A Complete Idiot’s Guide to Bicycle Gears & Shifting
Moving from a one speed bicycle to one with multiple gears is a big step. Not only do you have to learn how to shift the gears, you also have to learn what gears to use, and figure out when to shift into which gear!
I was reminding of this when I received this plea for help…
I have a 28 speed and knowing when to shift, and what gear to shift to is driving me nuts! I need an idiots’ guide to shifting! Help!!!
Well, you got it! Here is the “Complete Idiot’s Guide to Bicycle Gears & Shifting” to explain everything a beginner needs to know about using a multi-speed bicycle.
Introduction to Gears and Terminology
Ever since bicycles came with more than one sprocket on the front and back, they were usually referred to as the number of gear combinations that were offered. For example, a road bike with two chainrings up front and a five-speed freewheel on the back was a “10 speed,” since the five rear sprockets could be matched with either of the two front chainrings. (2×5=10, it’s just simple math.)
But once you learn more about gearing, you’ll see that that is actually a confusing way to describe things. So to start things off, let’s get the terminology straightened out:
The front sprockets that are attached to the crankarm are called chainrings. If you have two chainrings (a big ring and a little ring,) that setup is called a “double.” If you have three chainrings (big, middle, and little,) you have a “triple” chainring setup.
The gear cluster on the rear wheel is either a freewheel or a cassette. If your bike has five gears on the back, it probably has a freewheel. If your bike has eight to ten gears on the back, it has a cassette. Each ring on the cassette is referred to as a cog. (The difference between a freewheel and a cassette makes no difference in this article, so don’t worry about that.)
For this article, our example bicycle will be a modern mountain bike with three chainrings and an 8-speed cassette. Some people would call this a “24 speed,” but most avid cyclists and bike mechanics refer to this simply as an “8 speed.”
Discover How the Shifters and Derailleurs Work
Having gears won’t do you a bit of good without understanding how the shifting works, so here’s a look at that…
Shifting starts at the shift levers, which are usually located on the handlebar beside the grips. When you move one of the shift levers, a cable pulls or releases one of the derailleurs which moves the chain from one gear to another.
In typical setups, the left shifter is matched to the front derailleur (so it shifts between the chainrings.) The right shifter is matched to the rear derailleur (which shifts between the cogs on the cassette.)
Let’s talk about the shift levers (“shifters”) first…
Each shifter will have numbers on it to indicate which gear you are in (this is the gear indicator.) In this example, our left shifter shows numbers 1-3, while our right shifter shows 1-8.
The lower the number, the easier the gear is. So if both the gear indicators show “1” then you are in the easiest gear the bike offers. If the left shifter is at 3 and the right is at 8, then you are in the hardest gear on the bike.
On the left shifter, you will see numbers to indicate which gear you are in – 1, 2, or 3. The number 1 corresponds to the little ring, 2 is the middle ring, and 3 is the big ring. For the front chainrings, bigger chainrings equal a harder gear.
On the right shifter, the numbers 1-8 are all there. The number 1 corresponds to the biggest cog, while number 8 corresponds to the smallest cog. When it comes to the cassette, bigger cogs equal an easier gear.
Let’s not forget the derailleurs…
This is the easy part though, because once you shift the levers, the shifter cable will relay your instructions to the derailleur.
What happens when you shift is the derailleur cage (which the chain runs through) will move to either side. Let’s say you shifted the front shifter to an easier gear. The front derailleur will move to the left, thereby “derailing” the chain onto the smaller chainring. As long as the derailleurs are adjusted properly, they will do their job just like that, and you can concentrate on shifting!
Types of Shifters
Before moving on to shifting and gear selection, let’s take a quick look at the various types of shifters out there. (We’ll concentrate on the three types that are most common on modern bicycles.)
First, grip shift. With this type of shifting, there are no levers. You shift by twisting a section of the grip forward or backward, depending on whether you want a harder or easier gear. It is very simple to get the hang of it, so it comes on most mountain bikes in the $100-300 price range.
Note: Pictures in this article are grip shifters.
Second, trigger shifters. These are also very common on mountain bikes, but also on road bikes, in different form. (They are usually called Shimano RapidFire or Shimano STI.)
In this case, you’ll have two “triggers” beside each handlebar grip. There are two triggers on each shifter because the triggers only move in one direction.
On the left trigger shifter, the small trigger shifts to a smaller chainring, for an easier gear. The bigger shifter will shift up to a bigger chainring, for a harder gear.
On the right trigger shifter, the little trigger shifts to a smaller cog, which gives you a harder gear. The bigger shifter will shift up to a bigger cog, which gives you an easier gear.
(Trigger shifters do sound complicated, but they aren’t a problem once you practice with them a little bit.)
Basic Fundamentals of Gear Selection
Now you know the basics of shifters and derailleurs, so let’s move on to choosing which gears to use.
The most important thing here is that there is no such thing as the “right” gear. Choosing a gear depends on numerous factors, not the least of which is comfort. Really, gearing is personal preference, so you and your friends will probably ride in different gears, even if you are going the same speed on the same road.
However, one thing to consider is your cadence. Cadence is another word for your pedaling speed (basically, how fast your legs spin in circles.) This is measured in RPM, or “revolutions per minute.”
Cadence is important because it directly impacts your comfort level. Pedaling at a slow cadence usually means you are using too hard of a gear, and your leg muscles will tire out quickly. It can also hurt your knees. A good rule of thumb is to keep your cadence fairly high, usually in the range of 75-90 RPM. (Here is how to count your cadence.)
