It seems an awful lot of people don’t know how to use the middle pedal. “How hard can it be?” I hear you ask. Well, more difficult than you might think.
Some of us have experienced that awful feeling on a bicycle, when you cook the brakes going down a steep hill. Everything gets too hot and slowing down doesn’t really happen anymore. Some of us have experienced it in cars too. Tragically, it can happen with lorries and other heavy things.
I think the problem stems from a lack of understanding. Petrolheads know that a brake generates heat when applied. It’s pure energy conversion – slowing the car by producing heat. Naturally, car makers know this and braking systems are designed to let the heat escape. It’s one of the reasons disc brakes are better than drum – it’s easier for the heat to escape, so you can apply a stronger stopping force and not cook everything. Petrolheads also know that a binding brake can generate a LOT of heat. That’s like driving along with the brake gently applied. Even a short journey can generate enough heat that you can’t touch the wheel without burning yourself. It’s why I’ll often do a quick check of wheel temperature when I get out of a car, especially if it’s new to me.
So, I get rather horrified when I see cars going down hills with the brakes applied constantly. I can only presume that people don’t realise the danger they are exposing themselves to. Keeping pressure on the middle pedal means heat just builds and builds. If it gets bad enough, you can start to boil the brake fluid and cook the friction materials. Both with have a disastrous effect on your stopping power. If brake fluid boils, bubbles appear in the fluid and pressing the pedal squashes the bubbles rather than apply the brakes. If the friction materials get too hot, they just don’t work very well – what’s known as brake fade. With older cars, you really had to know not to cook the brakes. Modern cars are far better at venting heat even under difficult conditions. However, I would still recommend you review your middle pedal treatment.
It’s better to brake harder than you otherwise might, then come off the middle pedal. Brake in bursts, but ease off again to allow the brakes to cool. Even a second or two makes all the difference. Modern cars don’t have anywhere near the engine braking of older cars, so easing off the throttle and downshifting won’t necessarily be enough – you still should though!
Disaster averted. Just!
This technique saved me from total disaster in Snowdonia once. I was travelling far, far too quickly down a very steep hill in the 2CV. That was fine – the road was straight, visibility was good and the opportunity to race up to 60mph-ish like the car was supercharged was too much to resist. Thankfully, I realised that the road was going to get curvy, well before we got there. What followed was a truly bum clenching experience, as I began my on-off braking. Bends were approaching, I was still going too quickly, but I still forced my foot off the pedal, then back on. Trees were whizzing past and if anything, the hill seemed to get steeper, but I kept up my routine. Now the brakes were getting very hot. I could smell them. I could feel the fade effect starting to creep in. I kept coming off the pedal, for as long as I dared, before a brief application, then off again.
Braking performance was pretty poor by the time I got us slowed down enough for the first bend, but thank goodness I had! Had I just stood on the brake pedal and held it down until we’d stopped, I’m pretty sure I would have only succeeded in cooking the brakes entirely, before I’d slowed to a safe speed.
So, do have a think about how you brake. Remember to check your mirror before you do – in case someone is driving too close – and give your brakes an easier life. And for goodness’ sake, PLEASE don’t sit in traffic jams with your foot on the brake! That’s what your handbrake is for. Drive safe.