A road bike groupset is the collection of components that make you stop and go — in other words, the drivetrain, shifters and brakes. Plenty of companies make bike components, but the market is dominated by three giants: Shimano, SRAM and Campagnolo. Let's look at each of them in turn…
Despite the differences between the brands, the components all do the same job, even if there are some subtle variations in how they approach their specific tasks. We'll start this buyer's guide by explaining the different groupsets available, then go into greater detail on the individual components, and how they differ between brands. We finish by explaining the benefits of the more expensive groupsets, and flag up some compatibility issues.
Road bike groupset hierarchies
Shimano is the oldest and most widely used of the three main brands. It began life in Japan in 1921 when Shozaburo Shimano decided to start making freewheels in a rented corner of a demolished celluloid factory. Fast-forward to today, and it's become so successful that Shimano now accounts for half of the global bike components industry.
Entry level Shimano groupsets
The range starts with the budget-priced Claris, which is usually found on the most affordable bikes available. Claris is an 8-speed system (eight gears at the rear) combined with either a double or triple crankset.
Next is Sora, which can also be found on entry-level bikes and is a 9-speed system available in either standard double cranksets or a wide-range triple.
Next up is Tiagra, a 10-speed group that shares some of the designs and technology of the higher-priced 105 system, and benefits from the trickle-down of technology from the higher end group, such as four-arm cranksets.
Performance Shimano groupsets
Shimano 105 is the most affordable performance-focused groupset from the Japanese firm, and comes on many mid-market road bikes. This 11-speed group is considered by many riders to be the best combination of performance, durability and value.
Shimano Ultegra sits one below the professional-level Dura-Ace. This 11-speed group has the same design features as the range topping Dura-Ace and offers all the performance most riders will ever need, but is 258g heavier than Dura-Ace.
Pro-level Shimano groupsets
Dura-Ace is the pinnacle of Shimano's range. It offers 11-speed gearing and combines top-end design with lightweight materials such as high-grade alloys, carbon fibre, and titanium.
Shimano Di2 electronic shifting
Shimano also offers both Ultegra and Dura-Ace groupsets with electronically operated Di2 shifting. The Di2 groupsets share the same crankset, cassette, chain and brakes of the respective mechanical groupset (so Ultegra Di2 has the same as Ultegra).
American firm SRAM is the new boy on the block, appearing during the mountain biking boom of the late ’80s and establishing itself on the back of its lightweight GripShift shifters.
SRAM's road groupset range comprises four main groups – Apex, Rival, Force, and Red (in ascending order of price). SRAM groupsets are the lightest weight on the market at each price point.
Entry level SRAM groupsets
The Apex group is a 10-speed group that features SRAM's WiFli system. WiFli offers a very wide gear range (between 11 and 32 teeth) for the rear cassette. That allows SRAM to offer the wide range of gears usually found by using a triple front chainring setup without the extra weight and complexity of a triple.
SRAM also offers its Apex group in 1x11 gearing – that is to say, just one chainring at the front, and 11 gears at the rear.
Performance SRAM groupsets
Next up the line is Rival, which can also use a wide range WiFli rear derailleur and cassette, but is made from lighter materials than Apex. Rival is by far the most popular SRAM drivetrain on road bikes, and is 11-speed. It can be found with a more common two chainrings at the front (2x11), or just one (1x11).
Going up in price to Ultegra-level, SRAM's Force group uses lightweight materials such as high-grade alloys and carbon fibre to be a very competitive gear setup. Like Rival, it's an 11-speed groupset that can be configured with a two chainrings at the front for more gearing range, or one chainring at the front for simplicity.
Pro-level SRAM groupsets
SRAM's Red group is a proven pro-level 11-speed groupset, and has been ridden to victory in the Tour de France on numerous occasions. It is a direct competitor for Shimano Dura-Ace.
SRAM Red components use super-light materials throughout, including high-grade alloys, plenty of carbon-fibre, titanium and even ceramic bearings. SRAM Red is also available in a WiFli option, allowing for an ultra-wide range of gears. Of all the top-of-the-range groups, SRAM Red is the lightest on the market at 1,747g.
SRAM eTap electronic shifting
The American company started offering electronic shifting for its Red groupset in 2015. Known as eTap, this is the only wireless option available from the three main component brands.
