What is a road bike groupset? And what should you look for in the key components that make one up?

What is a groupset?

On bikes, the term groupset, or “gruppo”, refers to any mechanical or electronic parts that are involved in braking, changing gear, or the running of the drivetrain. That means the shifters, brake levers, front and rear brake calipers, front and rear derailleurs, crankset, bottom bracket, chain, and cassette.

If you’re buying a bike, then, after the frame, the groupset is the second thing that you should look at, and is a key determining factor in working out whether the bike in front of you offers good value for money or not.

There are three main manufacturers of groupsets and bike components.  Shimano is the largest and best known, while the other two of the “big three” are Campagnolo and SRAM.  All three manufacturers offer a range of groupsets at competing price points.

Read further down the page for information on individual components – whilst you’ll find information about the ‘big three’ providers below…


Shimano groupsets

The high majority of built road bikes come with a primarily Shimano groupset, though you’ll sometimes find they include some components from other brands to keep costs down – such as TRP brakes or FSA chainsets.

The Japanese brand offers a wide range of groupsets – starting with Claris and Sora, which you’ll find on entry level road bikes. Tiagra is the next step up, followed by Shimano 105 which is typically specced on bikes costing upwards of £1000.

Shimano 105 is considered Shimano’s first performance groupset, and for many people it is the best option in combining, performance, value and longevity. Ultegra is next and is very similar to Dura-Ace in terms of performance, though Dura-Ace is lighter – you’ll find Ultegra on bikes from around £1500.

Shimano currently produces Ultegra and Dura-Ace in electronic versions, denoted by Di2, and newer Dura-Ace, Ultegra and 105 models now come with disc brakes.

Shimano groupset hierarchy

Links in the ‘buy now’ column will take you to retailer’s sites. If you click on this then we may receive a small amount of money from the retailer if you purchase the item,  this doesn’t affect the amount you pay.

Name What is it? Weight* RRP** Buy now (from)
Shimano Dura Ace R9170 Di2, disc, 11 speed 2389g £3214.82 £2,149.99
Shimano Dura Ace R9150 Di2, rim, 11 speed 2051g £2944.84 £1,999.99
Shimano Dura Ace R9120 Mechanical, disc, 11 speed 2355g (/2445g w cables) £2104.91 £1384.99
Shimano Dura Ace R9100 Mechanical, rim, 11 speed 2007g (/2097g w cables) £1834.92 £999.99
Shimamo Ultegra R8070 Di2, disc, 11 speed 2627g £1979.83 £1169.89
Shimano Ultegra R8050 Di2, rim, 11 speed 2353g £1669.83 £995.49
Shimano Ultegra R8020 Mechanical, disc, 11 speed 2512g £1244.92 £729.99
Shimano Ultegra R8000 Mechanical, rim, 11 speed 2266g £954.92 £562.99
Shimano 105 R5800 Mechanical, rim (outgoing), 11 speed 2810g Outgoing £349.99
Shimano 105 R7025 Mechanical, disc, 11 speed TBC £816.91 Not yet available
Shimano 105 R7000 Mechanical, rim, 11 speed TBC £566.92 Not yet available
Shimano Tiagra 4700 Mechanical, rim, 10 speed 2585g £511.92 £229.99
Shimano Sora R3000 Mechanical, rim, 9 speed Unconfirmed £456.92 Components
Shimano Claris R2000 Mechanical, rim, 8 speed Unconfirmed £396.92 Components

* Weights will always be estimates, as they’ll vary depending upon chainring size, crank length, cassettes used and some official weights do not include components such as cables and mineral oil/hoses for disc brakes.

** RRPs are based upon Shimano’s official retail price of components added together. Retailers create their own RRPs, based upon the cost of individual components, so listed prices will vary.

Shimano Dura Ace – R9100 series

The newest version of Shimano’s top end groupset is the Dura Ace R9100 series.

Shimano works on four year product cycles, and the R9100 series comes with a reinvented aesthetic which features sharper edges and an asymmetic crank arm that is designed to lower the weight and offer better shifting.

