Colnago C59 Hydraulic Operated, Radially Mounted Caliper - Image Courtesy Roadbikereview
From the conversations I have engaged in with manufacturers,
shops, mechanics and riders, it looks like the lines have been clearly drawn -
Rim brake vs. disc brake. The rim brake
has been around a long time, is simple and reliable, however, it is not the
most efficient method of stopping a bicycle wheel. The disc brake has all of these qualities of
reliability and simplicity as well, but it is an incredibly efficient way to
stop a bicycle wheel.
For the record, I hate to call the rim brake a caliper brake
(as many people do), as disc brakes have a caliper, too.
I always knew discs were the way to go, and I
have been a vocal proponent for a long time.
What really got me to put fingers to keyboard on the subject was an
article on the
Colnago C59 in the November 2012 edition of
Bicycling Magazine.
The article makes a good case
for road discs, and it also made a good read of the C59, as well.
However, where the article went off the proverbial rails a
little bit were in the areas of the
UCI “Evaluating the benefits of road discs,”
and the perceived issue of “Boiling brake fluid.”
While the former is preposterous, the latter
is complete nonsense.
Brembo Radially Mounted Caliper, With Carbon Pad-Carbon Disc Setup On A Honda RC212V
Case in point: If
MotoGP World Champion Casey Stoner can
haul his Honda RC212V, 1000cc motorcycle down from 200 MPH, with Carbon rotors
utilizing carbon brake pads, all without burning up his brakes or boiling the
fluid, then how on God’s Green-Earth can even a 200 pound bicyclist produce
enough energy to induce the opposite?
Whether a hydraulic or cable-actuated bicycle disc system, there simply
is not enough energy to completely fry your brakes – In my opinion.
As for the UCI, if safety is so paramount (as the article
stated), then why in the heck have discs not yet been thoroughly evaluated and
standardized? In this regard, I
completely concur with Ernesto Colnago that this is, above and beyond all, a
safety issue. And, who would know better
than Mr. Colnago?
The article also alludes to some kind of mythical “Learning
Curve” with this new, never-before seen technology (heavy sarcasm
intended). Please, are riders really that
dumb? In fairness to the articles
author, well if someone is, then they best not be riding a bicycle outdoors
without a helmet and an airbag.
Almost everyday now, one can read about a new road-going
disc brake technology leap. It is clear
they work, the know-how is there, and they are a need waiting to met by road
riders world-wide. When viable disc
systems can meet, or slightly exceed, weights of equivalent rim brake systems,
well, the proverbial writing is on the wall.
And now for the really good part.
Not only will safety be improved by stepping
into the modern era, but so will the issues of
“Exploding” carbon clinchers and unreliable
braking be solved forever.
However,
safety rarely trumps economics.
Don’t
think so?
I have spent a fare share of
my career in aviation, and the only way an improvement became adopted was
through some sort of tragedy.
This is
not to foolishly claim wheel manufacturers are evil, diabolical murderers.
It is just they have so much money and time
invested in rim brake research, which disc brake technology will completely
wipe out.
So, do not expect wheel
manufacturers to go oh-so boldly into thy disc-laden good night.
To add a bit of relevance, I have been riding motorcycles
for over thirty-two years. A few of
those years were spent racing, thus I have a pretty go handle on the dynamics
of braking (more on this in a bit). Meanwhile,
on my road bike on long descents, I have noticed I often end up alone out front
rather quickly. Upon polling fellow ride
participants, and evaluating my own riding, I have discovered a few interesting
things. One, most people are terrified
of descents, compounded with a definite fear of the front brake. This, in turn, leads to a near constant
application of both brakes, which is very hard on wheels, especially carbon
clinchers. And finally, some old habits
are hard to break (no pun intended). I
tend to use the brakes on my bike the same as I do on a motorcycle – The less
braking the better, and when I do need to brake, it is a last second, hard,
modulated application to set my corner entrance speed. And contrary to popular belief - You can
indeed brake all the way to the corners’ apex.
SRAM Red-Black Rim Brake Mounted On A 2010 Trek 2.3
I believe the rim brake had long ago reached its potential,
and the disc will offer a lot more than the obvious superior braking
power. And, the debate over weight and complexity will eventually sort
itself out. Clever folks are already adapting
new technologies and will apply it to yield light, powerful braking systems,
allowing at long last, wheels with lighter rims, negating the heat and poor
braking issues with carbon.
In regards to application engineering, radially mounting the
calipers will yield exceptional strength and balanced braking forces, plus more
even pad wear. Of course, forks and
chain/seat stays will all have to be beefed up as the additional forces in
these areas will have to be dealt with.
The weight and balance of the bike and braking forces will all become
homogenous with the benefits of centralized mass, and improvement in the moment
of inertia. In plain English, these are
all good things.
I used to think the people most resistant to change were
pilots and novice computer users. Well,
if cyclists are indeed resistant to change to disc brakes as the article
suggests (and my informal rider polling indicates), they will indeed be left
behind.
Especially going down hills.