The market shares are clearly distributed. The Japanese company Shimano produces and sells by far the most bicycle parts worldwide. It is followed by SRAM (USA) and Campagnolo (Italy). SRAM is a driver of innovation, for example with wireless shifting. The Americans are good at doing things differently. With aggressive marketing, they sometimes steal market share from Shimano - most recently in mountain biking, where they were able to establish the single drivetrain without a front derailleur as the new standard. The traditional Campagnolo brand exclusively manufactures road bike and, more recently, gravel bike components; however, the parts are rarely found on production bikes, which is more due to price and distribution structures than to the function and quality of the products. The market shares also reflect how cost-efficiently the manufacturers can produce. Shimano has strong roots in manufacturing technology, maintains numerous plants in many countries and is pushing ahead with automation. This makes it possible to produce competitively even in the high-price country of Japan.
High overall quality level at Campagnolo, SRAM and Shimano
Shifting and braking works well with all groupsets, the overall quality level is very high. The gradations between the groupsets are barely noticeable in terms of function, especially with the electric drivetrains. The comparatively inexpensive Shimano GRX Di2 and SRAM Rival AXS electric drivetrains are also excellent. More expensive parts are above all lighter, more elaborately designed and sometimes also more durable.
The transition between components for gravel bikes and road racing bikes is fluid. For gravel bikes, many manufacturers tend to use cranks with just one chainring, but Shimano also offers the option of two chainrings with its versatile GRX gravel groupset. This is ideal for athletes whose gravel tours involve a lot of tarmac or predominantly flat routes.
Configure as required
The desired configuration can be achieved by skilfully combining parts from different groups of a manufacturer, because the components of a brand with the same number of gears, the same actuation (electrical, mechanical) and the same brake system are usually compatible. However, the capacity limits of rear derailleurs must be taken into account. Two details are important here: the largest sprocket that the derailleur can handle and the capacity of the derailleur to absorb chain length differences. The tooth differences of the sprockets and the front blades are added together. For example, 50/36 results in a difference of 14 teeth; an 11-28 cassette adds 17 teeth difference, totalling 31 teeth capacity.
Compatibility
The decision in favour of a particular component brand has a long-lasting effect. This is because parts from different brands can hardly be interchanged or combined with each other.
The individual parts of a brand can be combined with each other within certain limits. This can be interesting, for example, to use wearing parts such as the chain or sprockets from a cheaper groupset with a higher quality drivetrain. Swapping between brands only works in isolated cases; ten and eleven-speed sprockets from Shimano can be combined with ten/eleven-speed drivetrains from SRAM, for example. However, the shifters and brake levers from Shimano, SRAM and Campagnolo cannot be interchanged. The rotors on which the sprockets are mounted are also different. Shimano's road bike components use the HG standard with sprockets mounted individually or in small groups, even for the new twelve-speed gradation. The XD road rotor from SRAM is not compatible with this. Campagnolo rotors are available in two widths; the narrower rotor of the Ekar gravel bike groupset also harmonises with older Campa road bike groupsets. Outside the Campagnolo world, the rotors are rare. Shimano and SRAM rotors, on the other hand, can be found on many wheels. They can often be changed simply by repositioning them.
Spare parts
Road bikes are usually ridden for many years and even more kilometres. It is therefore important to be able to buy spare parts for as long as possible:
- Campagnolo: Experience has shown that the spare parts supply is exemplary; many individual parts are available, the central service centre is considered helpful - also for private customers. Long product cycles. The spare parts list and prices can be found at www.campagnolo.com.
- Shimano: Experience shows that this is largely unproblematic; large range of parts sold via Shimano service centres. On the Shimano website you can see which spare parts are available for each component. https://si.shimano.com
- SRAM: In our experience, not very service-friendly. Spare parts are rare and expensive. Damage or wear to expensive individual components (sprocket set milled from a single piece) results in a new purchase. Power meters that have to be disposed of or replaced at the end of the battery life illustrate the philosophy of the Americans. www.sram.com
Road bike gears in comparison
Three manufacturers, three different ways of switching - either mechanically or electrically:
The Bowden cable is a proven, inexpensive and reliable technology for transmitting signals or power - but it is also sensitive and subject to wear. Electronic shifting systems make many things easier and safer for manufacturers, mechanics and road cyclists, which is why they are steadily gaining market share. Among the top groupsets, only Campagnolo still offers the option of manual shifting. Shimano will at least continue to offer the mechanical eleven-speed Ultegra after the introduction of the electronic twelve-speed Ultegra as long as there is demand.