>>> Read more: Shimano Dura Ace R9100 vs Ultegra R8000

Shimano groupset dura ace 9100

The rear mech can now cater for cassettes up to 30T, and we even went to 32T (though this isn’t covered under warranty as it’s not officially recommended).

The mech in question now takes notes from the MTB specific XTR version, with a lower profile that is better protected. The front dérailleur has been reinvented, with a more compact offering that can allow for better tyre clearance.

It’s worth noting that the spacing on the R9100 chainrings has been adjusted – so combining new components with old Dura-Ace mechs is not advised.

The Di2 version (R9150) offers ‘synchronised shifting’ which puts an end to cross-chaining as it controls both levers, though you can turn it off in the settings if you don’t want the groupset to take over.

Disc brake models (R9120, mechanical disc and R9170, di2 disc) have Dura-Ace hydraulics, which use ‘Freeza brake calipers’ to cut down on heat build up.

Upgrades from Shimano Ultegra include lighter shifters, greater heat dissipation on disc brake rotors, and a carbon rear dérailleur cage.

Shimano now offers its own Dura Ace power meter, too.

Shimano Ultegra – R8000 series

Shimano Ultegra is consistently considered to be the thrifty racer’s choice, carrying much of the performance of Dura Ace, with a reduced price tag.

However, a few of the changes made with the newest creation also make Ultegra a better choice for those looking to tackle gravel and mixed terrain.

>>> Read more: Shimano Ultegra R8000 vs 6800

Shimano groupset Ultegra - R8000 series

The newest Shimano Ultegra family – R8000 – mimics the updated aesthetic seen across it’s more expensive sibling, but aside from looks, other changes include the capacity to suit an 11-34 cassette and brake calipers comfortable with 28c tyres.

The hoods have been slimmed down, and now have a grippy pattern (like Dura Ace), and the dérailleurs have received a similar treatment to new Dura Ace, promising smoother gear changes.

The overall weight has actually increased slightly on the outgoing Ultegra 6800, but Shimano promises better shifting and stiffness.

Disc brake iterations – R8020 (mechanical) and R8070 (di2) – use Ice technologies Freeza properties to reduce heat build up and the shifters are slimmer than former models.

Shimano 105 – R7000 series

The entry level performance groupset was the last to get an update, but as you’d expect with trickle down technology, Shimano 105 R7000 has received a couple of the luxuries afforded to newer Ultegra.

>>> Read more: Shimano R7000 vs R5800 in detail 

Shimano groupset 105 - R7000 series

You get the stubby cranks seen in new Dura Ace and Ultegra, and there’s three different crankset options (54-39, 52-36 or 50-34 ) to be paired with 11-30 or 11-34 cassettes.

The inner ring has been repositioned, so cross-chaining becomes less noticeable, and the shifter hood has gone on a diet. There’s now dedicated 105 R7000 hydraulic disc brakes, which are identical to Ultegra’s R8020 versions.

Shimano Tiagra –  4700

Shimano groupset Tiagra 4700

Shimano Tiagra groupsets and below have yet to receive the more recent update, with updated aesthetic and update mechs.

The 2016 update – Shimano Tiagra 4700 – however, did incorporate gear and brake cables that could be fed beneath bar tape, reducing the “anti aero loop” on previous additions. It’s compatible with flat bar bikes, too.

Unlike the others above, which are 11-speed, Tiagra is still 10- speed, and the chainsets available are  52/36t, 50/34t and 50/39/30t – the largest, most race focused 53/39 option available elsewhere won’t be found here.

Shimano Sora – R3000

Shimano groupset Sora - R3000

Shimano showed its Sora groupset (R3000) a bit of love in 2017, with new shifters, brakes and rear derailleurs which carry a more sophisticated aesthetic.

The chainset, like Tiagra, is now four arm which allows it to be lighter – and it comes as a 50-34 compact or 50-29-30 triple and the whole set up can be introduced to flat bar bikes (on a five arm crankset with chainguards). Casssettes can be as large as 11-34, which will allow plenty of gear options. 

