The mechanical heart of your bike
The mechanical heart of your bike
The groupset or ‘gruppo’ is the collective term for the components on your bike that take care of gear shifting and braking.
As a result, the groupset is a key part of the make-up of your machine, alongside the frame itself and the wheels. In this buyer’s guide we’ll take a closer look at the groupset components, run through which manufacturers supply the mechanical heart of your bike and consider what you get for your money.
Component overview
The components of a groupset consist of a set of combined brake and gear levers, otherwise known as shifters. The chainset is made up of a crankset (to which the pedals, not considered part of a groupset, are attached) and the chainrings. The chainset spins on a set of bearings known as the bottom bracket.
The cassette is the cluster of sprockets housed on the back wheel and the number of sprockets determines the ‘speed’ of the groupset i.e. eight, nine, ten or 11-speed. Both the cassette and chainset are connected by the chain to drive the bike.
Front and rear derailleurs work in conjunction with the shifters to move the chain across the cogs and chainset as you pedal to select your chosen gear. The brakes, erm … brake.
The manufacturers
Shimano, SRAM and Campagnolo are the three big players that dominate the UK groupset market, though you’ll sometimes find a smattering of parts from other manufacturers when buying an off-the-shelf bike. These include FSA (chainset and brakes) and Tektro (brakes).
Back to the big three, and market share swings heavily towards Shimano – the Japanese firm supplies 13 of the 17 WorldTour teams, and you’ll find Shimano components on most off-the-shelf bikes – while SRAM and Campagnolo (Campag) sweat it out in Shimano’s wake.
All three manufactures offer a hierarchy of groupsets; this is based on manufacturing costs, material quality, performance, durability and weight. As you rise through the range, the use of more exotic materials means the weight (in most cases) will drop, and the performance (the precision and refinement of shifting, and braking performance, for example) will rise – as will the cost.
Although many components may look alike, there is little room for crossover between each manufacturer’s components. The only gap in this rule can be found in cross-pollination of some chainsets and cassettes.
You can’t mix-and-match the components of different speed groupsets either, i.e. you can’t put a ten-speed derailleur on an 11-speed bike and expect it to work properly.
With that in mind, let’s take a closer look at each individual groupset component.