Electric gearsticks are easier to operate, which is their biggest advantage for the user. The gears change foolproof via touch buttons, nothing grinds or rubs and no shift cable gets tangled. Once set up correctly, the gear shifting works with lasting precision - or not at all, i.e. digitally. The front derailleur with servo motor also shifts more crisply and reliably than even the most experienced hand can. Further advantages: You can attach additional shift buttons almost anywhere on the handlebars and programme them individually. On modern frames with internally routed cables, electronic shifting (and hydraulic brakes) are almost a must. Bowden cables would have to be routed at such an angle that their function would suffer. The power supply for the components is solid and usually lasts for many hundreds to thousands of kilometres. The central battery from Shimano lasts twice as long as the decentralised batteries from SRAM.
SRAM transmits the shifting commands directly to the derailleur, while Shimano transmits them from the grips of the new Dura-Ace to the central battery, which is wired to the rear derailleurs. Campa uses the same wiring throughout. The advantage of wireless is the uncomplicated assembly of the individual parts. In addition, the cable is no longer a potential weak point in the event of a fall or transport. The stand-by discharge of the Campagnolo battery is annoying, but this can be prevented with a magnetic strap around the seat tube.
The front derailleur
Shimano and Campagnolo have greatly simplified shifting with the electric front derailleur: The gear changers are energetic and reliable. The front derailleurs from SRAM can also do this, but are much more complicated to adjust in comparison. The Force AXS derailleur in particular is almost impossible to adjust satisfactorily without specialised knowledge. Consequence: Noise or chain dropping.
Cost trap?
A broken Bowden cable can usually be replaced easily and for little money. If the electrical system goes wrong, it's usually a matter for the workshop - which can be time-consuming and expensive. According to our observations, Shimano's Di2 is robust and has always been so. Failures are quite rare. The picture is worse with SRAM. The first generation of eTap had frequent failures and many derailleurs had to be replaced. The second generation (eTap AXS) seems more reliable, but is still relatively new. In our experience, Campagnolo's electronic EPS shifting works reliably. Nevertheless, the purchase and follow-up costs for electrical parts are significantly higher than for mechanical components. If an electric series is discontinued, the spare parts situation can quickly become precarious.
Road bike brakes in comparison
Disc brakes - the new standard: Disc brakes are still a hot potato among racing cyclists - much criticised because of their extra weight of at least a pound and the fact that they are perceived as more complex to maintain and care for.
Manufacturers are pushing disc brakes, and many new bike models are now only available with discs. However, with the new Dura-Ace, Shimano still offers the option of continuing to use the rim brakes of the previous generation - a farewell in instalments. In principle, hydraulic disc brakes all work in a similar way. The master cylinders are built into the shifters and the brakes are usually fitted with 160 millimetre diameter discs, sometimes also with 180 millimetre discs, which are better able to withstand heat, and rarely with 140 mm discs, which must also be considered undersized for road bikes. Campagnolo and Shimano use hydraulic oil as a medium, SRAM uses dot brake fluid.
Practice check
In practice, we have so far liked the Campagnolo brakes best, they are quiet and powerful and easy to adjust. Shimano's lightweight Ice-Tech discs have two faces: great at low to medium speeds, problematic under extreme loads. The discs can grind and ring after hard braking, and they can occasionally become irreversibly deformed by the heat generated during braking. The brake pads are very close to the disc, which makes adjustment difficult. (With the new Dura-Ace, the distance has been increased). The bleeding procedure is fiddly and time-consuming, and the variety of different pads and discs that influence braking behaviour is difficult to keep track of. Professionals often use stiffer mountain bike brake discs to reduce the problems. These have now been integrated into the new Dura-Ace. SRAM's brake disc is heat-resistant, but often squeaks in the wet; the pads wear very quickly and tend to lose braking power (fading) due to heat when new. However, bleeding is quite simple. Discs are clearly superior to rim brakes on wheels with carbon rims, but the advantage over aluminium rims is less clear. In case of doubt, they even have a higher thermal stability than the rather small brake discs on road bikes. On the other hand, tyre bursts due to overheating are a thing of the past with discs.
