Bumps and potholes

The light construction of bicycles trades off against the possibility of damage from bumps and potholes, railroad tracks, rocks and roots… The tradeoff can be successful but, as with many other aspects of bicycling, your riding skills matter.

Your choice of a bicycle…

Let’s start with some good news.

Bicycles have pneumatic tires which can be squashed almost to the rim with no damage. The fabric of a tire flexes and the air inside compresses harmlessly, as this slow-motion video shows.

If bumps and potholes do not exceed the height of your rims above the ground, your ride may be jarring, but no damage will occur to them. Understanding this is key to whether you must slow down, ride around, jump, walk or carry your bicycle.

Fatter tires are more pothole-tolerant, and as recent research has shown, supple tires up to 47mm wide are as fast as skinny tires. While aerodynamic drag is higher, less energy is lost to vibration. Road bikes are trending away from frames and forks which take only the skinniest tires (and no fenders!). But you don’t necessarily need to buy a new bike to enjoy the advantage.

• Slightly smaller 650B wheels with wider tires could replace wheels with narrow 700C tires. You may have already dinged up the rims anyway! With disk brakes or drum brakes, the smaller wheels can fit without any other modifications. You’ll have to replace rim brakes.
• An older rigid-frame mountain bike can offer the advantage of wider tires at a lower price, and a moderate cost in weight. Good road tires are available in mountain-bike sizes, and there’s nothing wrong with equipping a mountain bike with road handlebars. Mountain bikes also come with a wider gear range than typical road bikes.
• Fatbikes and e-bikes can have tires as much as 5 inches (125mm) wide. A fatbike sacrifices efficiency in road riding; an e-bike compensates for that with the motor.

Steps

You can usually ride onto a low step — a steel plate at a construction site, railroad tracks, an uneven joint between concrete slabs, the rim of a shallow pothole — if you approach them squarely. You’ll want to stand up and use your arms and legs as suspension. Tires inflated hard have more bounce to surmount hazards, at the expense of a harsher ride. Do maintain a firm grip on the handlebars! Release the brakes momentarily to avoid locking or skidding the wheels as they lose and gain traction.

Drops

Dropping by a few inches, (typically, over a curb) doesn’t risk damage to the tires and rims. For comfort and to maintain control, you need to keep the cranks horizontal so you don’t catch a pedal, and rise off the saddle with the knees and elbows flexed.

Before descending a curb, you do need to check for conflicting traffic in the street.

A deeper drop could damage the frame and fork. Skilled off-road riders use some clever tricks to negotiate fallen logs and dropoffs, but we’re just covering what you need when riding on roads and paths.

Vigilance, vision training, good headlight

Bumps and potholes aren’t the only hazards. Pavement edges and diagonal railroad tracks can sweep your bicycle out from under you. We cover them in CyclingSavvy’s Train Your Bike sessions. And that is not to speak of sharp objects which can flat your tires — delayed misery.

Mostly, you avoid all kinds of road hazards through your skills. Keeping the eyes moving, and scanning the road surface every few seconds, are essential to avoid all of these hazards. I dinged a few rims before I got good at avoiding these hazards That was back in the heyday of skinny tires, though.

Peripheral vision can do more than provide semi-conscious cues. I trained myself over a period of a couple years to focus my attention in one direction while my sharp central vision looked in another. (Careful about doing this in company — it looks weird.) With practice, I learned to observe the entire visual field consciously. In that way, I could be give more attention to the road surface without losing awareness of traffic.This is literally consciousness expansion. And a rear-view mirror allows you to keep facing forward with more attention on conditions ahead.

Seeing conditions matter. The shadow under a tree can be especially difficult, and led to my worst crash. At night, a good headlight with a flat-topped beam pattern casts a long, even beam of light onto the surface ahead. A headlight mounted lower, at the fork crown or on a front rack, will reveal bumps and potholes better than one on the handlebar. And of course slow down if you aren’t sure that you can see well.

Value your personal space.

Perhaps it’s obvious, but your options to avoid surface hazards are much improved if you are away from the edge of the road. Again, a rear-view mirror is helpful. A glance into the mirror will reveal whether there is any traffic (bicycle or motor-vehicle) behind you, and afford you the confidence to use the space you need. If there is traffic behind, the mirror makes it easier to negotiate lane position.  

Keep your distance from any rider ahead of you who is not a trusted paceline companion. Many crashes on bicycle-club rides occur due to failure to point out a hazard. The same hazard occurs when riding close behind a motor vehicle, even at low speed.  

My worst experience with a pothole occurred when I was close behind another cyclist on a slow group ride. It cost me a concussion — 15 minutes of my life when I appeared and acted normal, but which I did not remember, followed by the disturbing realization that I did not remember my route home. Fortunately, my memory recovered within a couple hours. It could have been worse.

The rock dodge maneuver

If you notice a pothole soon enough, you can steer around it normally. Sometimes, though, you don’t see a pothole until you have almost reached it, or you are in a tight space. CyclingSavvy teaches the rock-dodge maneuver – steering quickly to one side (usually the left) to avoid a pothole, then regaining balance by steering quickly the other way.

This can be so quick that the bicycle just zigzags to one side, then the other, and you continue to ride in a straight line. It’s good to practice this in a parking lot, but it needs to be second nature when you see the hazard at the last moment. Sooner or later, a pothole will test you!

Jumping

Jumping over a pothole or other surface hazard is often possible. It can be useful when you have time to prepare, and as an alternative to the rock dodge. Clipless pedals or toe clips and straps offer an advantage in pulling up on the rear of the bicycle. Jumping is easiest on a lightweight bicycle.

A single jump works well if you are going fast. At slow speeds, you haul up on the handlebar first, and then lift the rear wheel. Timing is important, and it takes practice. Skillful mountain bikers accelerate to lift the front wheel, but you won’t need to do this in road riding.  

If bumps and potholes damage a tire or rim

The classic example of bump and pothole damage is the pinch flat, where the tire was crushed against the rim. It is also called the snake bite, because it leaves two holes in the inner tube.

Are tubeless tires the answer? They seal themselves against ordinary punctures. Mountain bikers like them because they can run at low pressure without getting pinch flats.

The sealant in a tubeless tire can create a mess though, if the tire comes off the rim. Removing and replacing a tubeless tire is messy too. You need to carry an inner tube, a tool to remove the special tubless-tire valve,and a pump (or a cell phone) anyway in case a tubeless tire does puncture. It’s your choice.

Impacts can damage a rim, too. It may be possible to pull out a minor dent in an aluminum rim, though that requires a special tool and good wheelbuilding skill. Repair is most likely to succeed with a low-profile aluminum rim. Never just tighten the spokes where the rim is indented – that indents it more.

If rim sidewalls were spread apart by the impact, rim brakes lurch. There’s no way to get the rim back to smooth braking, so it needs to be replaced. Fortunately, most aluminum rims these days have parallel sidewalls, and they usually do not spread when dinged.

Rim damage also loosens spokes. A disk, drum or coaster brake may offer a false sense of security when the rim is damaged. It’s best to check spoke tension, and err on the side of safety.

Carbon-fiber rims crack, and generally need to be replaced if damaged, though I have heard of their being repaired.

Bumps and potholes come with the territory

Bumps and potholes are an unfortunate fact of life, and I hope that I have been able to offer some useful advice!