The groupset continues to be 9-speed, but it does have new shifters which allow for neater internal cable routing. The rum brakes are said to be improved with 20 per cent greater stopping performance on the outgoing version thanks to the addition dual pivot calipers.

Shimano Claris – R2000

Shimano groupset Claris - R2000

Shimano’s entry level gorupset hasn’t had an overhaul since 2013, but the 8-speed R2000 set up still provides excellent value.

There is a cheaper option – Shimano Tourney – but you won’t find it on many built bikes and Claris has one up on it because it uses the same Dual Control shifting action as the other key groupsets. Tourney, on the other hand, still features a thumb lever on the inside of the hood to shift up. Claris also has its own matching brake system.

Though Claris is perfectly effective, the let down is its 8-speed shifting, which doesn’t provide the rider with a particuarly large selection of gears and means that jumps between cogs can be noticeable.

SRAM groupsets

Illinois-based SRAM is the newest of the three main brands and offers the lightest commercially available groupset in SRAM Red, and the only wireless groupset in SRAM Red eTap.

Apex is SRAM’s entry level and roughly comparable to Tiagra. Next up the ladder is Rival, which was named to rival Shimano 105, and SRAM Force sits above Ultegra and below Dura-Ace.

The three lower models in the SRAM range are also available with just a single ring (1x) at the front, and every model in the range is also available with matching disc brakes.

Across the mechanical range, SRAM uses ‘DoubeTap’ – which means that the gear shifter sits behind the brake lever. On the left, a quick click of the lever takes you into a smaller chaingring, and a longer push moves you into a bigger ring – though obviously this doesn’t apply on the 1x ranges. On the right, a short push takes you into a smaller cog (more resistance) on the cassette, and a long swipe takes you into a bigger cog (less resistance).

SRAM groupset hierarchy

Click on the groupset titles for reviews of the systems that we’ve tested.

Links in the ‘buy now’ column will take you to retailer’s sites. If you click on this then we may receive a small amount of money from the retailer if you purchase the item,  this doesn’t affect the amount you pay.

What is it? Weight*  RRP** Buy it now
SRAM RED eTap HRD Electronic, disc, 11 speed 2361g £2658 £1791.99
SRAM RED eTap Electronic, rim, 11 speed 1750g £2472 £1089
SRAM RED 22 HRD Mechanical, disc, 11 speed 2119g £2044 £1503.50
SRAM RED 22 Mechanical, rim, 11 speed 1741g £1890 £999.94
SRAM Force 1 Mechanical, disc, single chainring 2466g £1204 £890
SRAM Force HRD Mechanical, disc, 11 speed Unconfirmed £1127 £254.99 (single, brake and shifter only)
SRAM Force 22 Mechanical, rim, 11 speed 2097g £975 £689.42
SRAM Rival 1 Mechanical, disc, single chainring 2690g £979 £568
SRAM Rival HRD Mechanical, disc, 11 speed Unconfirmed £939 £194 (single, brake and shifter only)
SRAM Rival 22 Mechanical, rim, 11 speed 2348g £667 £341.98
SRAM Apex 1 Mechanial, disc, single chainring 2719g £828 £522.14
SRAM Apex HRD Mechanical, disc, 10 speed Unconfirmed  Unconfirmed £191.99 (single, brake and shifter only) 
SRAM Apex Mechanical, rim, 10 speed 2419g Unconfirmed £314.94

* Weights will always be estimates, as they’ll vary depending upon chainring size, crank length, cassettes used and some official weights do not include components such as cables and mineral oil/hoses for disc brakes.

** RRPs are based upon Shimano’s official retail price of components added together. Retailers create their own RRPs, based upon the cost of individual components, so listed prices will vary.

SRAM Red

SRAM groupsets eTap Hydro

SRAM Red is available on its own (still boasting incredible performance), with hydraulic disc brakes, with e-Tap and of course with hydraulic disc brakes and eTap.

Being wireless, eTap is impressively light, and won itself a place in our Editor’s Choice awards of 2017. It uses SRAM’s own system ‘AIREA’ instead of ANT+ or Bluetooth.

