FINDING THE HIDDEN BENEFITS IN COMMUTER MOTORCYCLING

WHERE THE COSTS AND BENEFITS FALL

For the motorcycle commuter, there are user benefits that result from their choice of transport - they enjoy riding, it’s faster than driving, it’s cheaper, etc. The costs are well known. Putting aside the user benefits, and reasons, for or against, why some people choose motorcycle commuter travel, it has been argued that a motorcyclist’s contribution to the wider commuter community results in a net social dis-benefit. That is, in high income countries where few people choose to use this mode, motorcycle road accident costs are significant and disproportionately higher than most other means of transport, and in some cases, motorcycle environmental and commuter costs are also higher than car commuters per person kilometre travelled.

However, poor policy analysis has misrepresented commuter motorcyclists. A focus on road accident costs in policy analysis has positioned motorcycle commuting as problematic, producing more costs than benefits. A better approach to understanding the costs and benefits of motorcycle commuting is needed. This is particularly important as some costs (and benefits) fall on all road users. An example of a cost that falls on all road users might be public expenditure for the deployment of policing and emergency response to road users, particularly related to accidents.

Now, the individual that chooses to ride a motorcycle to work or school most likely has little interest in this type of argument/analysis. Fair enough. But the people that make decisions on government policy and public infrastructure investments certainly do and their decisions can negatively impact motorcyclists.

The rest of this article is a very quick look at a recent 2011 study on the changes to traffic congestion and vehicle pollution that results from increasing motorcycle modeshare (the proportion of motorcycles compared to all other modes of transport) on a section of a congested motorway in Europe. The Study attempts to estimate the benefits of motorcycle commuting, looking at the gains all commuters can receive from increasing motorcycle trips on a congested motorway. The gains include reduced travel times, lower vehicle operating costs, and improved environmental conditions. This type of analysis shows motorcycle commuters have the potential to produce network wide benefits, improving the daily commute for all road users. It is also a more balanced and comprehensive type of analysis.

The study is very technical, employing complex traffic planning methodologies to model vehicle travel and driver behaviour. Its findings are interesting, if a bit dry and academic. However, motorcyclists should be encouraged by the Study’s findings. The full report can be found here (Commuting by Motorcycle: Impact Analysis, 2011).

A BRIEF SUMMARY OF THE STUDY

The study area covers a motorway route between Leuven and Brussels, in Belgium. A computer traffic model is used to simulate and analyse the changes in traffic congestion resulting from a theoretical modal shift in commuter traffic from cars to motorcycles. Assumptions are made that all the additional motorcycle traffic will come from car drivers, not public transport users or car passengers. No other modal shifts are modelled such as changes to public transport patronage, although generated/induced traffic (i.e. new trips attracted to the road) is taken into account. The traffic model generates traffic flows on a computer network of the motorway for the morning peak commuter period from 6.30 a.m. to 9.30 a.m. A reference scenario based on the current observed motorway traffic is established, modelling the 2011 motorway traffic flows, intersection queues, and dispersal of queues. Analysis of key factors like changes in travel time are calculated by comparing the off-peak un-congested motorway with the peak period congested motorway to establish indicators to judge how well the motorway is functioning. For example, one indicator used in the study is lost time due to traffic congestion, defined as “the difference between the observed actual travel time and the travel time in an uncongested network with free-flowing traffic.”

Analysis of motorway traffic statistics and other data showed 83.4% of vehicles on the motorway were classified as small private vehicles with motorcycles comprising 0.9% of this group. For the model shift scenario (to test the effects of greater motorcycle use), the Study authors “assume that 10% of the cars are replaced.” Motorcycles were expressed in terms of passenger car equivalents (PCE):

“When there is little traffic on the road, it can be expected that motorcycles will take up as much space on the road as cars. A motorcycle then has a PCE value of 1. However, when the road becomes busier, and the speed of the traffic flow falls, motorcycles take up less space. Some motorcycles keep less distance from the vehicle in front or ride between two lanes. The passenger car equivalent of the motorcycle is consequently reduced. When traffic comes to a complete stand still, it can be assumed that all motorcycles drive between two lanes. In this case, the motorcycle has a PCE value of 0. The PCE value of a motorcycle is therefore dependent on the speed and the traffic situation on the road. Furthermore, the PCE value is also dependent on the type of road (motorway, regional road, crossroads, etc...) and on the number of motorcycles in the traffic flow.” (p.19)

The Study authors found that “[c]ompared to the reference scenario, the modal shift scenario including knock-on effects shows a reduction in lost vehicle hours of 40%.” Knock-on effects (e.g. generated/induced traffic) refers to additional trips attracted to the motorway that result from the improved traffic situation. When 10% of all private cars were replaced by motorcycles, there was a reduction in traffic congestion, travel times reduced, and total travel time for all vehicles decreased by 40%. A modal shift of 25% from cars to motorcycles would be required in order to eliminate traffic congestion completely and achieve free flow traffic conditions.

Additional analysis on the modal shift scenario looking at environmental impacts through vehicle emissions found that “[t]he total external emission costs of motorcycles (4-stroke, ≤ 250 cc, emissions class Euro 3) is 21% lower than that of an average car.” (p.36) For total vehicle emissions, the modal shift scenario is 6% lower than in the reference scenario. So more small capacity motorcycles also reduces overall vehicle emissions. However, it should be noted vehicle emissions analysis is a complex and difficult field for transport research.

No analysis on road crash costs is provided in the study. Analysis of other complex transport related influences, such as land use changes and sensitivity to changes in operating costs (fuel prices, etc), was also not reported.

WHERE TO NOW

For high income countries, little empirical evidence is available to support the wider, external benefits of a greater motorcycle modal share of commuter traffic. This study shows that under certain circumstances (e.g. a congested road where lane splitting is allowed) wider network benefits can theoretically arise from more motorcycles on the road.

Although quantifying the effects of commuters switching from cars to motorcycles on a congested road network is a complex issue, this study shows simple arguments based on myths, beliefs, and ‘educated’ guesses are not sufficient for evidence based, robust policy analysis. It would be foolish to argue this study refutes a belief that the commuter motorcyclist is a free-loader, one not bearing the full costs of their choice of transport. However, it does provide strong evidence that motorcycling is more than the sum of individual, personal user benefits. When a car commuter switches from their car to a motorcycle we should not automatically assume a net negative outcome for the community. Nor assume the fewer motorcycle commuters the better.

Studies that provide evidence of network benefits, like reduced traffic congestion and lower vehicle emissions, that result from an increase in motorcycle commuter trips will help planners and policy makers better understand the role of motorcycles in the transport system. These benefits are network wide and accrue to all road users, not just motorcyclists.

When judging the value of any study a good maxim is don’t confuse a metric with reality. Sure, this study provides interesting findings. It seems logical that commuters switching, in significant numbers, from a single occupant car to a motorcycle would reduce traffic congestion. It attempts to quantify the external benefits of such a modal switch. However in the real world, where policy makers deal with difficult expenditure decisions on transport infrastructure, manage complex community issues and often competing public demands (e.g. finding solutions on road networks for widely diverse users such as cyclists through to freight movers), the role motorcycles can play is often seen as minor and negative. If a city has transport objectives to reduce traffic congestion through, for example, improving public transport and promoting modal shift away from low occupancy cars, and these objectives most often come with significant public expenditure, then promotion and policies supporting increased motorcycle use may be seen by public officials as problematic, even counter to their stated transport objectives. It’s clear to see there’s no easy solutions here.

The key take away for high income countries, particularly for their transport policy makers, is motorcyclists need to be properly included in transport policy. As professionals, they should be able to do this.