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 main brands: Shimano, SRAM and Campagnolo.
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 in their hierarchies, then go into greater detail on the individual components and how they differ between brands. We’ll finish by explaining the benefits of the more expensive groupsets and discussing compatibility.
If knobbly tyres are more your thing, we’ve got a separate guide to mountain bike groupsets. And while we’ve covered gravel briefly here, we’ve also got a guide to gravel bike groupsets for all the details on gearing choices.
Jump to:
Need more buying advice?
Does this feel like running before you can walk? We’ve got a separate guide to bike gears, including the different types of bicycle transmissions.
If you’re just looking for some straightforward bike buying advice, start with our beginner-friendly guide to the best bikes to find the most suitable type of ride for your needs.
If you’re sure you want a road bike, but need some general advice on what to look out for, head over to our best road bikes buyer’s guide.
Once you have a better idea of what you’re looking for, we’ve got specific guides for:
By frame material
By price
- Best road bikes under £750
- Best road bikes under £1,000
- Best road bikes under £2,000
- Best road bikes under £3,000
By riding type
Happy to talk groupsets? Keep reading.
What is a groupset?
A groupset comprises all the mechanical parts for your bike – so basically everything except the frame, fork, wheels, handlebar, seatpost and saddle.
You can buy a complete groupset or the individual components and there’s some possibility to mix and match between groupsets, although many items are not inter-compatible.
When you buy a new bike, a bike brand will often sub in some cheaper parts with a groupset, so you might for example get a crankset that’s from a different level or even a different brand from the rest of the groupset.
The components of a full groupset are:
- Crankset (also called the chainset)
- Bottom bracket (the bearings in the frame on which the crankset spins)
- Brake levers/shift levers, usually combined
- Rear derailleur
- Front derailleur
- Cassette (the gear sprockets at the rear of the bike)
- Chain
- Brakes
There’s an explainer of each component and more groupset specifics later in this article.
Shimano groupsets: different levels explained
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 at least half of the global bike components industry.
Shimano road groupset ranking
- Claris R2000: 8-speed
- Sora R3000: 9-speed
- Tiagra 4700: 10-speed
- 105 R7000: 11-speed
- Ultegra Di2 R8100: 12-speed electronic only
- Dura-Ace Di2 R9200: 12-speed electronic only
Shimano gravel groupset ranking
- GRX RX400: 10-speed
- GRX RX600: 11-speed (apart from 10-speed version of crank)
- GRX RX810: 11-speed
- GRX RX815: 11-speed electronic
Entry-level Shimano groupsets: Claris, Sora and Tiagra
!["Claris]("https://images.immediate.co.uk/production/volatile/sites/21/2019/03/claris-1520601513622-jdhhkljjrydb-8b0dae4.jpg?quality=90&resize=620%2C349" "\"Claris")
Shimano Claris R2000
- Gearing: 8-speed
- Shifting: Mechanical
- Braking: Rim
The Shimano component range starts with the budget-priced Shimano 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 (two or three gears at the front). Rim brakes provide the stopping power.
!["Shimano]("https://images.immediate.co.uk/production/volatile/sites/21/2019/03/shimano-sora-1485517666821-1naxpb1pq1ld1-d891100.jpg?quality=90&resize=620%2C349" "\"Shimano")
Shimano Sora R3000
- Gearing: 9-speed
- Shifting: Mechanical
- Braking: Rim, mechanical disc
Next is Shimano 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.
Like Claris, Sora is available with rim brakes only.
!["Shimano]("https://images.immediate.co.uk/production/volatile/sites/21/2020/03/Boardman-SLR8.9c-02-bd63b9d-e1600937941297.jpg?quality=90&resize=620%2C413" "\"Boardman")
Shimano Tiagra 4700
- Gearing: 10-speed
- Shifting: Mechanical
- Braking: Rim, hydraulic disc
Then comes Shimano Tiagra, a 10-speed groupset that offers much of the performance of Shimano 105 (the next step on the ladder), but economises in specific areas, for example with one-piece brake pads rather than higher quality cartridge pads.
Since 2019, Tiagra has included its own hydraulic disc brakes with levers that resemble those of 105. These replaced the lumpy non-series RS405 option. There’s a rim brake option, too.
