear bike with smaller gear ratios will be easy to ride and can be recommended for beginner cyclists. Fit riders can handle higher gear ratios and get more speed out of them too.
For a more nuanced understanding- choosing a bike with any given set of gears is easy if you understand the gear ratios that you want- anything that stays within that range will be ok.
You can easily find the gear ratio and other specs for each bike when you’re shopping. Just ask the store-keeper or google it.
How To Modify The Gears On Your Existing Bike
This section is for those of you who would rather modify your existing bike to bring in a wider range of gears rather than buy a new bike entirely.
To do so, you’ll need to look at changing the Chainset, Gear Cassette and (maybe) the Derailleur. Let’s look at them one by one:
Chainset. The standard Chainset configurations that you will generally find are:
- Standard: 53-39t . (This one is for pro riders- since front chainrings have higher no of teeth it gives more speed overall).
- Semi-compact: 52-36t (medium speed).
- Compact 50-34t (lower speeds as front chainrings have lower no of teeth- for beginner riders who are working on their fitness).
After reading all of the above configurations, you might be wondering what exactly do the numbers mean? Let me explain:
There are two types of Chainsets that you’ll see in the market, broadly- the first one has a single ring. The second type will have multiple rings (usually 2 or 3 rings). The number of teeth vary on each ring, and so each of the configurations given above describe the maximum-minimum range of the teeth across the rings.
Why do you need such variation? As you may intuitively understand having read the article till now, that it is simply done to vary the gear ratio and give the cyclist more options while riding.
Cassette. The Cassette is the hub of gears that you see at the rear of the bike. Here as well, they are described in the same format as Chainset, i.e: by giving the range of number of teeth on the biggest and lowest sprocket.
The lower the range, the more it is oriented to fit riders looking to ride at high speeds (exactly opposite the front Chainring/Chainset). The higher the range, the easier it will be for beginners.
Eg: 11-23t cassette is for fast riding while 11-32t cassette has a wider gear ratio, and has easier gears for beginner riders or those that ride hilly terrain often.
Bikes usually these days have a compact chainset- having 52 tooth outer chain ring and 34 tooth inner chainring. This is usually combined with a standard 11-28t cassette but can also be used with a 11-32t cassette which offers a wide variety of gear ratios.
Pro riders traditionally use a standard 53-39t chainset paired with a compact cassette (12-25t) for quicker rides.
If you want really low gears for climbing or touring, go for a triple chainset – it’ll have something like 26 teeth on the innermost chain for really low gear ratios. However, they can be a bit tricky to set up, use and maintain over time which is why most people prefer to get the wider range compact chainsets (50-34t)
Just note, however, that if you are going for a cassette with wider range of gears you likely will have to get a wider cage derailleur, for instance if you are upgrading from a 11-28t to a 11-32t cassette.
What is a Derailleur? The derailleur is what mechanically shifts the chain over the different gear sprockets of the bike. As the number of sprockets increase/become bigger, the derailleur needs to be upgraded to a wider size so that it can cover the larger sprockets. That will be an extra purchase costing approx. $30 or 22 GBP.
Also, you may not always be able to change the front chain rings as the cost can be prohibitive- however, if you are able to and wanting to do so, I found this really nice video that shows exactly how to change the cassette, derailleur as well as the front chainrings.
What Should Your Cycling Cadence Be?
It is generally recommended to maintain a cycling cadence within the 50-120 rpm range. 80-90 rpm is most optimal. The exact cadence will vary based on your level of fitness, experience of cycling and the terrain, as well.
If you already have a bike- how to upgrade the gears on your bike
Conclusion
For most people, getting a 3 speed or a 7 speed bike will cater to their entire range of requirements. However, to understand the finer details, you need to understand how bicycle gears work, gear ratios and how to modify them by playing around with the cassette, chainrings and derailleur.
I attempted to explain these topics in this article and I hope you found it useful. If you have any feedback regarding this post- please feel free to comment below. I promise to respond within 24 hours.