Italy’s Campagnolo arrived in 1933, after founder Tullio Campagnolo’s frustrated attempts to remove a rear wheel during a race inspired him to design the quick-release lever. It is perhaps the most storied of cycling brands thanks to its association with so many of the sport’s greats — Fausto Coppi, Gino Bartali, Jacques Anquetil, Eddy Merckx, Bernard Hinault, Miguel Indurain… As such, Campagnolo is often the choice of dyed-in-the-wool aficionados and bike collectors.
Entry level Campagnolo groupsets
Campagnolo groupsets start higher up the overall hierarchy than the competition, so you're unlikely to find the Italian brand on bikes that cost less than £800 / $1,000 / AU$1,400.
The entry-level Veloce groupsets sits around the same area as Shimano Tiagra or 105, or SRAM Rival. It's a 10-speed group and is made from lightweight alloys.
Athena is a direct rival for Shimano Ultegra and SRAM Force. It includes carbon composite components and the technical advances of Campagnolo's top-end groupsets, and comes in either 2x11 or 3x11.
Performance Campagnolo groupsets
Potenza launched in 2016 as another rival for Ultegra. It combines higher-end features like a four-arm crankset with the dropped inner shift lever found on Veloce and Athena groupsets, which is easier to reach from the drops but limits you to one downshift. It comes in 2x11 gearing.
Sitting just below the range-topping Campagnolo Record family is the 11-speed Chorus. It uses light alloys, carbon fibre and titanium in its construction, and sits between Shimano Ultegra and Dura-Ace, or SRAM Force and SRAM Red.
Pro-level Campagnolo groupsets
Campagnolo Record is the flagship groupset from the Italian brand. It uses high grade carbon fibre in its construction combined with lightweight alloys and titanium. 11-speed Record is found on the highest-priced bikes – £3,000 / $3,800 / AU$5,000 or above.
Campagnolo also offers an even higher-level groupset in the form of Super Record. While essentially the same as Record, it uses even fancier materials to lighten and enhance each and every part. It can be considered an 'hors catégorie', above anything offered by Shimano or SRAM, and is only usually found on the most expensive pro-level road machines.
Electronic Campagnolo EPS groupsets
Campagnolo also offers a range of electronic groupsets under the name EPS (short for Electronic Power Shift). It starts with Chorus EPS, which, like Shimano, is driven by electric motors and battery power – the batteries can either be externally mounted or hidden with the seat post or seat tube.
Record EPS uses lighter materials to reduce overall weight, and Super-Record EPS refines everything further. Super Record EPS is the market’s money-no-object groupset. Just like Shimano, the EPS groupsets shares the same crankset, cassette, chain and brakes of the respective mechanical groupset (so Record EPS is the same as Record).
Road bike groupset components
Right, now that we know how the different groupsets stack up, let's look at the individual components to be found in a groupset. We'll explain the key differences between the different brands, and what high-end features to look out for.
Crankset / chainset
The crankset is the largest part of any groupset and is comprised of the chain rings, the cranks, and, in most cases these days, the spindle that links the two crank arms together.
Cranksets are grouped into three categories based on the number of chain rings used: double (the most common), single (popular in mountain biking) and triple (an older standard).
Double crankset variations
- The standard double crankset is most commonly used by pro riders, and consists of a 53t big ring and 39t small ring.
- The semi-compact crankset – or pro-compact – is 52/36t. This gives you a slightly easier climbing gear while still retaining big top gear. It is a popular option among competitive amateur riders.
- The compact crankset is 50/34t. It has become very popular with thanks to its combination of easy gearing and low weight.
- The super-compact crankset offers an even lower gear range on double chainrings (typically 48t/32t). These are becoming popular with gravel riders and bikepackers who want low, closely spaced gearing
- The triple is an older type commonly seen on vintage road bikes and touring bikes. It offers a wide range of gears, but at a weight penalty. It combines a 50t outer ring, a 39t middle ring and an inner ring that has just 30 teeth. It is popular with touring cyclists who value a super-small 'granny ring' when loaded down with panniers.
- The single-ring crankset – also known as 1x (pronounced 'one-by') – has only one chainring. To compensate for the loss of the smaller, inner ring, they are often matched with a wider-range cassette.
Road bike shifters explained
For the most part, modern road bikes use dual-action shifters that incorporate the gear levers into the brake levers. Each brand has its own spin on the concept, so how you shift gears on a Shimano-equipped bike is slightly different to how you shift on a Campagnolo- or SRAM-equipped bike.
You've probably heard about electronic shifting too – this is found on the upper-tier, more expensive groupsets from all three brands, and still relies on paddles built into the brake levers, but uses small servomotors in the derailleurs to make them move. Electronic drivetrains offer consistently precise shifting and lower maintenance than a mechanically actuated drivetrain.
