When I set people up on their bikes I set them up to hold onto the drops. I make the point that most of us want to go as fast as we can for the amount of effort that we want to put in. Even at easy efforts you’ll go faster if you’re more aerodynamic, and what’s the point in having an aerodynamic position if you can’t use it for more than a few minutes at at time?
Of course you can get very aero positions by holding the hoods. Just as aero and efficient as on the drops.
But a good position on the drops isn’t just about being aero.
It’s by far the best position for stopping and slowing down quickly. And therefore the best position for descending and cornering fast – as those both involve braking, ideally as late as possible to lose as little speed as possible.
The drops are obviously a good position for braking – assuming that the brakes are set where you can reach them – but why is holding the hoods such a bad position for braking?
With your hands on the drops you squeeze the brake levers towards the bars. You use your strong finger (or maybe the strongest two) and you pull perpendicular to the lever and close to the end, where you have a good mechanical advantage. With your hands on the hoods, however, you can’t actually squeeze the brake levers. You either have to lever them with your strong fingers or pull them towards the hoods (i.e. with an oblique force rather than a perpendicular one) using your weak fingers. That might sound a bit convoluted – but the picture above illustrates it quite nicely. With your hands on the hoods you simply cannot apply much force to the brake levers. That means you cannot safely allow your speed to build up because you are not in control. If that does not sound scary, it should. And if it doesn’t feel scary to you on the bike it can feel pretty scary to those around you.
But that’s not all…
When you do apply the brakes the bike slows down. Quite quickly – even if you’re holding the hoods. You, on the other hand, still have the inertia that you had before you applied the brakes so you’ll carry on moving forward unless something slows you down. It won’t be the saddle (unless it has a deep dip in which case it can slow you down by applying force to your genitals) so you’re left with your hands and your feet. Your feet can only help if you can push back on the pedals – or at least on one of them. You can only do this if your heel is below your toes and your centre of gravity is behind the pedal. The way that I set people up on their bikes permits this, but a typical Retul fit for example, or a time trial fit does not. That leaves just your hands and arms to stop you sliding off the front of the saddle when you apply the brakes.
But if your hands are on the hoods and trying to apply the brakes they’re full of tension and the mechanics of your brake-squeezing action are tending to lift them and slide them forwards over the hoods! So now, in addition to a death grip to squeeze the brakes you’re using the same grip to stop yourself shooting over the front of the bike.
I could go on…
With your hands and fingers squeezing the hoods and the levers to both slow the bike and prevent yourself shooting off the front you can’t modulate or control the pressure on the brakes. Furthermore your bodyweight, with all of its momentum, is pressing heavily on the bars and the front wheel so you can neither control your steering nor absorb any road shock through your elbows. If you hit a bump or a slippery patch you’re likely to bounce or skid. And if you weren’t in control when you took off what are the chances of you being in control when you land?
Bike fitting and set up isn’t just about aerodynamics and power. And it isn’t just about comfort and injury prevention. It’s about control too.
What about disk brakes? One argument used in favour of disk brakes on road bikes is that they are more powerful and allow better modulation. My experience of rim brakes, however, is that the liming factor is tyre grip rather braking power or modulation. I fear that disk brakes give a false sense of security to people riding on the hoods that they can slow down and stop quickly. Sure, they can slow their bikes down quickly, but that can have disastrous consequences if they’re not holding on to them.