But aside from comfort and cadence, the middle of your gear range is a good starting point. Say you’re starting out on a flat road at an easy to moderate pace (on the “24 speed” bike.) You should be in your middle ring (2) up front, and roughly your fourth largest cog (4) in the rear.
(A good moderate gear is pictured to the left.)
To make small adjustments to your speed, you will want to shift the rear derailleur. If you need to go a little faster, shift to a smaller cog (5, 6, or 7.) If you want to ease up on the pace, shift to a bigger cog (1, 2, or 3.)
But if you come to a steep hill climb, or a long downhill, you will want to make a big jump in your gearing. So instead of shifting the rear derailleur, you’ll shift the front derailleur first.
An Example of Proper Shifting
Here is an example of how you might shift gears while out on a bike ride. At the start, you are currently in the middle ring and one of the middle cogs. Then…
Let’s say you’re coming up to a steep hill climb. You will shift to the small chainring (1) up front. If that gear isn’t easy enough, then you will shift the rear derailleur to a big cog (1, 2, or 3.)
Once you hit the top of the hill and the road flattens, you can go ahead and shift the rear derailleur back to a slightly smaller cog, getting to number 3 or 4. Then it’s time to shift the front derailleur back to the middle ring (2.) If the road remains flat, you could stay in that gear or shift the rear derailleur once again, going to 5 or even 6.
But then when you hit the downhill, you need a big change in gears, so you’ll shift the front derailleur up to the big ring (3.) That should give you a good gear. If you need a harder gear though, you can shift the rear derailleur to the smallest cogs, 7 and 8.
As the road changes, keep repeating the process.
Just remember: Shifting the left shifter makes a big impact, and shifting the right shifter is to fine tune your gear selection. You will shift the right shifter (for the rear derailleur) much more often than the left shifter.
What to Watch Out For
If you followed along through that gradual shifting process, you might have noticed we only ran through about 12 different gear combinations, when the bike actually offers 24. Why?
Well, your “24 speed” bike isn’t meant to use all the gears. Certain gear combinations are very rough and sometimes dangerous.
See, you need to keep your chain running in a straight line for the bike to ride smoothly. You do that by using certain combinations of gears and avoiding others. (A straight chain line is pictured in a previous section.)
For example, when you are in the small chainring, you will want to use the biggest four cogs, numbers 1-4. When you are in the middle chainring, you can use most of the cogs, but I would stick to numbers 1-6. When you are in the big chainring, you should stick with the smallest cogs, 6-8. This will keep your chain in a fairly straight line.
If you use extreme gear combinations, such as the small ring and the smallest cog or the big ring and the biggest cog, that’s called cross chaining. This puts the chain at too much of an angle, which makes the chain wear out extra fast. (You’ll usually hear some sort of grinding noise coming from the chain if you do this.) It also makes it more likely that the chain will fall off the bike.
When to Shift (A Few More Pointers)
To shift smoothly and easily and keep a constant, comfortable cadence, you want to anticipate your shifts. It’s just like the example above.
If you are approaching a steep hill climb, you want to shift down to an easier gear before you need to. The steeper the hill, the more gears you will want to shift down.
If you wait until you can barely turn the pedals before shifting down, you’ll have a heck of a painful time trying to climb the hill!
Likewise, if you are going downhill, gradually shift up as you gain more speed. Don’t wait until your legs are spinning around like crazy!
Another thing to anticipate is starting up after you come to a stop. If you are riding in a big gear, you will want to shift down as you slow down and come to a stop. If you stop while you’re still in a big gear, it will be very hard to get started again!
But if you anticipate that and shift to a low gear before stopping, you will be able to start easily.
Proper Shifting Technique
There is more to shifting than just twisting some levers. Shifting requires precise coordination between your hands and feet; the better you coordinate your movements, the smoother your shifts will be.
The basic principle here is that you have to be pedaling for the bike to shift. The chain needs to be moving forward for the derailleurs to do their job, so always pedal when shifting.
But there is a little trick to it. You need to be pedaling lightly and softly for the bike to shift smoothly. It’s called “soft pedaling.”
If you are pedaling too forcefully, your leg power will override the derailleurs and there will be no shifting, just grinding noises! (Think about it, your legs are big and muscular, and the derailleurs and chain are just little pieces of metal.)
So here’s how to shift:
As you move the shifter with your hand, simultaneously ease up on your pedaling for one stroke. You should hear and feel the shift complete smoothly. Then you can resume pedaling with full force. Don’t worry, you only ease up for a second, so you won’t lose speed just from soft pedaling.
That’s all there is to it. Most people I see that have trouble shifting simply need to try soft pedaling. It is a common misconception that you need to pedal hard and fast to get a shift to complete. Proper shifting actually calls for the opposite approach!
Just get out there and practice…
Getting Started (Practice Makes Perfect)
Now that you know what to do, it’s time to do it. But it won’t hurt to do a few practice runs first!
The first thing I would do is run through the gears by hand. Just prop the bike up so the rear wheel is off the ground (if you don’t have a repair stand, just hang the bike on a tree branch or something,) and then shift through the gears while pedaling with your other hand.
Once you see it in action, head out to an empty parking lot and ride in circles. You just want to get the “feel” for shifting so that it becomes second nature. You want to be able to go ride and pay attention to your surroundings, without needing to look down at the shifters.
Don’t feel bad if it takes a while, we’ve all been there at one point! It’s not easy to go from one speed to dealing with 24 or 27!
(Think of it like driving a manual transmission car – most people don’t know how to do that!)