Wondering what “24 speed gears” means on a bike? Great!

Bikes, and especially gears and how to use them, can be incredibly confusing.

If you’ve got “24 speeds” on your bike, how do you change between them?

And, not only how do you change, but WHEN should you change between them?

What gears should you be using when you’re going up hills? Or, what about going down hills? Or just cruising along on flat pavement?

Gear shifters on a mountain bike or a hybrid bike can be easy to spot (they’re just near the brake levers in case you’re wondering!)

But what about on a road bike? Well on road bikes the gears don’t have there own separate shifters but instead are actually integrated into the brake levers.

Even “24 speed” is a bit of a misnomer, really. Why? Because, for each “speed” you could actually pedal along at the SAME speed on your bike.

Weird? Yeah. What it really means is that you have 24 gears to choose from when you’re cycling along. You can select any one of these gears at a particular moment and it will either make it easier or harder to pedal on the flat or slope that you’re traveling along right then.

So, yeah, bike gears are confusing.

My plan then is to explain what 24-speed bike gears are.

I’m going to go through how to change gears on the most popular types of bikes.

I’ll then go through some of the bike gears jargon that you need to know (think: “low gear” and “high gear”).

We’ll look at what gear you should use when you’re pedaling up hills and what gear you should change to for pedaling down the other side.

We’ll also touch on some specific gear combinations to avoid (known as “cross chaining”).

So let’s, ahem, switch it up a gear and dive into the detail.

What does 24 speed mean on a bike?

The first thing to note about a 24-speed bike is that you won’t actually see 24 separate gears on the bike.

Instead, what you actually get, is three cogs (known as “chain rings”) on the front of the drivetrain* by the pedals. With eight more cogs (known as the “cassette”) at the rear wheel hub.

*the “drivetrain” is the name for all the components on a bike which move you along i.e. pedals, cogs, chain and derailleurs.

You can see a side view of what this looks like below:

When you multiply 3 by 8 you get 24, which is the total number of gear combinations that you can get from all these cogs.

When you look at the drivetrain from the top (see below) you can get a better idea of how these all fit together: the different gear combinations are selected by moving the chain across so that it connects any two particular cogs together.

So, how do you change gears on a 24-speed bike?

How do you change gears on a 24-speed bike?

You can ride along on your bike without ever changing gears – the chain will connect a front cog (or chain ring) and a cog from the rear cassette.

However you’ll find that sometimes this will make pedaling very hard…

…and sometimes it will be too easy and you’ll find your legs spinning too fast.

Time for a change!

Shifting between gears is done by the gear shifters on the handlebars. These are connected via cables to the front and rear derailleurs.

The word “derailleur” comes from French and literally means to de-rail something. In this case, the thing that’s being derailed is the chain – pushed by the derailleur left or right onto a new cog.

The front derailleur is just above the chain rings at the crank. The rear derailleur is just below the cogs in the rear cassette.

Most modern bikes will have one of two types of gear shifter.

On mountain bikes, hybrid bikes, city bikes, commuter bikes, and many e-bikes, there will be two gear shifters. These are positioned near the brake levers and each gear shifter will have a pair of levers, one to shift up to a harder gear and one to shift down to an easier gear.

The gear shifter on the left of the handlebars operates the front derailleur and the right-hand shifter operates the rear derailleur.

Road bikes are somewhat different in that the gear shifting mechanism is integrated into the brake lever. Again, left brake adjusts the front derailleur and right brake adjusts the rear derailleur. The difference with road bike shifting is that the brake lever houses the controls for the gears. This may be part of the lever itself and/or with a separate button/lever in the same unit.

No matter the bike, when you’re changing gears you need to do this whilst you’re pedaling as the chain can only shift across between cogs when it is being moved around the entire drivetrain.

Which gear on a 24-speed bike is best for uphill?

The best gear for cycling uphill is a “low gear”, but what does this mean?

Take a look at the topdown diagram below.

Low gear combinations on a 24-speed bike are where the chain is on the smallest cog at the front – select this and you will be pedaling along in one of the lowest eight gears on your bike.

This will make pedaling up steep hills easier – your legs will be turning quite fast but won’t have to push as hard as they would in a higher gear.

On really steep inclines, you will want to shift to the lowest or bottom gear. This is where you have the chain on the smallest cog at the front and the largest cog at the back (the one closest to the rear wheel spokes).

This gear is also known as “1st gear”.

The purple chain on the diagram shows this bottom gear combination.

Remember, when shifting gears, it’s best to do one at a time as you pedal, rather than attempt to jump through multiple gears at once. This can cause the chain to get caught or come off.

Which gear on a 24-speed bike is best for flat or downhill?

Once you’ve got to the top of the hill and are either going to be cycling along flat ground, or going downhill, it’s time to shift from the lower gears up into higher gears.

Higher gears allow you to move along further for each pedal revolution.

The diagram below shows what high gears look like from above.

To get into your highest group of eight gears, you need to shift the left gear lever so that the chain is on the largest chain ring (the one closest to the right pedal).

For especially steep descents, or when you’re cruising along on flat road, then you can choose your “top gear” or highest gear. This is where your chain is on the biggest cog at the front and the smallest cog at the back wheel.

This would be “24th gear”, though it’s generally just called top gear instead.

You can see this combination in the diagram.

Remember that, because changing gears takes time, it’s important to look ahead and see how the incline is going to be changing. If you’re in your lowest gear coming to the bottom of a downhill, and don’t take account of a steep uphill just ahead, then you will have to do some rapid gear changing (from high gear to low gear) or you’ll end up having to get off and push your bike up!

Caution! Avoid cross-chaining

When you’re shifting between gears, it’s worth being aware that there are two gear combinations that it’s good to avoid.

You can see these in the diagrams below.

The first is where you have the chain on the biggest cog at the front and the biggest cog at the back (“17th gear”).

The second is where you have the chain on the smallest cog at the front and the smallest cog at the back (“8th gear”).

Why?

Well each of these combinations forces the chain to be pulled sideways.

Chains don’t really like this and you’ll likely find that they respond by clanking quite noisily. Cycle in a cross-chain gear combination for a long time and you’ll also get more wear to the chain meaning that you’ll have to replace it sooner.

With 24 gears at your disposal, there’s no need for cross-chaining so just pick another gear that’s close but keeps the chain running straighter.

Conclusion

Having lots of gears on a bike can sound great, but it can also be very confusing when you’re trying to work out how to change between them and which gear you should be in at any particular moment.

There are a few useful rules of thumb to remember:

The Right gear shifter is for the Rear derailleur.

With the chain on the smallest cog at the front, the pedalling will be easier (useful on uphills).

With the chain on the biggest cog at the front, you’ll be able to pedal faster on flat roads and down hills.