Shimano road drivetrain shifting explained
Shimano Total Integration (STI) uses brake levers that are split in two, with a paddle sitting behind the brake lever. The right brake lever/paddle combo controls the rear derailleur, and the one on the left controls the front derailleur.
If you swing the paddle of the right shifter inwards, the chain will shift down the cassette to a smaller sprocket. Swing both paddle and brake lever inwards and you shift the chain back up the cassette to a bigger sprocket. The actions are the same for the left-hand shifter, except it shifts the chain from one ring to the other.
Shimano's electronic system – known as Di2 – works in the same way to shift gears as its mechanical equivalent. It can also be programmed to switch which shifter changes which derailleur, or how many cogs you want to shift if you hold the shifter down, and how fast.
SRAM road drivetrain shifting explained
SRAM DoubleTap also uses two-part brake levers, but only the paddles on the rear of the brake lever are needed to shift gears.
If you push the paddle on the right lever inwards a little, until you hear a click, the chain will shift down one sprocket. But if you keep pushing the paddle inwards you’ll hear a second click and shift the chain up one sprocket. The left-hand shifter controls the front mech in the same way.
SRAM's electronic system – known as eTap – works in a slightly different way. To shift up a gear on the cassette, you tap the paddle behind the right-hand brake lever; to shift down a gear on the cassette, you tap the paddle behind the left-hand brake lever. To switch chainrings, you tap both together.
Campagnolo road drivetrain shifting explained
The Campagnolo Ergopower system uses split brake levers with shifter paddles on the back similar to SRAM and Shimano, but they’re joined by an extra button on the thumb side of each of the hoods.
To shift down the cassette, press the thumb button on the right shifter and to shift up it you swing the paddle behind the brake lever inwards. The same actions on the left shifter take care of shifting between chainrings.
Campagnolo's electronic system – known as EPS – works in the same way as its mechanical equivalent, though it can be programmed to suit your needs. The MyCampy smartphone app also helps you self-diagnose any problems with your shifting.
The complications don’t end with the various shift actions and whether they’re mechanically or electronically actuated. The variety of brakes used on road bikes has also grown more complex in the last few years.
In the past, cable-operated, calliper rim brakes were the only type of stoppers used on road bikes. But recent years have seen road bike braking options expand to take in direct-mount rim callipers, hydraulic rim callipers, cable-operated disc brakes and hydraulic disc brakes.
DIscs provide superior braking in wet conditions for only a marginal weight penalty, and are fast winning fans.
Which type of brake is best for you is dependent on a number of factors. To learn more about road disc brakes, check out our explainer here.
As of January 2017, Shimano has rim calliper brakes, hydraulic disc brakes and mechanical disc brakes available for road cyclists, at various groupset levels. It speaks volumes that the company's new top-end Dura-Ace groupset gets hydraulic disc brakes – Shimano clearly sees these as the future.
SRAM currently has both mechanical and hydraulic rim brakes, plus hydraulic and mechanical disc brakes. The later is offered via its sister brand, Avid.
Finally, Campagnolo produces mechanical rim brakes for road cyclists – and that's it. However, rumours of a Campy-made hydraulic disc brake have been floating for a while, and in 2016 we finally got to see them for ourselves. Watch this space for the full BikeRadar review.
Road bike derailleurs explained
The derailleurs are the mechanisms — mechs for short — that move the chain from one gear to the next. The front mech does the job for the front chainrings, while the rear mech does it for the cassette; both are controlled by the shifters.
Road bike cassettes explained
The cassette is the cluster of sprockets that’s mounted on the rear wheel, and the more sprockets on a cassette, the more ‘speeds’ the groupset is said to have. So if there are nine sprockets, you have a nine-speed groupset; 10 sprockets is a 10-speed groupset and so on.
(Note: ‘speeds’ only refers to the number of sprockets, not the total number of gears available; for that you’d need to factor in the number of chainrings on the crankset.)
Having more sprockets not only provides you with a wider range of gears, but also means the gaps between them tends to be smaller. Smaller gaps mean it’s easier to maintain your pedalling cadence as you shift from one gear to the next, and are therefore preferred by the professionals.
For road bikes, the range of teeth available on cassettes tend to be 11-25 or 11-28, though Shimano, SRAM and Campagnolo are now all offering cassettes with bigger sprockets.
