7.4 Surface Hazards and Mechanical Problems While Riding

Surface Hazards and Mechanical Problems While Riding

Motorcycle tyres have small contact patches, so a short strip of gravel, oil or paint can affect both tyres at once. The first defence is early observation. Look well ahead, choose a cleaner path and reduce speed while the motorcycle is upright. Once on the hazard, keep controls smooth and avoid asking the tyres to brake, accelerate and turn sharply at the same time.

Common surface hazards

Loose gravel, sand and roadworks: slow before the loose material, keep the head up and arms relaxed, use smooth throttle and steering, and allow the motorcycle small natural movements without fighting it. Increase the gap from other traffic.

Wet paint and metal: road markings, covers, plates and rails can be slippery when wet. Cross as upright as practical with steady controls. Where a rail or groove must be crossed, use a sufficiently direct angle to prevent the tyre tracking along it, but do not make an abrupt 90-degree swerve into traffic. The safe angle depends on the road and available space.

Oil, diesel and bitumen: look for sheen, staining and spills near intersections, roundabouts and fuel locations. Avoid them where possible. Reduce speed before the contaminated area; do not brake or accelerate sharply on it. Hot-weather bitumen can soften, but no single friction value applies to every repair.

Potholes, corrugations and edges: choose a path early. If a sharp obstacle cannot be avoided, slow beforehand, approach as squarely as traffic permits and keep the motorcycle stable. Be careful when moving from a sealed surface onto a shoulder: check for a drop at the bitumen edge, sand, mud and a safe stopping area.

Wobble

A wobble may be caused by speed, load distribution, tyre condition, pressure, bearings or another mechanical problem. The guide advises:

• keep a firm grip without locking the arms or fighting the steering;
• gradually roll off the throttle;
• gradually apply the brakes and move to the roadside; and
• identify and fix the cause before continuing.

Avoid an abrupt steering correction or acceleration. A motorcycle that has wobbled needs inspection, not another high-speed trial.

Skids

Remove the cause. If excessive braking locks a wheel, ease the brake so the wheel can rotate and reapply smoothly after stability returns. If acceleration or speed causes the skid, ease the throttle and slow. Prevention—appropriate speed, smooth inputs, sound tyres and adequate space—is safer than relying on skid recovery.

Puncture or blow-out

A flat front tyre can make steering heavy; a flat rear can make the back weave. Keep a firm grip and travel straight. Avoid brakes if possible. If braking is necessary, use the brake on the tyre that remains sound because braking the failed tyre can separate it from the rim. Move weight back for a front failure or forward for a rear failure, roll off gradually, then coast to a safe roadside stop.

Stuck throttle

If the throttle sticks:

1. pull the clutch in to disconnect drive;
2. apply the brakes progressively and move to the roadside;
3. use the engine-stop switch; and
4. turn off the ignition.

Keep steering control and do not reach for the key in a way that locks the steering. Do not restart until the cause is repaired.

Broken clutch cable, chain or seized engine

With a broken clutch cable while moving, slow and downshift as speed permits, selecting neutral before stopping. If stopped with the clutch engaged, hold the brakes to stall the engine.

A broken chain may leave the motorcycle freewheeling or may lock the rear wheel. If it freewheels, roll off, brake smoothly and move roadside. If the rear locks, steer into the skid, roll off and coast roadside as speed falls.

If an engine begins to seize, loss of power or an abnormal sound may provide warning. Pull the clutch to disconnect the engine, brake smoothly, move roadside and switch off. Allow it to cool and have the cause corrected; merely adding fluid is not proof the motorcycle is safe.

Emergency roadside exit

Check the shoulder surface, mirrors and blind spot; signal; leave at an appropriate speed; and stop well away from traffic. Mud, sand, a steep drop and the bitumen edge can turn the exit into a crash. Make the motorcycle visible without standing in an active lane.

The knowledge-test response is consistent: smooth control, reduce drive, preserve direction, stop safely and fix the cause before riding again.