 Better road surfaces
Motorcycles by the very nature that they have only two wheels are more susceptible to difficulties and hazards created by the design, construction, maintenance and surface condition of roads. Road based hazards can be categorised as:
- Permanent characteristics of the road surface — roughness, being an unsealed or gravel road, low skid resistance, tramlines, railway lines, painted lines on roads
- Temporary characteristics of the road surface — potholes, surface irregularities, pit lid covers, oil or gravel on road, debris, gravel, melted tar in hot weather, roads that become greasy and slippery in summer during rainstorms (Allardice, 2002)
- Visual obstructions — stationary vehicles, vegetation, fog and heavy rain
- Characteristics of the road alignment — horizontal curves, vertical curves.
While road based hazards can, in some cases, cause loss of control of the motorcycle, their role is more often contributory when the motorcycle is performing a complex manoeuvre such as turning or braking. For example, a motorcycle braking heavily to avoid colliding with a car turning left across its path may be unsuccessful if the motorcycle had not crossed a manhole cover with an inch high asphalt beam around it which caused the front wheel to lock up and slide out, throwing the rider and passenger to the ground.
Haworth (1999) reported the results of the site inspections and ride-throughs conducted for the Case-Control Study of Motorcycle Crashes (Haworth et al., 1997). This provided an opportunity to assess whether the road conditions or the surrounding environment contributed to the occurrence or severity of the crash. In 31 cases (15% of inspected sites) it was found that the road surface actively contributed to the occurrence of the crash. In many other cases the variables were present at the crash site but did not actively contribute to the occurrence of the crash. In 47% of cases, no site factors were judged to have contributed to the occurrence or severity of the crash. The most common site factors were: lack of visibility or obstructions (20%), unclean road or loose material (14%), poor road condition or road markings (12%), and horizontal curvature (12%).
Better road surfaces provide an opportunity to prevent motorcycle crashes. The extent of the likely benefits depends on how much resources are devoted to such improvements and how much riders behaviour adapts to the better surfaces. If better surfaces lead to higher speeds, then some of the benefits may be dissipated.
Information sourced from A review of potential countermeasures for motorcycle and scooter safety across APEC (Full report and References [PDF, 304KB]). |