The latest Shimano Tiagra 4700 groupset deals
Performance Shimano groupsets: 105 and Ultegra
!["Shimano]("https://images.immediate.co.uk/production/volatile/sites/21/2020/06/20200622_SB_5DSR_MG_1782-548c13c-scaled.jpg?quality=90&resize=619%2C413" "\"Shimano")
Shimano 105 R7000
- Gearing: 11-speed
- Shifting: Mechanical
- Braking: Rim, hydraulic disc
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 offer the best combination of performance, durability and value.
The launch of the latest 105 R7000 groupset brought matching hydraulic levers and disc brakes. Previously, the ungainly RS505 levers were considered 105-equivalent.
Shimano 105 remains mechanical only – will Shimano ever bring electronic shifting down to its third-tier road groupset? – and is also offered with rim brakes.
The latest Shimano 105 R7000 groupset deals
!["Mason]("https://images.immediate.co.uk/production/volatile/sites/21/2021/08/Mason-Aspect-with-Ultegra-Di2-4-a5daac0.jpg?quality=90&resize=620%2C413" "\"Mason")
Shimano Ultegra R8100
- Gearing: 12-speed
- Shifting: Electronic
- Braking: Rim, hydraulic disc
Shimano Ultegra sits one level below the professional-level Dura-Ace.
Both groupsets were totally revamped in 2021, becoming 12-speed and moving to semi-wireless shifting on the disc brake groupset, where the shifters communicate wirelessly with derailleurs that are wired to a central battery.
The new Shimano Ultegra R8100 groupset shares essentially all of the same design features as the range-topping Dura-Ace, which we’ll come on to. It even includes a power meter option now.
As a result, it offers all the performance most riders will ever need, with the only difference to Dura-Ace being a slight weight increase in exchange for a considerable price decrease.
Shimano has ditched Ultegra R8100’s mechanical shifting groupset options and only superficially updated the rim brake electronic option (it is still fully wired), so the Di2 Disc version is the only version of the groupset to contain all the latest developments.
The latest Shimano Ultegra R8100 groupset deals
Pro-level Shimano groupsets: Dura-Ace
!["Shimano]("https://images.immediate.co.uk/production/volatile/sites/21/2021/08/Pinarello-Dogma-F-with-Dura-Ace-R9200-5-963aa4f.jpg?quality=90&resize=619%2C413" "\"Pinarello")
Shimano Dura-Ace R9200
- Gearing: 12-speed
- Shifting: Electronic
- Braking: Rim, hydraulic disc
Shimano Dura-Ace is the pinnacle of Shimano’s range and features on many pro-level WorldTour bikes. It combines top-end design with lightweight materials, such as high-grade alloys, carbon fibre and titanium.
Overhauled in 2021 at the same time as Ultegra and with similar improvements, the new Shimano Dura-Ace R9200 now offers 12-speed gearing and semi-wireless shifting that claims to be faster than the previous generation Dura-Ace R9170 Di2 groupset.
The Ultegra and Dura-Ace disc brakes systems have been similarly tweaked. They now use Shimano’s Servo Wave lever ratio for improved modulation, while the calipers offer ten per cent more clearance, making them easier to get running silently, according to Shimano.
Just as in Ultegra R8100, Shimano has killed off the mechanical shifting option for Dura-Ace R9200 and has only made modest changes to the rim brake version of the groupset, meaning the only guise in which all the latest developments are included is the Di2 Disc option.
Dura-Ace is more expensive but lighter than Ultegra, and it also offers a bigger 54-40t chainset option to better cater to the faster speeds of pro riders. Aside from that, the two groupsets are functionally the same.
The latest Shimano Dura-Ace R9200 groupset deals
Shimano GRX gravel components
!["Shimano]("https://images.immediate.co.uk/production/volatile/sites/21/2019/05/shimano-grx-drivetrain-1f0d0b3.jpg?quality=90&resize=619%2C413" "\"Shimano")
In May 2019, Shimano announced a range of components under the name GRX aimed at gravel riding, adventure and bikepacking.
Shimano GRX offers lower gears better suited to these riding disciplines and, in a first for Shimano, ready-made 1× gearing options (i.e. with a single chainring at the front).
GRX isn’t a groupset per se, it’s a range of components that complements Shimano’s existing groupsets, with components at Tiagra, 105, Ultegra and Ultegra Di2 levels. The naming scheme looks like this:
- Tiagra level: RX400
- 105 level: RX600
- Ultegra level: RX800 (Ultegra mechanical shifters are ST-RX810; Ultegra Di2 shifters are ST-RX815)
GRX includes dedicated hydraulic levers, cyclocross-style inline levers, clutch-equipped Shadow RD+ rear derailleurs, front derailleurs and 1× and 2× cranks.
