Could powered two-wheelers be a game-changer for urban travel?

Five: weather will limit the appeal of two-wheelers for some travellers, but the high proportion of Europeans who cycle in harsher conditions than Australia experiences show that this is not necessarily a deal-breaker. Travellers will take to powered two-wheelers if they see them as safe and if they out-compete other modes on travel time and cost.

Mode share

What sort of mode share could a network of powered two-wheelers win?

Cycling in central Amsterdam has a claimed mode share of 40%. That seems an unlikely goal in Australia, but even if two-wheelers accounted for just 5% of all motorised passenger travel (km) in Melbourne today, that'd be much larger than the 1.3% mode share of trams, or the 2.4% mode share of buses. If two-wheelers won 10%, they'd handsomely exceed the current 6.7% mode share of trains (although still a far cry from the current 89% mode share of private vehicles).

Measuring mode share by the number of trips rather than km of travel doesn't change the overall calculation by much. According to VISTA, the share of motorised trips on a Melbourne weekday taken by tram and bus is 2.1% each. The mode share for train is 6.2% (88.5% for car).

Because two-wheelers offer many of the benefits of driving, they could draw significant numbers of travellers away from cars.

Infrastructure

Is the required infrastructure affordable?

It would be costly to build a largely segregated network for two-wheelers. However, their light weight and small size suggests the per km cost could be an order of magnitude lower than that required for new motorway and track-based infrastructure.

Expenditure in the order of $10 billion could establish the foundation for a safe metropolitan-wide two-wheeler network. I assume extensive traffic calming and intersection works, selected grade separations, and a number of entirely new roadways for two-wheelers. I also exclude existing shared trails; leave them for walkers!

That's a lot of money but it's not so daunting when we consider that the Victorian government is committed to building the $16 billion North-West link motorway, $11 billion Melbourne Metro tunnel, $10 billion airport rail link, and the promised $50 billion suburban rail loop. Note also that the cost to build Melbourne's 250 km tram system today would be around $35 billion, assuming an average $120 million per km, plus $5 billion for vehicles and supporting facilities.

Politics

The biggest problem would be political, particularly taking (some) road space away from cars. The key thing here, though, is that powered two-wheelers are a reasonably attractive substitute for cars because they also provide on-demand, point-to-point, private travel. Given sensible policy settings for cars, they would also offer faster trips in congested conditions, cost travellers less to own and operate, and be easier to park at home and at many destinations.

City managers could choose to make two-wheelers irresistible for many travellers, even in Australia's big cities.