To shift using eTap, you move into a smaller cog at the rear by pressing the paddle behind the right brake lever. You move into a larger cog by pressing the paddle behind the left lever. The front mech is operated by pressing both levers together.

As denoted by the ’22’, SRAM Red is 11 speed and the American based brand promises that the symptoms of cross-chaining are minimal so you really can use all 22.

SRAM Red groupsets are also on offer with a mid-cage ‘WiFli’ rear deraillieur, which makes the use of a 32-tooth cassette possible (without it your max is 28 tooth), and SRAM Red chainsets can also come available with a Quarq power meter built in.

SRAM Force

SRAM Groupsets SRAM Force

SRAM Force is available as SRAM Force 22 (11 speed), SRAM Force 1 (single chainring) and both options can come with rim, hydraulic rim or hydraulic disc brakes.

Like SRAM Red, Force is 11-speed, and when it grew into its extra gears it also inherited design features from its more costly sibling. Whilst a little heavier than Red, Force is usually considered on par with Shimano Ultegra.

The 1x version can accomodate cassettes up to 11-36, and comes with chainrings from 38 to 54 tooth. A Clutch 2 derailleur helps guard against chain slap – a technology which was previously considered an off-road domain but has become more popular on the road (and gravel) of late.

SRAM Rival

sram groupset sram rival

 

Like SRAM Force, you can get SRAM Rival in 22 configuration, 1x (as pictured above), and with hydraulic disc, hydraulic rim or mechanical rim brakes.

The major difference between this and other options above is that the cranks, levers and rear mechs move from being constructed from carbon fibre, to aluminium.

Also, when it comes to the hydraulic levers, they’ve not received the updates seen elsewhere in the range, so are a bit larger compared to the downsized hoods you’ll see at the likes of SRAM Red HRD.

The 1x groupset comes with an X-Horizon rear derailleur, which includes a clutch mechanism to reduce chainslap.

SRAM Apex

sram groupsets sram apex

The most notable different between SRAM Apex and the rest of the line up is that it’s a 10-speed groupset, which means jumps between gears become a bit more noticeable.

Available chainsets are 53/39, 50/34 and 48/35 – it’s notable that you still get a standard double (53/39) as Shimano fazes this out in its lower end offerings. You can still accomodate an 11-32 cassette thanks to the availability of the WiFLi rear derailleur and there’s 1x in the line up, too.

Campagnolo groupsets

Campagnolo, affectionately referred to as “Campag” or “Campy”, is a company rich in cycling heritage. The Italian brand can boast of equipping the winning bikes of the 2014 Giro d’Italia and Tour de France.

Historically it is famous for inventing the rear derailleur and many other key innovations, such as quick release skewers.

The entry-level groupset, Veloce starts higher than Shimano and sits above Sora and Tiagra. Potenza competes with Ultegra and SRAM Force, with Chorus sitting just below the Record components, while Super Record sits atop the Campagnolo hierarchy.

Campag offers three electronic groupsets, which are denoted by the term EPS (Electronic Power Shift). Super Record EPS is the most expensive commercially available groupset.

In May 2017, Campagnolo announced its new disc brake groupsets – with discs available across Chorus, Record and Super Record groupsets. It teamed up with Magura, the German brake and suspension brand, to develop the cylinder system and claimed the braking was 23-26% faster in the wet when compared with the competition.

Then in April 2018, Campagnolo broke new ground, launching with 12 speed versions of Record and Super Record.

Campagnolo’s shifting system differs from the key competition – with a lever behind the brake on the ‘Ergopower’ shifters which moves the chain one way, and a thumb lever on the inside of the shifter which sends it the other way. The other magic trick is ‘Ultrashift’, which makes it possible to give the lever a longer push to smash through multiple gears on the cassette in one go.

The brand’s systems are well known for their distinctive ‘clunk’ – something Campag says dedicated users value so much hat the electronic system was developed to provide the same degree of feedback.

Campagnolo groupset hierarchy

Links in the ‘buy now’ column will take you to retailer’s sites. If you click on this then we may receive a small amount of money from the retailer if you purchase the item,  this doesn’t affect the amount you pay.

