What is a road bike?

The anatomy of a road bicycle

Road bikes, or racers as they are sometimes referred to, are speed machines – bicycles designed to take you as far and as fast as your legs can manage. The road bike gets its name from the terrain it is designed to be used on; yes, you guessed it, tarmac.

At first glance, the road bike hasn’t changed a great deal over the years. Compared to complex full suspension mountain bikes, it’s a traditional bicycle with a near identical silhouette to those raced 50 years ago. Of course, there’s nothing traditional about the carbon fibre frames and electronic 22-speed drivetrains we see now. The technology is here, you just have to look closer.

It’s important to know your way around a road bike in order to get the best from it. While the overall shape has changed little, the details have moved on a lot. The most important aspect is how the bike fits you. If you get that right at the start, everything else will be simple.


The frame is the heart of any bike, and road bike frames are usually aluminium or carbon, with steel and titanium used in niche models. 

Traditional road frames use a flat top tube and a shorter seatpost, but compact geometry is now most common, with a sloping top tube to make a smaller, lighter frame and also improve the standover height. It’s very important that you buy the right size and shape frame for your size and riding.


Road bike wheels don’t have to be as robust, so they use fewer spokes than mountain bike hoops. Aerodynamics are important, so the rims are sometimes deeper. Recently, road rims have been getting wider as research shows this is more aerodynamic, increases tyre volume for a smoother ride and potentially leads to less flats.

Road bike tyres are also skinny, typically 23-25mm wide, with older racing tyres going down to 18mm. To minimise rolling resistance these tyres usually have a slick centre stripe and run at high pressures of 6-8 bar (90-120psi). Like rims, a recent trend in road tyres is to go slightly wider for a smoother and more confident ride - 25mm width are quickly becoming the replacement standard from 23mm.

Wheels: wheels
Wheels: wheels


Road bikes traditionally feature two chainrings, with tall 53/39T combinations on race bikes. More usable 50/34 compact setups are now popular to aid climbing. There is also the new 'semi-compact' standard of 52/36T, which aims to offer the high end speed of the race gearing with the easy climbing of a compact.

Triple chainsets are optional on some cheaper bikes, and give the widest range, with a small inner ring - although these are quickly becoming less popular with the lighter and simpler compact taking over. 

Chainset: chainset
Chainset: chainset


Road bikes use gears that are more tightly packed together to help you pedal at the ideal speed (cadence). Most road bikes, apart from entry level ones, now have 11 sprockets.

Cassette: cassette
Cassette: cassette


Dropped handlebars mark out a road bike, and offer a number of positions. The tops, with your hands either side of the stem, are used for steep climbs or cruising. The hoods are the brake lever covers, and provide a comfortable stretch and good leverage for climbing out of the saddle. The drops are the lower parts of the bar, used for a lower position at speed. 

Bar width and shape varies to tailor your bike’s fit to you. The set in the picture below is an anatomical fit, with a straight section in the drops for a more natural grip.

Handlebars: handlebars
Handlebars: handlebars

Saddle and seatpost

As you would expect, these parts have a big impact on the comfort of your ride. For road bikes especially, comfort is more dependent on correct set up than it is on having lots of padding. 

Road saddles are generally long, narrow, thin and sparsely padded. They look very uncomfortable, and do take some getting used to, but are actually better than overly soft deep saddles for long rides of several hours. Recent research has shown that saddles should fit with your sit bone width, so many brands are now offering various saddle widths.

Seat and saddle: seat and saddle
Seat and saddle: seat and saddle


Road bikes use dual-pivot brakes, although disc brakes are beginning to make an entrance on some models. Dual-pivot brakes are compact, light and powerful, but are only suited to road riding because they have no mud clearance at all.

Brakes: brakes
Brakes: brakes

Getting started

A decent entry-level road bike can still be purchased without doing too much harm to your wallet – you just have to know what you're looking for. We've compiled a list of the best cheap road bikes, plus the best road bikes under £1,000 and under US$1,000.

Once you've bought your bike, you can use our workshop to find out how to improve your ride comfort in 10 steps.

This article was published by BikeRadar, the world's leading source of bike reviews, gear reviews, riding advice and route information
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