Unless all you’re ever going to do is cycle up and down on flat roads, contemplating the most suitable of gears to sustain your pedalling speed/cadence and level of effort over a varied terrain is one of the most important decisions you will have to make while setting up your bike. As daunting as ‘technical gear terms’ might seem to you, cycling around without a thorough understanding of how bicycle gear works is undoubtedly a more difficult task. Making the move from a one-speed bicycle to one with multiple gears means embracing a whole lot of new information like learning what bike gear to use, how to shift the gears and even when to shift to which gear….Simply put, the right gears will not only make your cycling experience a lot more enjoyable but will also make you faster and enable you to cycle for a longer time period without getting tired.
So various component manufacturers have gone to extreme lengths to introduce us to technology that allows a bicycle to have up to 33 gears. What will help you to choose the most suitable gearing is figuring out the most elementary and basic knowledge of the principles of how gears function, the effect that the variation in sizes of front chainrings and rear cassette sprockets will have on your pedalling and information of the like.
- Why have Gears
- Terminology and Key Bits of a Bicycle Gearing System
- Understanding Gear Ratios
- Types of Shifters
- How do the Shifters and Derailleurs Work
- What is the Best Gear To Be in?
- Proper Shifting Technique
- How to Use Bike Gears on Different Terrains
- Bike Gear Shifting Tips
- What To Avoid when Changing Bike Gears
- Basic Drivetrain Maintenance
Why have Gears
The purpose of having gears is to permit the sustenance of a congenial pedalling speed or cadence, no matter what the terrain or gradient be. There are two gears- high and low gear.
A high gear is favorable for speed riding, where the largest front chainring size is combined with the sprocket. Now you might think what is a low gear on a bike? Well, it is just the opposite of high gear and is used on steep terrains and roads. A combination of smallest front chainring size with largest rear cog or sprocket.
However, to clarify, do not live with the misconception that a bike sporting a lot of gears, will mean an automatic increase in the level of its speed. If a bike features 30 or more gears, it in no way indicates its capabilities of break neck speed, in comparison to a single geared bike, if you assume similar ratios.
People who would choose to ride single speed bikes over multi geared ones, will still own a bike which sports a gear, determined none the less by the size of the front chainring and rear cog. These kind of bikes are favoured by commuters living in flat areas since they require little maintenance. Some racers too prefer single speed bikes when they want to drop weight and cut down on any extra complication coming from the shifting process.
Terminology and Key Bits of a Bicycle Gearing System
Before understanding the bike gear shifting technique, let's learn about the parts of the bicycle:
This term encompasses all of the moving parts which connect the crank to the rear wheel, thereby enabling it its movement. Drivetrain would include the chainrings, the cassette, and the chain.
Chainrings consist of either one or more sprockets. This is attached to the cranks, to which the pedals are affixed. A chainring is made up of evenly spaced teeth which engage the chain as it passes over, to transfer the power or the energy from the pedals to the wheel.
This is probably the most easily identifiable part – a cycle chain is what engages with the teeth of the chainring. Pedalling causes the chainring to rotate, and move the chain, hence causing the wheels to turn and the bike to move forward.
A sprocket, cog or a sprocket-wheel is a profiled wheel with teeth which interlock with the chain.
This is another term for the group of rear sprockets but technically refers to the older, screw-on freewheel.
This is a cluster of sprockets. It is mostly located on the rear hub of the bike slotting onto a free hub body. This is firmly held in place with a threaded cassette lock ring.
There are two kinds - Front and rear derailleurs. These perform the hard task of transferring the chain from one sprocket or chainring to the other. The front derailleur is known to simply move the chain from side to side. The rear derailleur, however, is dual purposed. It positions the chain onto the chosen sprocket. It is also fitted with a spring which means that it maintains the right level of the tension in the chain as you move between gears.
These are the controls which are used to change the gears. Usually, they are located on the handlebars, but if you are going old school, you might find them attached to either side of the frame’s down tube. The gear shifters are connected to the derailleurs by gear cables or in the case of the new electronic systems, electric wires.
The pedalling speed which is measured by the number of revolutions the crank makes per minute — expressed in RPM.
Understanding Gear Ratios
Gear ratio, in its most straightforward calculation, is a function of the number of teeth on the front chainrings, compared to the rear cogs. It describes the relationship between sprockets and chainrings. Divide the front number of teeth by the rear numbers, will give you a number. The higher the number, the harder the effort per turn of the wheels. The smaller the number, the lower effort per turn.
