If you’re in the market for a new bicycle, one of the smartest things you can do is familiarize yourself with the different groupsets on the market. A groupset is comprised of the mechanical components on a bike — excluding the frame, fork, stem, handlebars, saddle, wheels and tires. The groupset is somewhat like the drivetrain of a car, but including brakes.
Road bikes and mountain bikes have essentially the same components that make up their respective groupsets, but each is tweaked to favor the terrain and needs of the rider. The groupset market is dominated by two main manufacturers, Shimano and SRAM. In the world of road bicycle groupsets, a third manufacturer, Campagnolo, adds a storied history and aficionado-level parts into the mix. With a working knowledge of groupsets, you’ll be able to get the most out of your ride, whether commuting to work or climbing the switchbacks.
Groupsets
Weighing the Cost, Assessing the Quality
When purchasing a groupset, price is affected by two elements: weight and quality (durability). As a rule of thumb, when the prices goes up, the weight goes down. Excluding top-tier racing parts, groupsets become more durable the more expensive they get. For the best racing components, durability is overshadowed by the need to shed weight — in other words, the highest-end products will break down faster, but offer top performance when in good shape. Personal taste comes into play when deciding which groupset to purchase, considering the way a rider interacts with the groupset — especially the shifters. Also, there is a certain feel associated with each brand: Shimano feels smoother and SRAM has a definitive “click” into each gear. Campagnolo is on the snappy side, with characteristic “touchiness.” One is not particularly better than the other in terms of performance — it’s more personal preference.
For the serious rider: Upper mid-level groupsets offer the best durability-to-price ratio. They have similar technology to the high-end components (the previous year’s top-tier technology often trickles down) but are ever so slightly heavier.
For the focused amateur or commuter: Mid-level groupsets should be effective without breaking the bank.
For the beginner or occasional fair-weather rider: The groupset on your bicycle will be sufficient and effective.
Road
Top to bottom, moving from Entry, Mid, Upper-Mid, to Pro.
Mountain
Top to bottom, moving from Entry, Mid, Upper-Mid, to Pro.
The Individual Parts
More Than Just a Cog in a Crankset
The Crankset
A crankset is made up of one or more chainrings which are attached to crank arms. The pedals are attached to the cranks, but aren’t considered part of the crankset. Crank sizes can relate to frame sizes or be adapted to terrain needs, and range from 160mm to 185mm.
Road: The most common crankset for road bicycles is a 50/34 ratio, referred to as a compact chain set. The numbers refer to the amount of teeth on each ring (the big and small ring, respectively). The smaller the number, the easier it is to rotate the petals. Also available for road bikes are the larger 53/39 sets used by road racers (bigger number = faster speeds) and the 52/36, mid-compact.
Mountain: These days, the most common mountain bike crankset is the 1X (pronounced “one-by”) — a simpler setup with just a single-ring crankset ranging from 30 to 38 teeth. This setup ensures no dropped chains in rough riding and a lighter overall groupset. There is also a “double” setup, or a two-ring crankset, with the smaller inner ring ranging from 24 to 28 teeth and the larger outer ring ranging from 36 to 42 teeth. The smaller inner ring makes steep hill climbs on rough terrain much easier. Some entry level mountain bikes have three rings, giving a much wider range of gears but adding additional weight. The largest ring is often 42 or 44 teeth, the middle ring is 32 or 34 and the smallest ring is 22 or 24.
The Cassette
The cassette, or cogset as it’s sometimes called, is the set of sprockets that attaches to the hub of the rear wheel.
Road: For road bikes, the number of sprockets in a cogset can range from 8 to 11, and the teeth on those cogs can range in number from 11-23 to 11-32. The smaller the range, the more fine-tuned the shifting, where a wide range lends itself well to more varied terrain. The cassette works in reverse of the crankset, where bigger teeth numbers make the riding easier, smaller teeth numbers more difficult (but, of course, faster).
Mountain: For mountain bikes, the number of sprockets typically ranges from 8 to 10 and can have a tooth range of 11-32 (34 or 36 can also appear on the larger sprockets).
The Chain
The size of a chain depends on the size of the cassette and crankset. As the price goes up, chains are made of better materials and are coated to last longer. To cut down on weight for high-end chains, the pins are hollowed out. Because it’s the item that gets the most wear and is often the first replaced, a quality chain and careful chain maintenance is an important part of a groupset.
How to Maintain Your Chain: After each ride, it’s good to wipe and/or brush down your chain. If it’s light, warm conditions, that’s probably enough for a daily ride. But, weekly (depending on number of rides), it’s good to use a degreaser and brush to remove grit from the chain. After degreasing, apply a lubricant to the chain, one link at a time. Chain lubes vary depending on road and mountain and general ride conditions — it’s good to talk to a local shop about your particular lubrication needs.
Two Derailleurs, Front and Rear
The derailleurs move the chain across the rings of the crankset and across the sprockets of the cassette. Each brand has its own style, but the function is essentially the same. High-end derailleurs are made of carbon fiber and recently, on top-tier groupsets, shifting is not done with the traditional cable connected to the shifter — instead, it’s electronically actuated. This method is controlled by a battery and evens out shifting, especially in tough situations (read: difficult hill climbs).
Brake Levers and Shifters
The most variability in groupsets comes with the user interface: the shifters. For road bikes, brake levers and shifters are integrated into a streamline system where for mountain bikes, brake levers and shifters are separate entities.
Road: Shimano offers an integrated lever system with a paddle for shifting situated behind the brake lever: Swing the brake lever inwards and shift to an easier gear. Use the paddle behind the lever and shift to a harder gear. The right hand controls the shifting for the cassette and the left hand controls the shifting for the crankset. SRAM also utilizes an integrated system with a paddle behind the brake lever, but this paddle controls both up- and downshifts (it is dubbed “Double Tap”). Push the paddle until there is one click and shift to a smaller-sized gear, but push the paddle until there is a second click and the chain will shift onto a bigger gear. Campagnolo’s integrated system utilizes a paddle situated behind the brake lever and a smaller button-shaped paddle situated on the inside of the brake hood (rubber housing): The paddle will shift to easier gears while the button shifts to harder gears. Campagnolo’s technology allows users to switch through multiple gears at a time based on how far they push the lever or how many times they push the button.
Mountain: Shimano offers a trigger-based shifter with an upshift trigger operated by the index finger and a downshift trigger operated by the thumb. The rapidfire design used in the Shimano shifter allows users to shift up to three gears at a time with the thumb, depending on how far they push the trigger forward. SRAM offers a trigger-based shifter where both upshift and downshift triggers are operated by thumb. They also offer a gripshift shifter, which allows riders to shift multiple gears at a time by twisting the shifter either forward or backward.
Brakes, Front and Rear
The standard for many mountain bikes and road bikes was the cable-operated rim brake. Though these brakes are still standard on most road bikes (and the only type of brake approved for racing), disk brakes have become the norm for mountain bikes and are offered for a variety of road bikes, too.
Mechanically operated disk brakes, where a cable controls calipers that clamp onto a disk situated on the wheel’s hub, are entry level. Most high-end disk brakes are hydraulically operated, much like the brakes on your car.