Road bike chains explained
The groupset brand and number of gears dictate the type of chain you require (groupset's with a 'higher' number of gears require narrower chains).
More expensive chains also often have smoother, more durable and corrosion resistant coatings than their cheaper counterparts.
Additionally, some more expensive chains have the pins and plates drilled to remove weight. Note that a chain is a wear item and should be replaced at regular intervals.
Road bike bottom brackets explained
The bottom bracket contains the bearings on which the crankset spins. They come in many shapes and sizes, but as far as road groupsets are concerned, they all fall into one of two categories: press fit and threaded.
Threaded bottom brackets screw into your frame on threads. Press fit bottom brackets, as the name suggests, are pressed into sockets on either side of the frame. Generally speaking, press-fit bottom brackets are more of a faff than threaded ones when it comes to maintenance and compatibility, even if they are supposed to allow manufacturers to make stiffer frames for more pedalling efficiency.
What do I get with a more expensive road groupset?
So does paying more always bring you improved performance? Maybe, but the higher up the range you go, the smaller those performance benefits become, and the increments become less noticeable, while the kit gets more expensive.
Second-tier groupsets (Shimano Ultegra, Campagnolo Chorus, SRAM Force) are almost as good in functional terms as the pro-level components, but they weigh a little more, but the prices aren't so steep.
It was once famously said of bicycle parts: "Strong. Light. Cheap. Pick two." A lighter bike will always accelerate and climb better than a heavier one – but without giving up strength, something has to give.
Whether you're looking at groupsets, wheels or even complete bikes, reduced weight is often the major contributor to increased cost.
With all the road groupsets, the more you spend, the lighter they get. Often the performance of the groupset plateaus at the second tier, with weight being reduced for the extra expense. For example, the difference between Shimano's top two tiers, Ultegra and Dura-Ace, is 258g, while the difference between SRAM's top-range RED and second-tier Force is closer to 400g.
These weight differences are the result of more expensive materials and refined, or more time-consuming, manufacturing processes. In addition to further machining, hole-drilling and high precision, more expensive components often use materials such as carbon fibre, titanium, lightweight aluminium and ceramic bearings to achieve the pinnacle in low weight.
If you're spending more money on a groupset, you'd expect it to outlast a cheaper option. Durability does improve with price, but our experience is that durability also plateaus at the second-tier options, and in some ways, actually starts to decline at the most expensive option.
The more expensive technical components are built with greater precision, refinement and materials that lend themselves to greater longevity. This is apparent in derailleurs and shifters where the cheaper options will develop play and slop overtime, while the better parts often remain like new.
Wear items, such as cassettes and chainrings, however, are often the reverse of this. Cheaper options are made of heavier, but more durable steels, while the more expensive versions are made with lighter, but softer aluminium and titanium metals.
In addition to the benefits of reduced weight, more expensive groupsets find other ways of increasing performance. Most noticeably, higher priced options provide a smoother, more precise and quicker shift between gears. This includes reduced effort at the lever, something that becomes apparent once you've been on the bike for a few hours. It's an area where electronic gears set the benchmark; ultimate precision and speed at the simple push of a button.
Another performance example is increased crankset stiffness to provide crisper shifting and more efficient power transfer from the pedals to the rear wheel. This is achieved with more complex designs and materials that increase strength and stiffness, but don't add weight.
Braking raises an entire new list of benefits as prices goes up. Simply put, the more expensive brakes are stronger, offer better feel and control and stop you with less hand force required.
Besides offering extra gears, it's common for the more expensive groupsets to offer additional features, however subtle they may be. An example of this is the screw-adjustable brake lever position on Shimano's 105, Ultegra and Dura-Ace shifters for improved ergonomics, something that's otherwise done with stick-in rubber pad spacers on cheaper models.
Similarly, Shimano and Campagnolo now offer its higher-end cranksets in a universal size that's cross-compatible with compact, semi-compact or standard sized chainrings. This means that if you ever wish to change your chainring sizes, you can do so without needing an entire new crankset.
Component compatibility issues
It's worth being aware that not all groupset components are interchangeable: for example, you can't run 10-speed Shimano Tiagra shifters with 11-speed Shimano 105 derailleurs.
Different groupsets have different throw (i.e. length of travel) at the brake lever too, so you might not be able to upgrade through one manufacturer’s family as individual parts wear out or break. That said, Shimano groupsets are generally designed to work with each other, providing they share the same number of gears.
For specific compatibility queries, we'd suggest you ask your local retailer before buying.