The latest Shimano GRX groupset deals
SRAM groupsets: different levels explained
SRAM came to the fore during the mountain biking boom of the late eighties and established itself off the back of its lightweight GripShift shifters.
SRAM introduced its lightweight Red road groupset in 2007 and now produces an extensive range of components for road and cyclocross bikes, alongside its mountain bike groupsets.
SRAM’s road groupset range comprises four main groups: Apex, Rival, Force and Red (low to high, in terms of price). All of its road groupsets now include a hydraulic disc brake option.
Its three top-tier groupsets – Rival, Force and Red – are also available in 12-speed wireless electronic variants, with the addition of gravel-specific gearing.
With the focus on electronic groupsets, SRAM hasn’t made major updates to its mechanical groupset range for some years now.
SRAM groupset ranking
- Apex: 10-speed
- Apex 1: 11-speed
- Rival: 11-speed
- Rival eTap AXS: 12-speed wireless electronic
- Force: 11-speed
- Force eTap AXS: 12-speed wireless electronic
- Red: 11-speed
- Red eTap: 11-speed
- Red eTap AXS: 12-speed wireless electronic
SRAM XPLR gravel groupset ranking
- Rival eTap AXS XPLR: 12-speed wireless electronic
- Force eTap AXS XPLR: 12-speed wireless electronic
- Red eTap AXS XPLR: 12-speed wireless electronic
Entry-level SRAM groupsets: Apex
!["SRAM]("https://images.immediate.co.uk/production/volatile/sites/21/2019/03/sram-apex-1485517666832-yzqovimdk4kn-76aa011.jpg?quality=90&resize=620%2C349" "\"SRAM")
SRAM Apex
- Gearing: 10-speed
- Shifting: Mechanical
- Braking: Rim, hydraulic disc
SRAM Apex is a 10-speed group that features SRAM’s WiFli system. WiFli offers a wide gear range – between 11 and 32 teeth – for the rear cassette (certain SRAM road derailleurs will go as high as a 36t big cog).
That allows SRAM to offer the wide range of gears usually found by using a triple front chainset setup, without the extra weight and complexity of an additional chainring. Once a unique selling point for SRAM, other manufacturers are now offering similar setups.
SRAM also offers its Apex group in 1×11 gearing, calling it Apex 1. That is to say, just one chainring at the front and 11 gears at the rear.
An Apex 1 rear derailleur can accommodate a cassette with a large 42-tooth cog. Apex 1 also offers hydraulic disc brakes.
The latest SRAM Apex groupsets deals
Performance SRAM groupsets: Rival, Rival eTap AXS, Force and Force eTap AXS
!["SRAM]("https://images.immediate.co.uk/production/volatile/sites/21/2020/05/SRAM-Rival-groupset-9eaa808.jpg?quality=90&resize=620%2C413" "\"SRAM")
SRAM Rival
- Gearing: 11-speed
- Shifting: Mechanical
- Braking: Rim, hydraulic disc
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 with mechanical shifting is 11-speed and can be found with either two chainrings at the front (2×11) or just one (1×11) in the Rival 1 configuration.
The latest SRAM Rival groupset deals
!["SRAM]("https://images.immediate.co.uk/production/volatile/sites/21/2021/04/SRAM-Rival-eTap-AXS-32-8a6e085.jpg?quality=90&resize=619%2C413" "\"SRAM")
SRAM Rival eTap AXS
- Gearing: 12-speed
- Shifting: Electronic
- Braking: Hydraulic disc
In 2021, SRAM launched Rival eTap AXS.
It adds a third tier to SRAM’s wireless electronic 12-speed groupset line-up and uses much of the same tech as SRAM’s pricier options, offering app-based configuration via a smartphone and a power meter.
It’s the cheapest option if you want to go electronic, significantly undercutting Shimano Ultegra Di2. Will Shimano respond by launching an electronic version of Shimano 105?
