As the inner parts of Australian cities get denser and more congested, the cost of driving in terms of time lost in congestion is rising. Travellers are increasingly looking to alternatives to cars for travelling to work, school and other destinations.

They’re mostly turning to public transport and bicycles, but they’re also using motorcycles and scooters more. For example, the number of motorcycles entering the City of Melbourne in the morning peak increased 73% between 2006 and 2014, while the number of cars fell by 2%. (I use “motorcycles” to cover scooters, motorbikes and mopeds.)

It’s no accident that motorcycles are the mode of choice in cities such as Hanoi where the cost of driving is prohibitively expensive for most. In Australian cities, the attraction is down more to the cost of time lost in traffic than it is to low incomes; however, in both cases motorcycles offer a number of advantages over other modes.

They’re cheaper to buy, operate and park than a car and, because they take up less road space and can filter between lanes, they’re faster in congested traffic conditions. According to Melbourne City Council’s (MCC) Motorcycle Plan 2015-18:

“An Australian study…estimated that a 30km trip in metropolitan Melbourne can be three times faster by motorcycle than by car in peak hours.”

They also provide significant social benefits. They use less fuel than cars and hence emit less carbon, as “little as 1.3 litres per 100 km”. The Motorcycle Plan says they also reduce traffic congestion:

“A Belgian study found that a 10 per cent shift from cars to motorcycles could reduce travel time by an average 8 minutes for the remaining 90 per cent of drivers.”

It’s not just cars; motorcycles offer advantages over public transport too. The big one is that, like cars and bicycles, they’re a private form of transport. They’re available on demand; they travel directly and without stops; they’re not shared with strangers; and they can carry and store chattels.

All that makes them attractive to travellers, but they also have social benefits. They don’t require an operating subsidy from the budget; they largely use existing road infrastructure; and it’s likely their environmental impact per passenger kilometre is at least on par with that of buses and trains.

Motorcycles have some advantages compared to bicycles as well. They’re faster and so can travel longer distances (including on motorways); they’re harder to steal; they’re more usable by unfit and infirm travellers; they can carry a passenger and heavier goods; and riders don’t require a shower.

Motorcycles should have a large potential market in Australian cities because many trips are made solo e.g. the journey to work. They should appeal to the many travellers who want the flexibility of driving but with a lower penalty from congestion, operating and parking costs.

Despite their many advantages, motorcycles have drawbacks too. Discomfort due to weather is more of an issue than it is with either cars or public transport, and they don’t provide as much exercise benefit as active modes. Further, some larger motorcycles offer little environmental advantage over a small car and too many are ludicrously loud.

But the biggest dampener on the take-up of motorcycles is safety. Casualties have fallen over the last decade but riders are still 34 times more likely to be killed or seriously injured in a crash in Victoria than the occupants of a car.

Between 2004 and 2008, riders accounted for 13% of all road fatalities in Victoria despite motorcycles making up only 3% of total registered vehicles and less than 1% of traffic volume.

Problems like excessive noise can be addressed by better regulation and enforcement, as well as by improvements in technology e.g. electrically powered bikes. However, making motorcycling safe enough to attract large numbers of riders is a bigger challenge.

Fortunately, it’s likely that the population of prospective riders who’d benefit the most from switching to motorcycling is on average less vulnerable than existing riders. Those “waiting in the wings” are more likely to be risk-averse; to eschew large high-powered bikes; to travel and accelerate cautiously; and to see motorcycling as a utilitarian rather than recreational mode.

That measured approach should help to reduce all crashes, especially in the largest category: “out of control” crashes where no other vehicle is involved. The behaviour of drivers will still be a risk though, as it is for cyclists.

The author of this report, Stop the blame game, argues that in the great majority of accidents involving a motorcycle and another vehicle, the driver is to blame. It’s also likely that some “out of control” crashes are the result of riders “compensating for the behaviour of other road users (such as sudden lane changes by motor vehicles)”.

The number and speed of cars will need to be reduced significantly in congested urban areas if motorcycling is to attract large numbers of travellers and capitalise on its potential as a major urban travel mode.

However, it will be harder to segregate motorcycles from other motorised traffic than is the case with bicycles; motorcycles are faster and can travel at the same speed as other vehicles so they’ll need to continue to share road space with cars, trucks and buses.

It’s therefore likely the restrictions on driving necessary to make motorcycling an attractive option will need to be very strong. Fortunately, motorcycles are a good substitute for cars for many — perhaps even the majority — of urban trips in conditions where the private and social costs of cars are very high.

The great majority of streets in inner-city Australia could look like the Hanoi of 15-20 years ago before cars got such a foothold. The mode share of public transport and cycling still needs to grow but my feeling is there are many otherwise committed drivers who would find motorcycling an attractive option if the danger were reduced significantly.

It will require a long-term vision and considerable political courage to stare down opposition from rusted-on motorists, but provided they’re perceived as safe, I think motorcycles offer one of the most realistic alternatives to driving in congested urban areas.

They’re not the whole answer (e.g. there are other policies like congestion charging that must be part of the mix) but they could be an important part of it.