Groupset What is it? Weight* RRP** Buy now (from)
Super Record H11 EPS Electronic, disc, 11 speed Unconfirmed £3937
£2725
Super Record EPS Electronic, rim, 11 speed 2078g £3712 £2725
Super Record H11 Mechanical, disc, 11 speed 2228g £2878.60
Super Record Mechanical, rim, 12 speed 1940g £2603.05 £2615
Record H11 EPS Electronic, disc, 11 speed Unconfirmed £3627
Record EPS Electronic, rim, 11 speed 2178g £3174.55 £2779.99
Reccord H11 Mechanical, disc, 11 speed 2260g £2160.57 £1740.70
Record Mechanical, rim, 12 speed 2039g £1750.06 £1764.99
Chorus EPS Electronic, rim, 11 speed 2308g £2203 £1348.99
Chorus H11 Mechanical, disc, 11 speed 2613g £2047.07 £1654
Chorus Mechanical, disc, 11 speed 2120g £1330.65 £989.49
Potenza Disc Mechanical, disc, 11 speed Unconfirmed £1387.50  £1327.99
Potenza Mechanical, rim, 11 speed 2412g £818.76 £599
Centaur Mechanical, rim, 11 speed Unconfirmed £588.12  £399.95
Veloce Mechanical, disc, 10 speed Unconfirmed Unconfirmed Components

* Weights will always be estimates, as they’ll vary depending upon chainring size, crank length, cassettes used and some official weights do not include components such as cables and mineral oil/hoses for disc brakes.

** RRPs are based upon Shimano’s official retail price of components added together. Retailers create their own RRPs, based upon the cost of individual components, so listed prices will vary.

Campagnolo H11 Disc brake groupsets

Bianchi Infinito CV chorus disc

Campagnolo was a little late to the party with disc brakes, arriving in spring/summer 2017 – but it promises improved performance compared to the competition, with braking that’s 23-26 per cent faster in the wet with less force.

It’s disc brake system is called ‘H11’ – and the shifters, chain set and brake calipers are the across H11 Record, Super Record and Chorus – differences presenting themselves in the chain, cassette and dérailleurs. The lower end Potenza groupset comes with an ‘H10’ disc brake groupset, which features aluminium shifters instead of carbon.

To create the system, Campag teamed up with German brake and suspension manufacturer Magura – who helped develop the cylinder and oil system. The brakeset features an ‘Adjustment Modulation System’ (AMS) which allows users to change the degree of bite, as well as a ‘patented anti-vibration, noise-reduction solution’ in the shape of a bonded layer on the back of each brake pad. The 22mm diameter pistons are made from phenolic resin, which the brand claims offers superior heat insulation and a magnetic spring has replaced a metal approach which is said to add to reaction time and consistency.

There are size specific calipers – you can run 160mm at front and rear and 160mm or 140mm at the rear. They’re designed to fit any flat mount frameset and there’s no need for spacers.

Campagnolo EPS

EPS versions are available at Campagnolo Super Record, Record and Chorus level. The system powers itself via a rechargeable battery which sits in the frame and the 2016 update included development of the Power Unit and Interface Unit, making them slimmer and increasing compatibility with more frames – including aero bikes.

The shifting pattern stays the same, but the front derailleur adjusts itself slightly if you’re chaincrossing, to help facilitate a smoother change. Configuration is set up via the ‘MyCampy’ App which can transmit information wirelessly via Bluetooth (BLE) or ANT+.

Campagnolo Super Record

Campagnolo Super Record EPS

Campagnolo Super Record is available in EPS, EPS H11, mechanical H11 or plain old Super Record mechanical rim brake – and as of this year you can get the mechanical system with 12-speed, too.

The 12-speed system comes with new chainsets, front and rear derailleurs, rim and disc brakes as well as shifters – but it’s compatible with existing wheels and frames. There are two cassette options – 11-29 and 11-32 – the reasoning being that racers don’t need to stick to smaller gear ratios in order to minimise gaps between cogs with the 12-speed system.