The latest SRAM Rival eTap AXS groupset deals
!["SRAM]("https://images.immediate.co.uk/production/volatile/sites/21/2020/05/SRAM-Force-1x-groupset-3aaec43.jpg?quality=90&resize=619%2C413" "\"SRAM")
SRAM Force
- Gearing: 11-speed
- Shifting: Mechanical
- Braking: Rim, hydraulic disc
Going up in spec one level, SRAM’s Force group uses lightweight materials such as high-grade alloys and carbon fibre to offer a lightweight mechanical setup.
Like Rival, it’s an 11-speed groupset that can be configured with two chainrings at the front for more gearing range or one chainring (SRAM Force 1) at the front for simplicity.
Latest deals
!["Vitus]("https://images.immediate.co.uk/production/volatile/sites/21/2020/08/Vitus-Energie-EVOS-CRS-cyclocross-bike-review-3-edc09c4-scaled.jpg?quality=90&resize=619%2C413" "\"Vitus")
SRAM Force eTap AXS
- Gearing: 12-speed
- Shifting: Electronic
- Braking: Hydraulic disc
In 2019, SRAM added Force eTap AXS to its range, a 12-speed wireless groupset that competes directly with Shimano Ultegra Di2 and offers a power meter option.
Force eTap AXS was initially launched as a pure road groupset but, in 2020, SRAM added lower and wider-range gearing options to cater to gravel and adventure riders.
These compete directly with Shimano’s GRX range, though as we’ll come on to, SRAM now also has its XPLR gravel gearing.
The latest SRAM Force eTap AXS groupset deals
Pro-level SRAM groupsets: Red and Red eTap AXS
!["While]("https://images.immediate.co.uk/production/volatile/sites/21/2019/03/1416602343085-1ncjkikhpbiwk-a5ab568-e1600943354191.jpg?quality=90&resize=620%2C413" "\"SRAM")
SRAM Red
- Gearing: 11-speed
- Shifting: Mechanical
- Braking: Rim, hydraulic disc
SRAM Red is a pro-level 11-speed groupset and was originally launched as a direct competitor to Shimano Dura-Ace and Campagnolo Super Record.
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 almost certainly the lightest on the market at a claimed 1,747g. Note that it’s difficult to make precise weight comparisons between groupsets because there’s no standard for how to weigh one.
SRAM’s efforts have been focused on its wireless eTap AXS groupsets in recent years, so while mechanical Red is still in existence, it’s fairly long in the tooth and only likely to be seen on used bikes.
!["2021]("https://images.immediate.co.uk/production/volatile/sites/21/2020/09/20200915_SB_5DSR_MG_3059-d71bce0.jpg?quality=90&resize=620%2C413" "\"2021")
SRAM Red eTap AXS
- Gearing: 12-speed
- Shifting: Electronic
- Braking: Rim, hydraulic disc
SRAM Red eTap launched in 2015, as a wireless electronic version of the 11-speed Red groupset. That original launch has been superseded by the 12-speed Red eTap AXS.
Red eTap AXS is available in disc (HRD) and rim brake options.
As with Force eTap AXS, Red eTap AXS now offers wider gear range options, handling cassettes up to 10-36t, plus a Red XPLR drivetrain for gravel riding.
There’s also a Red power meter.
The latest SRAM Red eTap AXS groupset deals
SRAM XPLR gravel components: Red, Force, Rival, RockShox and Zipp
!["Rå]("https://images.immediate.co.uk/production/volatile/sites/21/2021/08/SRAM-RockShox-XPLR-18-230dbd4.jpg?quality=90&resize=620%2C413" "\"Rå")
In August 2021, SRAM announced its new XPLR components, aimed specifically at gravel riding and to fill the gap between its road-specific and mountain bike groupsets.
SRAM XPLR spans Rival, Force and the top-tier Red groupsets and comes with wireless electronic shifting at all levels.
SRAM has chosen 12-speed gearing in a dedicated 1× layout for XPLR with cassettes that have a 10-44-tooth range. There is a new eTap AXS rear derailleur design to accommodate this gearing for each level.
One of the most noticeable things about XPLR as a whole package is that it includes components from RockShox and Zipp – two brands also owned by SRAM – including a new gravel-specific suspension fork, a dropper post that provides a small amount of suspension, and gravel wheels.
Latest deals
Campagnolo groupsets: different levels explained
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, bike collectors and those who think an Italian bike must have an Italian groupset.