Consider turning the front chainring once with a pedal stroke which will turn the rear cog four times, it means that you’ll travel four times the circumference of your wheel in return for that effort. In case your single pedal stroke only turns the rear wheel twice, then that would give you a gear ration of two. If this sounds confusing, then you can use the bicycle gear ratio chart and get details about your gear ratios.
Types of Shifters
Shifting gears on a bicycle will help the rider adjust to the difficulty of pedalling and the pedal-to-wheel rotation ratio. This will further enable the cyclist to be more effective while riding over paths of varying difficulties and inclines. There are different types of shifting systems that have been developed keeping in mind the needs of riders and depending on the type of bike they are riding.
Grip shift, also called twist shift are most commonly featured on mountain bikes, and they can also be used on other bikes with straight handlebars. On this type of shifting, levers aren’t present. So, you shift by twisting a section of the grip either forward or backward, as per whether you would like a harder or easier gear.
Trigger shifters also known as ‘rapidfire’ shifters, are located below the handlebar. In order to shift, the rider needs to use a thumb button when he wants to shift to larger sprockets. There is the small index-finger operated ‘trigger’ which is used to downshift. Trigger shifters are common on mountain bikes but can also be found on road bikes, however in a different form.
How do the Shifters and Derailleurs Work
Previously, during in the good old days where gears hadn’t really undergone much change or progress, the process to change a gear with a derailleur would mean deciding on how far off to pull a lever so that the chain moves between the cogs, causing what was known as ‘friction shift’.
Of late, most shifters are ‘indexed,’ so you ‘click’ to change gears. Now what happens is that when you move your shifter, it pulls on an inner cable which is sliding below resistance via an exterior cable. This in turn forces the derailleur to change shape, thereby pushing a chain sideways and on to a different sprocket.
On a derailleur equipped bicycle you will find two sets of gears.
- The Rear Derailleur / RHS Shifter is located on the right of your handlebars. This gear employs the rear derailleur. The rear derailleur is what moves the chain from one sprocket to another on your rear wheel. This is the most frequently used shifter.
- The Front Derailleur / LHS Shifter. You will be equipped with a LHS shifter if you have two or more chainrings. This shifter is what will move the chain between the multiple chainrings using the front derailleur. How the front derailleur functions is that it utilizes two plates on either side of the chain in order to push it sideways. Rest of the work is carried out by the ‘hook’ effect of the cogs on the chainring and the rotation of the chain and chainset. The ‘hook’ effect essentially is picking up the chain and engaging it on the new cog.
Once you achieve the confidence to operate them, your instinct will tell you which gear you are in. Rather than just pushing a button, relate to the comprehension of when and how to wield your shifters and actually aim to ‘feel’ your gears change.
What is the Best Gear To Be in?
The most appropriate gear to be in, would be a gear that will allow you to have a good balanced and stable cadence without having the feeling that you are either pedalling too hard or too gently. Should you select a gear that is too high for the conditions, it will leave you with a slower cadence. Pedalling at a faster pace than your ideal speed will definitely generate that extra burst of speed, but it will also tire you out too soon. Similarly, pedalling slower than your quintessential cadence will be wasteful of energy. Also, there are the dangers of muscle strains and joint damage to the knees and hips to consider.
As a rule of thumb, the goal should be to maintain a fairly high cadence, customarily in the range of 75-90 RPM.
Proper Shifting Technique
How you shift gears on your bike can make a difference in the lifespan of your drivetrain and in the feel of your ride. An important rule in shifting is to reduce the pressure on the pedals during shifts. Most modern drivetrains will shift regardless of pedal pressure, but easing up a bit on the pedal pressure, will make the shifts smoother and also your chain, cogs and chainrings will last longer.
The act of shifting is the precise coordination between your hands and feet; the better the coordination, the smoother the shift. The basic principle is that you have to be pedalling for the bike to shift, and we again stress on applying less pressure on the pedals. For the derailleurs to be able to do their job, the chain needs to be moving forward, hence always keep up the pedalling when shifting.
So here’s how to shift:
For small changes, shift the chain between the rear cassette cogs. For big changes, shift between the front chainrings. It’s recommended to only use one shifter or else you might run up against issues such as jamming the chain, dropping it off the cassette or the chainrings, or even mis-shift. When you are riding on flat roads it’s passable, shifting through several gears at a time, in fact, it might even be easy if you are doing it regularly. But if you are on a hill, shift one gear at a time, simultaneously relieving the pedals of momentary pressure whilst shifting.