Being top of the performance ladder, Super Record is loaded with carbon and titanium, allowing for a low overall weight. The crankset, for example, is carbon, with alloy chainrings and a titanium axle, the derailleurs are predominantly carbon with ceramic bearings used and the body of the shifter is constructed from composite.

Alongside the impressive performance of the H11 brakes, we’ve always found Campagnolo’s direct mount rim brakes – available down to Chorus level – quick to react and effective.

The dérailleurs allow for full use of  the cassette, in either chainring, without chainrub on the front mech, and the chainsets come in 53/39, 52/36 and 50/34 combos whilst cassettes can be anywhere from 11-23 to 11-29.

Campagnolo Record

The performance differences between Super Record and Record aren’t huge – there’s a little bit less carbon, which reflects in a slight weight increase – for example, the crankset weighs 651g as opposed to 603g at Super Record standard.

The shifters still have a composite body, as is the majority of the dérailleurs structure, though the ceramic bearings have disappeared from the rear and been replaced by bushings.

Campagnolo Chorus

Campagnolo Chorus Ergopower H11 groupset

Chrous comes in EPS and with H11 disc brakes, but not with 12-speed as the upper echelons offer.

The rear derailleur uses rubber pulleys as opposed to the ceramic bearings at Super Record level. The crankset has been beefed up to 683g (compared to 603g for Chorus), and there’s similar increases across the group.

Campagnolo Potenza

Potenza is ‘middle ground’ for Campagnolo, but it’s actually comparable to Shimano Ultegra, so it’s certainly not entry level by any stretch of the imagination.

One notable difference is a longer inside lever, when compared with that found on the top end systems – this answers complaints that the thumb tab was hard to reach when in the drops. There’s also a larger rear dérailleur, which can cater for cassettes up to 11-32.

Campagnolo Centaur

The closest comparison to Veloce is Shimano 105 – it comes in black or silver, though the latter is more expensive.

The dropped inner thumb paddle has been continued into this level, and the chainsets available are 50/34 and 52/36 – denoting that Campag doesn’t consider this to be a race level product with a missing 53/39.

Campagnolo Veloce

The entry-level option from Campagnolo, Veloce is also available in silver or black, and it’s still a 10-speed system with a lack of carbon use within the construction.


Components of a road bike groupset

Shifters

campagnolo disc brakes shifters 2

Campagnolo shifters use a thumb shifter on the inside of the hoods to shift up

The shifters on a road bike are used change gear.  Shimano’s STI (Shimano Total Integration) shifters are the most common design.  The brake lever can be pushed inwards (sideways) to change up into an easier gear. To change down, there is a second lever behind the first that can be separately pushed inwards.  To apply the brake, both levers are pulled backwards, towards the rider.

With shifters from Campagnolo and SRAM you brake in the same way but shift slightly differently. With Campag you shift down using a shifter behind the brake lever, and change up using a thumb shifter on the inside of the hoods.

On mechanical SRAM groupsets, you shift up by pushing the lever in one notch, and change down by continuing to push it in slightly further. However with SRAM Red eTap, the American company’s electronic groupset, you shift up at the back by pressing the right shifter, down at the back by pushing the left shifter, and push both simultaneously to shift the front derailleur.

Brakes

wilier cento 10 air shimano dura-ace direct mount brake

Direct mount brakes are more aerodynamic and give better performance

The most common brakes found on road bikes are cable-operated calipers that engage with the wheel rim. Recent advances have seen the introduction of hydraulic calipers, although these are not widely used, and an increasing number of road bikes are being equipped with disc brakes.

>>> Disc brakes: everything you need to know

Disc brakes are now UCI-legal (meaning they can’t be ridden in UCI road races) – yet surrounded by much controversy after riders have claimed cuts and lacerations have been caused by the rotors. For those riding outside of the peloton, but they can offer much improved braking power and modulation. In addition, because the wheel rim does not have to be reinforced to feature a braking surface, the rim can be lighter. Direct-mount calipers are also being seen in increasing numbers and offer superior performance to single mount calipers, but they are only compatible with specific frames.

