RoSPA – 3. Motorcycle Accidents & Casualties

3.1 Despite forming only 1% of road traffic, motorcyclists account for 14% (one in seven) of road deaths and serious injuries. However, casualties amongst motorcyclists have dropped significantly from their 1981-1985 average. As can be seen in Table 5, motorcyclist fatalities have fallen by 45%, serious injuries by 68%, and slight injuries by 57%. Overall TWMV user casualties have decreased by 60%.

TWMV Casualties in Great Britain, 1981/85 and 1999

Casualties19991981-85% Change
Fatal547989-45
Serious636119714-68
Slight19284444903-57
Total2619265193-60

3.2 Worringly, the number of motorcyclists killed rose by 10% between 1998 and 1999, the number seriously injured rose by 7% and those slightly injured by 6% . This may be due to a 16% rise in motorcycle traffic between 1998 and 1999, which means that the motorcycle casualty rate by distance travelled fell by 8%. However, caution should be used when interpreting trends from changes in accident data from one year to the next.

3.3 The vast majority (94%) of motorcyclist casualties are riders, with passengers forming just 7% of casualties. Casualty reductions in absolute numbers for pillion passengers have been even greater than those for riders.

TWMV Rider and Passenger Casualties in Great Britain, 1981/85 and 1999

Riders

Casualties19991981-85% Change
Fatal525861-39
Serious591817649-66
Slight1807339945-55
Total2451658455-58

Passengers

Casualties19991981-85% Change
Fatal22128-83
Serious4432064-78
Slight12114544-73
Total16766736-75

3.4 Casualty Rates
While some of the changes in motorcyclist casualties may be attributed to the fall in motorcycle use, the motorcyclist casualty rate per billion kilometres travelled in 1999 had also fallen by 26% from its 1981 – 85 level.

3.5 Motorcyclist casualty rates are much higher than other road users, as can be seen in Table 7.

Casualty Rates per 100 million vehicle kilometres by Road User Group, 1999

Road User GroupKilledKSIAll Severities
Pedal Cyclists4.17.6544
TWMV Riders11140533
Car Drivers0.33.435
All Riders & Drivers0.45.141

3.6 The casualty rate for motorcyclists is 15 times higher than that of car drivers, but similar to that of pedal cyclists. The fatality rate for motorcyclists is three times higher than for pedal cyclists, but 40 times higher than that for car drivers, reflecting the fact that motorcyclists are not protected by a vehicle body, seat belts or the other occupant protection systems that car drivers enjoy.

3.7 Vehicle Involvement Rates Vehicle accident involvement rates show that motorcyclists are more likely to be involved in accidents. Table 8 shows that motorcycles are seven times more likely to be involved in an accident than a car, and 14 times more likely to be involved in a fatal or serious accident.

Vehicle Involvement Rates by Type of Vehicle, 1999

Road User GroupFatalFatal & SeriousAll Severities
Pedal Cyclists4.580563
TWMV's13159592
Cars1.01187
All Vehicles1.21391

3.8 Motorcyclist Casualties by Age
There is a clear relationship between motorcyclist casualties and age, as can be seen in Table 9. There are few casualties below the age of 16 years because two wheeled motor vehicles are generally not used by children. Moped users show a casualty peak between the ages of 16 and 19 years. Motorcycle and motorcycle scooter user casualties peak between 20 – 49 years. These patterns probably reflect usage patterns of different types of motorcycles.

Motorcyclist Casualties by Age, 1999

  Moped UsersMotorcycle and Scooter Users
AgeKilledKSIAllKilledKSIAll
0-151266523993
16-1962661734385782415
20-2929657617017566527
30-3914430517320427225
40-49129190759213002
50-59225140293871314
60+43312519130412
All ages175273192508593721421

* Includes speed limit not reported

3.9 Motorcyclist Casualties by Gender
Motorcyclist casualties are predominately male. Men account for 93% of motorcyclist deaths and 88% of total motorcyclist casualties.

Motorcyclist Casualties by Gender, 1999

CasualtyMaleFemaleAll
Killed50839547
KSI62566516907
Total *23263292026183

 

3.10 Casualties by Location
Overall, almost three quarters (72%) of motorcyclist casualties occur on built-up roads (roads with a speed limit of up to 40 mph), even though such roads carry less than half of motorcycle traffic. The pattern differs for different types of motorcycle. Around 85% of moped and scooter casualties occur on built up roads, compared to around 70% of motorcycle casualties.

3.11 One quarter ( 26%) of casualties occur on rural roads (roads with a speed limit of over 40 mph). And just 1% of motorcyclist casualties occur on motorways, which carry 7% of motorcyclist traffic.

3.12 However, the pattern for motorcyclist fatalities differs: 60% of motorcyclist deaths occur on non built-up roads, 37% on built-up roads and 3% on motorways.

Motorcyclist Casualties by Type of Roads, 1999

RoadKilledKSIAll
Motorways16148458
Built-up Roads195344416039
Non Built-up Roads31927896503
All Speed Limits*530638123000

* Includes speed limit not reported

3.13 Casualty rates by distance travelled show that built-up A roads have a significantly higher rate for motorcyclists than other types of road, followed by built-up minor roads.

3.14 An analysis of motorcycle accidents in Cheshire indicate a shift in the balance of casualties from urban to rural roads, along with an increase in the proportion of casualties who are killed or seriously injured.

3.15 Motorcyclist Casualties by Month
Motorcyclist casualties are highly seasonal. Fatalities and overall casualties peak during the Spring and Summer months, which probably reflects increased riding, and hence accident exposure, during this period.