Campagnolo groupset ranking
- Centaur: 11-speed
- Chorus: 12-speed
- Record: 12-speed
- Record EPS: 12-speed electronic
- Super Record: 12-speed
- Super Record EPS: 12-speed electronic
Campagnolo gravel groupset ranking
- Ekar: 13-speed
Entry-level Campagnolo groupsets: Centaur
!["Campagnolo]("https://images.immediate.co.uk/production/volatile/sites/21/2019/06/Campagnolo-Centaur-groupset-3bcc1e7.jpg?quality=90&resize=620%2C413" "\"Campagnolo")
Campagnolo Centaur
- Gearing: 11-speed
- Shifting: Mechanical
- Braking: Rim
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 £1,000 / $1,200 / AU$1,900.
The entry-level Campagnolo Centaur groupset sits around the same area as Shimano 105 or SRAM Rival. It’s 11-speed, with mechanical shifting, and only available with rim brakes.
Latest deals
Performance Campagnolo groupsets: Chorus
!["Condor]("https://images.immediate.co.uk/production/volatile/sites/21/2020/10/20200915_SB_5DSR_MG_2936-539bb6f.jpg?quality=90&resize=620%2C413" "\"Condor")
Campagnolo Chorus
- Gearing: 12-speed
- Shifting: Mechanical
- Braking: Rim, hydraulic disc
Sitting just below the Record family is the 12-speed Campagnolo 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.
Chorus offers a hydraulic disc brake option and handles cassettes with up to 11-34 teeth.
The latest Campagnolo Chorus groupset deals
Pro-level Campagnolo groupsets: Record and Super Record
!["Campagnolo]("https://images.immediate.co.uk/production/volatile/sites/21/2019/03/campagnolo_record_disc-1542722687430-1v3fxl49ubw7i-8c82f68-e1574783288826.jpg?quality=90&resize=620%2C413" "\"Campagnolo")
Campagnolo Record
- Gearing: 12-speed
- Shifting: Mechanical
- Braking: Rim, hydraulic disc
Campagnolo Record is a premium mechanical groupset from the Italian brand, with 12-speed shifting, and rim and hydraulic disc braking options.
The latest Campagnolo Record groupset deals
!["Road]("https://images.immediate.co.uk/production/volatile/sites/21/2019/07/Colnago-V3Rs-first-ride-cfb8449.jpg?quality=90&resize=620%2C413" "\"Colnago")
Campagnolo Super Record
- Gearing: 12-speed
- Shifting: Mechanical
- Braking: Rim, hydraulic disc
Campagnolo also offers an even higher-level groupset in the form of Super Record. While very similar to Record, it uses even fancier materials to lighten and enhance each and every part.
The latest Campagnolo Super Record groupset deals
Campagnolo Super Record EPS
- Gearing: 12-speed
- Shifting: Electronic
- Braking: Rim, hydraulic disc
At one time there were Chorus, Record and Super Record EPS electronic groupsets, but now the only current EPS offering is 12-speed Super Record EPS (and its disc counterpart).
This is the best of the best as far as Campagnolo is concerned and is usually only found on the most expensive pro-level road machines.
The latest Campagnolo Super Record EPS groupset deals
Campagnolo gravel groupsets: Ekar
!["Full]("https://images.immediate.co.uk/production/volatile/sites/21/2020/09/ekar-groupset-all-components-27031fe.jpg?quality=90&resize=620%2C413" "\"Full")
Campagnolo Ekar is the brand’s 1×-specific 13-speed groupset, with mechanical shifting, which is designed explicitly with gravel and adventure riding in mind.
With cassettes that start with a diminutive 9-tooth cog, Ekar matches the range of 2× drivetrains “without compromise”, according to Campagnolo.
Campagnolo also claims Ekar is the lightest gravel-specific groupset out there, weighing in at a claimed 2,385g for the complete package.
Latest deals
Road bike groupset components
Now 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.
Road bike crankset/chainset explained
!["Shimano]("https://images.immediate.co.uk/production/volatile/sites/21/2020/06/20200622_SB_5DSR_MG_1781-acf1af9-scaled.jpg?quality=90&resize=619%2C413" "\"Shimano")
Single, double and triple chainrings
The crankset (or chainset) is the largest part of any groupset and comprises the chainrings, 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 chainrings used: double (the most common on the road, often referred to as 2x or 1x/’one-by’); single (popular in mountain biking and cyclocross/gravel, and often referred to as 1x or ‘one-by’); and triple (an older standard that’s rarely seen on new bikes).
