Disc brake road bikes are simply road bikes that come with disc brake
technology. Having been used on
mountain bikes for many years, this disc brake technology is now being
used on Road Bikes. And not just high
end models as brands have identified the advantages for all road riders.
With the trickle down affect, this technology is now appearing on entry level road bikes. Our buying guide to
disc brake road bikes will help you decide on the best bike for your needs.
Rim brakes have been the defacto standard for many years, with the braking force as the name suggests applied
to the wheel rim. The brake calipers clamp to the rim and the force
applied allows you to slow or stop
altogether. With disc brakes the force is moved away from the rim to a dedicated braking area, namely a
separate rotor fixed to the wheel hub.
The obvious difference is the wheel rim serves as an integral component of the wheel, an area that the tyre
is fixed to and then your braking force applied to. With disc brakes this force is applied to a different,
smaller area.
The other major difference is how the brakes are operated. Rim brakes are connected from the lever to the
caliper by a cable. You pull on the lever and this in turn pulls the cable which closes the caliper on the
rim. The majority of disc brake bikes available use a hydraulic braking system. The cable system is replaced
by a hose connecting the lever and the brake which is filled with non-compressible fluid. So when the lever
is pulled the pressure forces the fluid into the caliper.
This has the effect of pushing the pistons in and the caliper outwards, making the brake pads grip the rotor.
A more affordable version of disc brake technology is the cable activated option. Rather than using
hydraulic fluid to activate the pistons it similar to rim brake as it works using a cable.
Disc brake equipped road bikes do not have to be complicated or expensive. The cable activated version has
cheaper parts and more widely available parts as there is more compatibility between brands.
There is the additional ease of maintenance at home or on the roadside. Hydraulic versions are more widely
available and given the success of this technology on mountain bikes which are generally ridden in
conditions far worse than road bikes, that has to be a big plus.
The most noticeable difference occurs in the amount of effort required to bring your bike to a stop. Disc
brakes have the advantage of offering a huge amount of stopping power. In all honestly more than most riders
will need but it means less effort is required to bring the bike to a standstill. This would be extremely
useful on long descents. With this amount of stopping power it is useful for larger riders or heavier bikes.
Using disc brakes provides the rider with a more even application of braking power so a rider can gauge how
much pressure is required in most situations. This last factor can be extremely useful in wet, grimy
conditions. With traditional rim brakes, the brake pad has to first displace any water or grime from the
road before biting on the rim. This can cause a ‘lag’ before the speed is scrubbed off, which can be a
little disconcerting at the best of times. This is more pronounced when using carbon rims.