Motorcyclist Casualties by Month: 1999

MonthKilledKSIAll
January202991473
February213491438
March435312042
April515702072
May647402499
June546772459
July729142876
August716982552
September456552470
October515982420
November395482364
December163291527

3.16 Casualties by Time and Day
Fridays have the highest number of motorcyclist casualties, followed by the other days of the week which each have a similar level. The number of weekend casualties is slightly lower. During the week, motorcyclist casualties peak between the hours of 4:00 pm and 6:00 pm and between 7:00 am and 9:00 am. At the weekend, powered two wheeler casualties are more evenly spread throughout the day, with a slight peak between midday and 6:00 pm. This is similar to the pattern for all road users.

3.17 Road Surface Condition
Motorcyclists, being two-wheelers, are more susceptible to the condition of the road surface. They are more likely to skid on both dry and wet road surfaces, and in particular are put at greater risk by mud or oil on the road. Snow and ice seems to affect car drivers just as much as motorcyclists, although motorcycle use probably drops significantly when ice and snow make riding very difficult and unpleasant.

Percentage of Vehicles Skidding by Road Surface Condition: 1999

Road User GroupDryWet or FloodSnow or IceMud or OilAll Conditions
TMMV17.926.253.666.420.6
Cars10.418.649.552.314.3
All Riders & Drivers10.218.348.352.013.9

3.18 Motorcyclist Casualties by Manoeuvre
As with all road user groups (except pedestrians) most motorcycle accidents are listed as “Going ahead other”. However, 13% of motorcycle accidents are listed as “Going ahead on a bend”, compared to only 8% of cars. Similarly, 12% occur when the rider is overtaking another vehicle, compared to only 4% of car accidents during this manoeuvre. This may reflect motorcyclists’ greater vulnerability during these manoeuvres.

Motorcycle Accidents by Manoeuvre: 1999

ManoeuvreNumber
Going ahead other15980
Overtaking a moving or stationary vehicle3801
Going ahead on a bend3582
Turning or waiting to turn right1189
Waiting to go ahead660
Turning or waiting to turn left697
Stopping541
Changing lane311
Starting184
Parked60
U-Turning64
Reversing19
All known manoeuvres*27122

* Includes manoeuvre not reported

3.19 Almost one in five (18%) motorcycle accidents involve the motorcyclist losing control, without any other road user being involved. The equivalent figure for cars is 14%. However, not all loss of control accidents are due to rider error; deceptive bends, poor road surfaces and avoiding other road users also are a factor in a proportion of these accidents.

3.20 The Booth report, published in 1989, assessed nearly 10,000 motorcycle accidents in the Metropolitan Police area. It concluded that nearly two-thirds (62%) of motorcycle accidents were primarily caused by the other road user. Half of the accidents were caused by car drivers, and 10% by pedestrians. The report found that two-thirds of motorcycle accidents where the driver was at fault were due to the driver failing to anticipate the action of the motorcyclist.

3.21 In contrast, the analysis of motorcycle accidents in rural Cheshire found that 67% of motorcycle accidents were due to rider error, with losing control on a bend and overtaking featuring strongly.

3.22 Motorcyclists and Drink Driving
There is little difference in the rate of breath test failures between motorcycle riders and car drivers.

Breath Tests: 1999

Road UserNo. Involved in RTANo. Tested (%)No. FailedFails as % of InvolvedFails as % of Tested
Cars329866175916 (53%)66692%3.8%
TMMV2712212970 (48%)4431.6%3.4%

3.23 However, a lower proportion of motorcyclist fatalities (9%) were over the drink drive limit than car driver fatalities (16%). And the percentage of TWMV rider fatalities who were over the drink drive limit has fallen considerably more than the equivalent figure for drivers.

Percentage of TWMV Riders and Motor Vehicle Driver Fatalities Over the Legal Blood Alcohol Limit: GB 1988-1999

YearRidersDrivers
19882320
19892118
19901918
19911720
19922617
19931520
19941822
19951521
19961323
19971319
19981117
1990 Provisional figures920

 

3.24 Motorcyclist Injury Patterns
Various studies have assessed the types and frequencies of injuries to motorcyclists. Legs are the most commonly injured, followed by the head and arms.

Proportion of Injuries to Motorcyclists

Site of Injury% of all Injuries
Legs39%
Head23%
Arms19%
Shoulder/Thorax10%
Abdomen/Pelvis7%
Neck1%

3.25 Around 80% of motorcyclist casualties suffer leg injuries, 56% suffer injuries to the arms and 48% to the head. However, head injuries are usually more severe than those to the legs or arms, and account for 80% of motorcyclist fatalities. Injuries to the thorax and pelvis are infrequent, but usually severe.

Proportion of Motorcyclists by Injury

Site of Injury% of Casualties
Legs80%
Head48%
Arms56%

3.26 Head Injuries
Head injuries account for 80% of motorcyclist fatalities and can include cuts and abrasions, concussion, severe facial injuries, skull fractures and injuries to the brain. They appear to be more likely in crashes in which the motorcyclist collides with another vehicle at right angles and the head impacts against the vehicle, or in cases where the rider slides along the ground and strikes their head on a kerb or piece of roadside furniture. Skull fractures may occur at speeds of 30 km/h or more, but brain injuries may happen at much lower speeds, from 11 km/h upwards.

3.27 Leg Injuries
Leg injuries account for 60% of serious injuries and may include cuts and abrasions, fractures, broken bones and dislocated joints. The knee and lower leg appear to be the most vulnerable. Leg injuries are most frequently caused in accidents which involve the motorcyclist striking the side of a vehicle at an oblique angle, or a vehicle striking the motorcyclist side-on. The injuries are caused by a direct impact or the leg being trapped and crushed between the vehicles.