Double crankset variations
- The standard double crankset is most commonly used by pro riders and historically consists of a 53t big ring and 39t small ring, or 53/39
- The semi-compact crankset – or pro-compact – is 52/36. This gives you a slightly easier climbing gear while still retaining a big top gear. It is a popular option among competitive amateur riders
- The compact crankset is 50/34. It has become very popular thanks to its combination of easy gearing and low weight
- Super-compact or sub-compact cranksets offer an even lower gear range on double chainrings, such as 48t/32, 48/31 or 46/30. These are becoming popular with gravel riders and bikepackers who want the low, closely spaced gearing a 2x setup can offer.
- SRAM upset the applecart when it went 12-speed and introduced cassettes with a 10t small cog, rather than 11 teeth. That lets it achieve similar gear ratios with smaller chainrings, saving weight and offering even wider ranges. SRAM’s second-tier Force eTap AXS groupset now includes a low-range 43/30t option, for example.
Triple cranksets
- The triple is an older type of chainset commonly seen on vintage road bikes and touring bikes. It offers a wide range of gears, but at a weight penalty by adding a third chainring. It typically 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 ‘spinny’ ring when loaded down with panniers.
Single cranksets
- The single-ring crankset has only one chainring. To compensate for the loss of the smaller, inner ring, a 1× crankset is often matched to a wider-range cassette. Single ring cranksets use alternating wide and narrow teeth with a higher profile, to aid chain retention.
Road bike shifters explained
!["GRX]("https://images.immediate.co.uk/production/volatile/sites/21/2020/02/Enigma-Escape-titanium-9-367b116-scaled.jpg?quality=90&resize=619%2C413" "\"GRX")
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 mechanical gears on a Shimano-equipped bike is slightly different to how you shift on a Campagnolo- or SRAM-equipped bike.
Electronic shifting 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.
For a full explanation of how the different systems change gear, read our detailed article on how to change gear on a road bike.
Road bike brakes explained
!["Rim]("https://images.immediate.co.uk/production/volatile/sites/21/2019/06/Brake-types-47a0265.jpg?quality=90&resize=620%2C413" "\"Rim")
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, caliper rim brakes were the only type used on most road bikes, but recent years have seen road bike braking options expand to take in direct-mount rim calipers, hydraulic rim calipers (these remain exceptionally rare), cable-operated disc brakes and hydraulic disc brakes.
!["Disc]("https://images.immediate.co.uk/production/volatile/sites/21/2020/04/MG_4706-f31d390-scaled.jpg?quality=90&resize=619%2C413" "\"Disc")
Hydraulic disc brakes are generally considered to be the best all-round option, but which type of brake is best for you is dependent on a number of factors. Understanding how road disc brakes work will help you decide.
All three groupset brands now offer hydraulic disc brake options alongside rim brakes for the majority of their groupsets, and they’re now dominant on new bikes.
Road bike derailleurs explained
!["Shimano]("https://images.immediate.co.uk/production/volatile/sites/21/2020/02/Shimano-105-R7000-groupset-review-3-of-9-37711f4.jpg?quality=90&resize=620%2C413" "\"Shimano")
The derailleurs are the mechanisms – sometimes mech for short – that move the chain from one gear to the next.
The front derailleur does the job for the front chainrings, while the rear derailleur does it for the cassette; both are controlled by the shifters.
Road bike cassettes explained
!["Force]("https://images.immediate.co.uk/production/volatile/sites/21/2019/12/Force-AXS-vs-Ultegra-Di2-H2H-24-d1b44ea.jpg?quality=90&resize=620%2C413" "\"Force")
The cassette is the cluster of sprockets mounted on the rear wheel. The more sprockets on a cassette, the more ‘speeds’ the groupset is said to have.
So, if there are 10 sprockets, you have a 10-speed groupset; 11 sprockets is an 11-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 jumps between them tend to be smaller.
Smaller gaps mean it’s easier to maintain an optimal pedalling cadence as you shift from one gear to the next, and are therefore preferred by racers.
For road bikes with a double crankset, 11-28t is probably the most common cassette range, but Shimano, SRAM and Campagnolo all offer a huge range of choices to suit your riding.
It’s also becoming more common to see wider range cassettes fitted as standard, with ratios such as 11-32t or even 11-34t appearing on some bikes, while SRAM offers a 10-36t 12-speed cassette in its eTap AXS Force and Rival ranges.
