Cycling Straight Downhill: What Can Go Wrong (And How To Make Sure It Doesn’t)

February 22, 2023 0 Comments

View downhill on a long, straight country road

For a cyclist, few aspects of the ride are as highly rewarding as a steep downhill descent. After a lot of climbing, the freedom of a long downhill drop is exhilarating.

“You cover ground quickly — it’s exciting, and you don’t have to work hard,” says longtime cycling coach Darryl MacKenzie. “You can end up coasting, literally and figuratively.”

But with that reward comes a good deal of risk. There’s enough that could go wrong on a fast descent that many cyclists take them too cautiously and miss out on all the fun. But it doesn’t have to be that way. If you know what you’re up against, you can go in prepared to take the hills like a champ. 

To help you do that, we talked with Coach Darryl about six risks cyclists face on a fast, straight downhill descent. Here are his solutions for each one.

You Could Go Off the Road

The first — and perhaps biggest — fear in any cyclist’s mind is the thought of going off the road. That’s especially true if you’re descending a hill with a big drop-off along either edge of the road or coasting with an especially strong side-wind. You could hit something or skid out, lose control and slide or tumble off the edge, and the results could be disastrous.

Coach Darryl’s solution for this issue is to be alert to what’s ahead so that nothing catches you by surprise. Whether it’s a sudden turn or an obstacle in the road, you need to spot it well before you catch up to it. 

“You want to be able to identify any hazards far in front of you so you have plenty of time to slow down and stop or gradually steer the bike around them,” says Darryl.

To keep alert to any potential hazards, Darryl recommends using the “Rule of Two-Thirds.” In short, three- or four-second increments, spend two-thirds of your time scanning the road 100–200 feet in front of you, and spend the other third scanning for anything you might have missed from far out up the road toward the front of your bike. As you see potholes or other road hazards, slow down and veer gradually and gently around them. Watch the path around the hazard rather than looking directly at it, so you don’t drift right toward the danger inadvertently. 

You Might Fly Over the Handlebars 

When you’re going 30-plus miles an hour downhill, things happen fast. Especially if you haven’t been scanning ahead to stay alert, it’s easy to overreact and brake too quickly or too firmly. And when you brake hard at that speed, you’re liable to send yourself flying over the handlebars and tumbling downhill. 

The key here is to brake gently and gradually — to, as Darryl puts it, “feather the brakes." Start with your rear brakes, as the front ones are much stronger and more likely to send your body forward even when the bike is stopping. As you begin to slow down, you can gradually apply the front brake, until you eventually apply even pressure to both once you’ve reduced your momentum significantly. 

A Car Could Hit You From Behind 

Although you’ll go quite fast when cycling downhill, you’re still not as fast as a car. Vehicles will pass you from behind, so it’s important to be aware of them anytime you think about moving into their lane.

That said, it’s not safe to continually look back over your shoulder when you’re racing downhill. Your eyes should always be on the road ahead, and for that, you’ll need a mirror. This simple, inexpensive piece of cycling equipment is one of the most important things you can buy, and you should always have one attached to your helmet. Darryl recommends the Take a Look mirror. 

Use your mirror to take quick “flash-looks” behind you, especially before entering a motor vehicle lane and as you continue to ride in the path of potential traffic. Peek for a second, then look back to the road ahead as you process the information. If you realize the path is clear, you can take the whole lane. Otherwise, be sure to pull completely out of the way if there is traffic approaching.

You Might Collide With Another Cyclist

Cars aren’t the only major road hazard on the downhill. You also have to consider other cyclists. That’s true not only for the ones riding in front of you, but any cyclist passing on your side.

When it comes to cyclists ahead of you, spacing is critical. You’d be surprised how much ground you can cover in a second when you’re racing downhill on a bike. For every mile per hour of speed, you’re moving 1.5 feet per second. So, if you’re traveling 30 miles per hour, you’ll cover 45 feet in just one second. If the cyclist in front of you slams on their brakes, you could be headed for a collision very quickly. 

The point? 

“Allow more space than you think you need,” says Darryl. “Get many bike lengths in between you and anyone in front of you.”

As for cyclists beside you, it’s important to realize that this can be equally dangerous. Coach Darryl even knows of one rider who died in a side-by-side collision going downhill. Be sure not to make any quick movements or jerk around objects in case a cyclist may be passing on your left. 

You Could Lose Balance or Control

Balance is always important on a bike, but that’s especially the case when you’re racing downhill. You have to position yourself for maximum stability. That means keeping your pedals parallel to the ground and lowering your center of gravity. To do that, you should shift your butt as far back on the saddle as you can, leaning your upper body down toward the handlebars.

It’s very easy to create turbulence when you’re coasting at high speeds on a bike, and that can also throw off your balance. Your goal should be to cut through the wind and give it an easy path around your body. Leaning forward helps, but you should also be sure to tuck your knees in toward the top tube. This helps you slice through the wind and avoid making your body into a parachute that bounces in the breeze. 

You May Lose Your Grip

If you do hit a bump in the road on the downhill, it’s not necessarily a disaster. But it could quickly turn into one if you lose your grip on the handlebars. Suddenly, a small bump turns into a serious accident when you slip off the handlebars and go tumbling down.

To ensure that doesn’t happen, remember one thing: Always use the drops downhill. Never keep your hands on top of the handlebars or even on the hoods, as it’s far too easy to slip in either position. With your hands in the drops, you’ll be set to maintain your hold even when you hit a big bump in the road.

There’s always risk involved when you’re cycling downhill. But none of these risks is insurmountable. When you go in prepared, you can relax, stay alert and enjoy the ride. 

For more cycling safety tips, keep up with our blog and subscribe to our newsletter. You can always find more insights from Coach Darryl over at his website.


Image by Larisa Koshkina from Pixabay