Try to foresee the terrain, so that you are able to make the shift right before you begin the ascent and not halfway up when you’ve nearly stopped with maximum pressure on the pedals. There are different types of bike pedals that will let you ride smoothly on the terrains.
When you do shift, do not cross chain. This means putting your chain on conflicting ends of the front cogs and the rear cassette simultaneously. If you cross chain you are running the risk of dropping or even breaking your chain….which is either ways not good news.
When you move the shifter with your hand, at the same time for that split second, ease up on your pedalling for that one stroke. You should be able to hear the click and feel the shift complete smoothly. Post this, you can return to pedalling with full force. Since you are only easing up for a second there’s no chance of you loosing speed just from soft pedalling. Most people struggle with the concept of soft pedalling, which leads to them having trouble shifting. Proper shifting actually doesn’t require hard and aggressive pedalling.
How to Use Bike Gears on Different Terrains
This quick guide on how to use bike gears, will let you ride like a boss on any terrains:
How To Use Bike Gears on a Hill
Use the small or middle chainring upfront and the bigger gears in the back. What you will want to do is switch in to these gears as early as you approach the climb, which will then allow you to climb the hill slowly and with less effort.
Lower gears or smaller chainrings are known to make climbing hills easier, which means you can maintain your cadence or keep it homogenous in hilly terrains or over greater distances.
How To Use Bike Gears on a Flat
Use the middle front chainring and the middle or small gears in the back. Centre your attention on only minor adjustments with your back gear.
How To Use Bike Gears while Descending
Use the large front chainring and the middle or small gears in the back.
Bike Gear Shifting Tips
A few things to keep in mind when you are shifting bike gears are the following -
- When you are upshifting, at a time only shift one cog. Pause till you feel the spin-off of that gear before you shift again. Note to remember – the shifter for the rear derailleur which handles your upshifting is located at your right hand.
- When you are downshifting, always make the shift prior to encountering an obviously discernible reduction in the momentum. As soon as you feel an increase in pitch, downshift.
- Upon arriving at significant terrain changes, shift chainrings, either up or down. When you start on a descent or you reach the foot of a big hill, are indicators of the most natural times of shifting from one chainring to another. Note to remember – the shifter for the front derailleur is located at your left hand.
What To Avoid when Changing Bike Gears
Cross chaining occurs when the chain is on a big slant. The chain should not go on the big ring up front and the big ring on the back at the same time. It should also not go on the small ring upfront and the small ring in the back simultaneously. Cross chaining will wreck your chain, decrease your efficiency and also provide you with lesser options when you’re trying to find new gear.
How many gears do you need for a road bike?
Nearly all road bikes will feature at least 18 gears, but they could include up to 30 gears in number, in fact even more, contingent to the number of chainrings and cogs.
As for cranksets there are the two kinds: Standard Cranksets and Compact Cranksets
Standard Cranksets for road bikes have two chainrings, while compact cranksets come with two chainrings that are comparatively smaller than those on a standard crankset, which in turn makes it easier to pedal while climbing hills. A commonality with a standard crankset is a 53 tooth large chainring and a 39 tooth small ring, while in the case of a compact crankset is a 50 tooth ring and a 34 tooth ring, with also varied options also available.
How do road bike gear shifters work?
There are three pointers to keep in mind:
- The shifters are built into the brake levers; you push them sideways to shift.
- They are not numbered.
- The left shifter has a trim feature for the front derailleur.
The left shifter is for making big changes and the right for fine tuning. As mentioned otherwise too, the left and right shifters work opposite of each other. As the shifters aren’t numbered, you will have to look down to see which chainring on the front and which cog in the rear the chain is on in order to determine what gear you're in.
Basic Drivetrain Maintenance
In order to keep your drivetrain running smoothly, clean it after you ride and lubricate the chain. Whilst cleaning your chain, always check your cables - if they are frayed or rusty, go in for a replacement. At least once a year, have a professional remove your cassette, chain and chainrings to clean them in a parts cleaner.
Gears are simply components that are used to transmit power from one part of a machine to another. Like in the case of bicycles, the gears with the help of a chain take power from the pedals to the back wheel. Learning to properly shift gears will increase your speed, make your ride much more comfortable all the while increasing your endurance during longer rides. While learning how to shift gears isn’t knowledge that might seem that basic, however, grasping the tactics of efficient gear shifting is something even a novice cyclist can work on. While gears are quite a blessing in disguise, it’s the shifting that brings on the fear, but remember, it’s simply science in action!