Why the surface deserves attention
A car passes over a pothole or a patch of gravel with barely a bump. A bike, with two small tyres and a rider balanced on top, is much more sensitive. A hole can bend a wheel or throw a rider off, a slick patch can slide a tyre out, and a hidden edge can snag a front wheel. The common thread is that most surface hazards are far easier to handle when you see them early.
This article is a field guide to the usual suspects and what each does to a bike. No list can cover everything, and conditions vary by place and season, so treat it as a starting point for your own observation.
Potholes and broken edges
Holes and cracked patches are the classic hazard. They can pinch a tyre against the rim, damage a wheel, or simply jolt the bars from your hands. Water can hide how deep a pothole is, so a puddle in a rough road deserves caution. Edges of repairs, utility trenches and raised or sunken sections can catch a wheel too.
If you can see a hole in good time, a gentle change of line around it is best, provided it is safe to do so with traffic behind. If you cannot avoid one, slow before it, keep the bike upright and your arms and legs soft so the bike can move beneath you. Avoid braking hard right at the point of impact. After a heavy hit, a quick look at your wheels and tyres is sensible, as covered in tyre inspection.
Drain covers and gratings
Drain grates come in different designs, and some have slots that can trap a narrow wheel. Metal covers can also be slippery when wet. Where a grate runs along the road, avoid crossing it at a shallow angle; cross squarely if you must. Drains also tend to sit in low spots where water, leaves and grit collect, so the area around them is often rougher than the rest of the road.
Gravel, sand and grit
Loose material on a hard surface acts like tiny ball bearings under a tyre, and it generally reduces both braking and turning grip. It tends to collect on corners, at junction exits, along the edges of roads and where side roads or driveways meet the street. Fresh surface treatments can leave loose chippings for a time.
On loose patches, reduce speed beforehand, keep the bike upright, avoid hard braking, and steer gently. Gravel-specific advice is in gravel road basics and loose surface braking.
Painted lines and markings
Painted lines, arrows, crossings and symbols can be slippery, particularly when wet and especially when you are leaning or braking. Because they tend to be at junctions, bends and crossings, they often sit exactly where you need grip most. Cross them upright where possible and be gentle with the brakes. The visual clues for low-grip surfaces are explored more fully in slippery surface clues.
Debris
Debris includes glass, thorns, nails, tyre fragments, bits of wood, fallen branches, dropped loads, litter and even animal remains. Larger items can bring a rider down; smaller items cause punctures. Debris often accumulates in the part of the road that cars rarely pass over, such as the edge or the bike lane, and can hide under leaves. After storms, check more carefully.
Fresh debris on busy roads can appear without warning, for example when a vehicle sheds something. Looking well ahead and watching what drivers ahead do, such as swerving, can give you a clue.
Kerbs, ramps and level changes
Raised kerbs, dropped kerbs that are not flush, speed bumps, tram or railway tracks and bridge joints can all upset a bike. A kerb struck at a shallow angle can deflect a front wheel. Cross rails and grooves as squarely as you safely can, with the bike upright. Speed bumps and humps are generally best taken slowly, with your weight lifted slightly off the saddle and arms relaxed.
Cobbles, uneven paving and rough ground
Cobbled streets, loose paving slabs and uneven ground can be bumpy and slick when wet. Look at rough ground and cobbled streets for more detail. A little more width in your tyres and a relaxed grip generally help, but the main thing is to slow down and keep your line steady.
Wet, fallen leaves and ice
Seasonal hazards such as damp leaf litter, frost, snow and ice need extra attention. These are not always visible, so the sensible approach is to slow down in uncertain conditions and keep the bike upright. Wet road traction is generally lower than dry, as outlined in wet road traction.
What to do when you see a hazard
- Look early and keep scanning. Don’t fixate on the hazard itself; look at the clear path you want to take. Eyes tend to pull the bike toward what they stare at.
- Check behind before you move. If you need to move around a hazard, glance back, as described in shoulder check, and do not swerve into the path of a vehicle.
- Slow down smoothly, and do it before the hazard, not on it.
- Warn others. In a group, point or call out a hazard so those behind can react, as described in calling out hazards.
- Report serious problems to the relevant local authority if there is a way to do so, because large holes or damaged surfaces can hurt others.
Build the habit
Spotting hazards is partly a matter of knowing what to look for and partly of practising looking. On familiar routes, it can help to note the recurring problem spots and plan for them. If a hazard catches you out and leads to a fall, review what happened without blame, because it is a way to learn, and consider common crash causes for patterns that crop up often. Wear a helmet, carry the basics for a flat, and ride within your comfort, as conditions can always surprise you.