Road bike chains explained
!["Flat-topped]("https://images.immediate.co.uk/production/volatile/sites/21/2019/12/Force-AXS-vs-Ultegra-Di2-H2H-29-e584f7a.jpg?quality=90&resize=620%2C413" "\"Flat-topped")
The groupset brand and number of gears dictate the type of chain you require (groupsets with a ‘higher’ number of gears require narrower chains).
More expensive chains also often have smoother, more durable and more 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. There are tools that will tell you when to replace your bike’s chain.
Failure to do this will accelerate wear on your cassette and chainrings, but you can extend chain life by cleaning it regularly and only using the best chain lubes for your bike.
Road bike bottom brackets explained
!["Bottom]("https://images.immediate.co.uk/production/volatile/sites/21/2019/03/shimano-ultegra-threaded-bottom-bracket-1485528756285-ri1uauzlwz0j-112b12d.jpg?quality=90&resize=620%2C349" "\"Bottom")
The bottom bracket contains the bearings on which the crankset spins and it fits into your frame.
Bottom brackets come in many shapes and sizes – we’ve got a complete guide to bottom bracket standards – but as far as road groupsets are concerned, they all fall into one of two categories: press-fit or threaded.
Threaded bottom brackets screw into your frame on threads. Press-fit bottom brackets, as the name suggests, are pressed into the frame and held in place by friction.
Generally speaking, press-fit bottom brackets are less convenient than threaded ones when it comes to maintenance and compatibility, but many manufacturers favour them for purported weight and stiffness benefits, as well as ease of manufacturing.
What do I get with a more expensive road groupset?
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 a lot more expensive.
Second-tier groupsets (Shimano Ultegra, Campagnolo Chorus, SRAM Force) are generally as good in functional terms as the pro-level components and considerably cheaper, but they weigh fractionally more and have fewer exotic shiny bits.
Weight
!["Shimano]("https://images.immediate.co.uk/production/volatile/sites/21/2019/06/Shimano-SRAM-bb-7c982fb.jpg?quality=90&resize=620%2C413" "\"Shimano")
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 be compromised.
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. The amount of weight that you save for your money diminishes dramatically at the upper end, though.
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 and performance.
Durability
!["Female]("https://images.immediate.co.uk/production/volatile/sites/21/2020/11/Winter-cycling1-c34ad0a.jpeg?quality=90&resize=619%2C413" "\"Female")
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 over time, 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 sometimes made from lighter but softer aluminium or titanium alloys.
Performance
!["SRAM]("https://images.immediate.co.uk/production/volatile/sites/21/2020/03/Force-eTap-AXS-hero-1-d27612a-scaled.jpg?quality=90&resize=619%2C413" "\"SRAM")
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 in some cases 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 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 go up. Simply put, more expensive brakes are stronger, offer better feel and control, and stop you with less hand force required.
This difference is much more apparent with rim brakes, though. There’s hardly any meaningful performance difference between low- and high-end hydraulic disc brakes.
Additional features
Besides offering extra gears, the more expensive groupsets usually get new features first.
Shimano first launched Di2 electronic shifting at the Dura-Ace level, before trickling it down to Ultegra. The same is true of more mundane details – Dura-Ace was the first to get reach adjustment using a built-in screw rather than ugly shims, a feature now found all the way down to Claris level.
Similarly, Shimano and Campagnolo now offer their 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 a new crankset.
Groupset compatibility issues
!["SRAM]("https://images.immediate.co.uk/production/volatile/sites/21/2020/05/Force-Wide-John-Watson-d1193bf.jpg?quality=90&resize=620%2C413" "\"SRAM")
It’s worth being aware that not all groupset components from a given manufacturer are compatible with one another, even in cases where it seems like they should be.
Manufacturers tend to update their ranges incrementally over time so you can’t always assume, for example, that one 11-speed component will work with another if they’re not from the same year or groupset.
There are differences in the precise amount of cable pulled by different rim brake levers too, so you may not get optimal performance if you move up the hierarchy when you replace individual parts.
That said, groupsets of a given brand are generally designed to work with each other, providing they share the same number of gears. (i.e. Shimano 11-speed with Shimano 11-speed, Campagnolo 11-speed with Campagnolo 11-speed.)
For specific compatibility queries, we’d suggest you ask your local retailer before buying, consult manufacturer technical documents online, or seek advice on our forum. Shimano, for example, maintains very detailed compatibility charts.