TIP: If you assemble your bike yourself, rim brakes make it lighter and cheaper.
TIP: Gravel bikes that are to be used a lot on difficult and steep terrain should definitely have brake discs with a diameter of 180 millimetres!
Translations
One or two chainrings? Tightly stepped gears for smooth pedalling or giant sprockets for steep climbs? Modern road bike drivetrains can do many things - the perfect gear ratio for everything and everyone is available.'s but unfortunately still not.
Road: Gear ratios on the road bike
Road bike transmissions are traditionally finely stepped; in the fast gears, the aim is for the adjacent sprockets to be one tooth larger or smaller. This enables smooth cranking at high speeds. On the other hand, the transmission should enable all types of uphill riding, which requires large sprockets with many teeth, with which the ideal of the one-tooth jump cannot be realised. Reconciling both requirements therefore requires compromises, even if there is room for eleven or even twelve sprockets on the rear wheel these days. This is because only a widely spaced cassette offers real mountain gears, but is automatically more coarsely spaced. Additional variables are the chainrings, which are available in various gradations, from very mountainous (small number of teeth) to giant ratios for flat professional races. In principle, anything is possible. What is best for whom is a question of performance and the route. Marathon bikes usually come with compact cranks and the 50/34 chainring combination, which, in conjunction with cassettes from 12-32 teeth, cover a very wide range and offer almost a 1:1 ratio for steep climbs. Gear reductions are also possible. The classic 53/39 (or 52/36) transmission with 11-28 teeth, which offers longer gears and finer steps, is intended for racing.
SRAM is downsizing the sprockets and chainrings of its AXS groupsets across the board. The sprockets start with 10 teeth, the compact chainrings have 46/33 teeth, the racing ratios 48/35 or 50/37.
In order to optimise the gearbox, it is worth taking a look at the speed at which you drive most often. The finely graduated long gears are often in a speed range in which you rarely ride. Shimano has therefore made the 16-speed sprocket an integral part of the new twelve-speed Dura-Ace, which was missing in many gradations and stands for fine connections in the range between 35 and 40 km/h - a frequent road bike speed on flat terrain.
Off-road: Gear ratios on a gravel bike
Shimano riders have the choice between double and single cranks in off-road terrain; the Gravel group GRX offers plenty of options here. Which is better depends on what you mainly want to do with the bike. Roughly simplified: In demanding terrain, a single-speed gearbox has advantages because all gears are in series and are easy to shift. The best offer for this is Campagnolo with the 1x13 groupset Ekar; the range corresponds to a wide-ratio 2x gearbox, the fast gears are finely stepped. The jumps in the uphill gears are comparatively coarse, which a 2x11 gearbox can do better.
With the XPLR rear derailleurs and the corresponding cassettes, SRAM creates for the Red, Force and Rival groupsets, new single drivetrains for gravel bikes with cassettes of 10-36 or 10-44 teeth. The maximum bandwidth (440 per cent) remains below that of the MTB groupsets, but the gearing is more finely graduated. XPLR drivetrains are compatible with the XDR freehub body.
All complete road bike groupsets at a glance
Campagnolo Road
Campagnolo Gravel
Shimano Road
Shimano Gravel
SRAM Road
SRAM Gravel
Legend: M=mechanical gearstick; E=electrical gearstick; F=rim brake; D=disc/disc brake
Notes on all prices: For Shimano's new Dura-Ace 9200 and Ultegra 8100, the list prices are given for the versions with disc brakes at market launch. All other prices correspond to the average sales prices of the most favourable configuration (mechanical/rim brake, if available) from various online providers (as of August 2021).