Chainset

campagnolo chorus crankset

Chainsets with a number of different chainring combinations

Chainsets housing the front gears can be split into two main categories – doubles and triples.  A double has two chainrings while a triple has (you guessed it) three.

Double chainsets are available in different ratios, with 53/39t being the standard combination favoured by road racers (for those new to cycling, the numbers refer to the number of teeth on the chainring and the bigger number, the bigger the gear.  A bigger front gear is harder to push but can achieve higher speeds).

>>> Is it the end for the 34t chainring?

Compact chainsets have a 50/34t ratio and are currently the most common gearing equipped on road bikes.  The smaller 34-tooth chainring makes this kind of chainset ideal for riding in hilly terrain.  A third, increasingly common ratio known as mid-compact, with a 52/36 ratio, is also available, and is good if you want to be able to push a big gear down fast descents, but also want a small inner ring to fall back on in the hills.

Triple chainsets are being used less frequently these days, but they are often found on touring bikes as they offer the greatest range of gears, which is useful when riding a bike laden down with heavy kit.  The most common ratio is 50/39/30t.

>>> Are shorter cranks better?

The chainset also features the cranks, which attach to the pedals.  The length of the crank arms can vary, typically ranging from 160mm to 180mm.  The length of the cranks that come fitted to a complete bike is usually related to its size — for example, a 56cm frame will often have 172.5mm cranks.  Longer cranks offer a bigger mechanical advantage and larger effective gear, but can be harder to turn.  Shorter cranks are sometimes favoured in criteriums, as they offer more ground clearance to let you pedal around corners.

Cassette

thomas voeckler BH ultralight evo tour de france bike shimano dura-ace di2 cassette chain 11-23t

You can change get cassettes in different sizes to suit the sort of riding you’re doing

The cassette refers to the collection of sprockets on the rear wheel.  These are available in wide range of different ratios. An 11-speed cassette will have 11 sprockets on the cassette, which can be arranged in a close ratio such as 11-23t, which will be good for time trialling and racing on flatter terrain, as the close gears allow for fine adjustment and very smooth shifting, or a wider ratio like 11-32t, which gives you more gears to choose from when riding in hilly terrain.

You can change your cassette and it is common for cyclists to own a few different ratios. However it is important to remember that the size of the biggest ring on a cassette is limited by the length of the cage on the rear derailleur, so check with your local bike shop before you splash out on that 32-tooth granny gear!

Chain

alberto contador specialized s-works tarmac k-edge chain catcher

Chains come in different widths depending on the number of gears

The type of chain is dependant on the range of gears, i.e. a 10-speed groupset requires a 10-speed chain.  An 8-speed chain is considerably wider than an 11-speed chain. More expensive chains feature alloy coatings that are more resistant to wear, and are often lighter. Chains, like cassettes, wear over time, so will need to be replaced periodically.

Derailleurs

campagnolo potenza rear derailleur 11

The rear derailleur is arguably the most important component of a groupset

The derailleurs (also called mechs) are responsible for guiding the chain from one sprocket to the next.  A cable is usually responsible for the shifting, but electronic groupsets, such as Shimano Ultegra Di2, SRAM Red eTap, or Campagnolo EPS, use small motors to move the derailleur.  Front derailleurs are either band on, or braze on, so make sure you select the correct option if purchasing separately from your frame.  Band on refers to a circular clamp to attach to the frame. This is not always possible, as bike frames are not always round.  To counter this, braze on derailleurs are riveted or bolted to the frame.  The more expensive rear derailleurs feature ceramic bearings in the jockey wheels.

Electronic vs mechanical shifting

The Revelator Prestige comes with a full Dura Ace Di2 groupset

Electronic groupsets set the gold standard in shifting speed and precision

If you’ve got more than £3,000 to spend on a new bike then you will likely be faced with a choice of whether to go for electronic or mechanical shifting. Which you choose to go for depends really upon what you’re priorities are and the sort of riding you do.

>>> Six reasons why electronic groupsets are better than mechanical

For out and out performance, electronic groupsets are the natural choice, as shown by the fact that all but a handful of riders in the professional peloton now choose to use it thanks to the slightly sharper shifting and the ability to shift through multiple gears at once. And don’t be put off by the fact that the batteries have to be recharged (once in a blue moon) or the idea that it might be susceptible to the elements (in fact we’d argue that gear cables are much more vulnerable to wet and muddy roads and electronic wires).

>>> Six reasons why mechanical groupsets are better than electronic

Of course there are still many benefits to mechanical groupsets. The shifting on most mechanical groupsets is still very good, and if something goes seriously wrong then it’s much easier to be fixed than electronic. But perhaps most importantly, it’s also considerably cheaper, with the Shimano Dura-Ace Di2 costing £1,000 more than standard Dura-Ace, while Campagnolo Super Record is a massive £1,200 dearer.

What do you get for your money when buying a road bike groupset?

Groupsets vary in price a great deal, but what changes as the price goes up?  The first thing to consider is weight.  A lighter bike will accelerate faster and climb quicker than a heavy one, but components also need to be strong and stiff. As the price of components increases the weight decreases.  In order to maintain strength, durability and stiffness of the lighter components, more expensive materials are required. For example, an entry level groupset will likely have a steel chain, with a top end groupset featuring a titanium chain.

Performance

Manufacturing tolerances are much more higher on a top end groupset, which means that with an increased price, you get improved shifting between gears.  More expensive components are smoother, more precise and quicker to shift. Electronic groupsets are currently the benchmark in shifting performance, offering smoother shifting when changing gear under load, such as when riding out of the saddle or grinding up a hill.  In these situations the lower end groupsets will be very clunky and strained, whereas the electronic shifting is sublime.

Something to consider is that the shifting performance does tend to level out for the top two tiers. For example, the shifting quality between Ultegra and Dura-Ace is very similar, and the difference between the two primarily comes down to weight.

Braking performance also improves as the price goes up, with the calipers becoming stiffer up the hierarchy. This translates to more power, feel and modulation. The more expensive chainsets tend to be lighter and stiffer too. This can transform a bike, as a stiff crankset is more efficient at transferring the power from the pedals into forward motion. A chainring that flexes slightly under load will absorb energy, and decrease shifting performance too.  For these reasons the big sprinters, such as Marcel Kittel will favour very stiff chainsets.

Durability

As one would expect, durability generally improves as you move up in price.  Quality mid-tier components such as shifters and derailleurs last a very long time if properly maintained. However it is important to consider that the top-tier groupsets, such as Super Record and Dura-Ace, are not designed for workhorse everyday use. These components are designed to be the lightest, with everyday use a secondary concern, which means that durability of groupsets tends to peak around the second highest tier.  Running costs should also be factored in, as chains and cassettes are expected to wear out and be replaced several times throughout the lifetime of a bike.  Replacing a Super Record chain and cassette will incur a much greater cost than a Chorus equivalent.

Key groupset brands

The big three are Shimano, Campagnolo and SRAM – we’ve got dedicated guides on each of these:

There are a couple of other options:

Rotor road bike groupsets

Rotor uno groupset rear derailleur

Rotor Uno will be available to buy soon

Spanish manufacturer Rotor has long been making cranksets and power meter, but has recently unveiled it’s first groupset, the Rotor Uno hydraulic groupset. This groupset uses hydraulic fluid to move the derailleurs (and brake calipers) rather than cables or wires. The result is an exceptionally light groupset, although we haven’t yet been able to get our hands on one to put through its paces.

FSA road bike groupsets

Another newer name that is also set to join the groupset market is FSA. Best known for its cranksets and finishing kit, the Italian company has developed the K-Force electronic groupset.

Top Tips when looking at road bike groupsets on built bikes

When buying a bike look at the components it comes with. It is common for bike manufacturers to supply a bike with a whole groupset, minus the brakes and chainset.  These are sometimes (but not always) swapped out for cheaper parts to bring the overall price of the bike down. If you are unsure, enquire to establish what you are getting.  In some instances it can also be worth investing in a quality frame with a lower end groupset, with a mind to upgrading the components at a later date.