If they’re tempted, other Australian cities should think long and hard before committing to bike share. If private investors are prepared to take on the risk that’s fine, but it’s highly unlikely they’re interested. The fact is bike share will only happen if taxpayers stump up the funds.

Cities should ask themselves, first, if bike share warrants funding and, second, if there might in any case be better uses for the money. There are several issues they should consider.

The obvious number one concern is the mandatory helmet law. It’s universally cited as the reason why Brisbanites and Melburnians haven’t embraced bike share with anything like the enthusiasm of Parisians and Londoners. However there are possible solutions to the helmet issue.

Those who oppose the helmet law argue that users don’t want to wear a helmet, but I suspect they’re well and truly out-numbered by those who don’t use bike share simply because they can’t get access to a helmet easily. Providing cheap helmets at point-of-sale — for example for $2 via vending machines — might address most of that problem.

But that’s not the only concern. Even if the helmet issue is resolved, it doesn’t necessarily follow that residents of cities such as Perth, Adelaide, Sydney and Newcastle would enthusiastically embrace bike share. As I’ve argued before, there are other factors, particularly fear of cycling in traffic, that might retard use of share bikes.

Safety is a much harder issue to address in the short-term than helmets. Unfortunately, our cities don’t have the bicycle infrastructure or the positive cultural and legal disposition towards cycling of many European cities.

The scale of financing could also be an obstacle to any city contemplating bike share. Melbourne’s scheme was set up on the basis it would cost $5.5 million over four years, but I expect that must’ve at least doubled by now. One reason for its lacklustre performance could be it was done on the cheap.

There are just 600 bikes and 50 docking stations in Melbourne, compared to 20,000 bikes and 1450 stations in Paris’ conspicuously successful scheme. So the cost and risk for government in a city such as Sydney could be considerable (the Paris system cost a whopping $140 million to set up).

Apart from these practical constraints, other cities might also ponder what benefits bike share would deliver to justify the subsidy. This is not a question that bothered Melbourne or Brisbane, to their cost. Their key motivation was “greenwashing”.

They set up bike share to sell an image of sustainability, never mind the substance. Either they were ignored, or nobody did the sums that would’ve led to the obvious but inconvenient conclusion — “it won’t work until the helmet issue is resolved”. As it’s turned out, bike share has probably done damage to the image of cycling and sustainability in these two cities.

Even if Novocastrians were confident ridership would be much higher in their city than in Brisbane, hard and probing questions should still be asked about the benefits of bike share. The key pay-offs usually cited are greater mobility and increased sustainability.

The mobility benefits seem obvious. There are plenty of trips within the city centre and inner city of Australian cities that would be faster and more convenient by bike than by public transport. After all, bikes are a form of individual transport not dissimilar in some respects to cars. They’re available on demand (no waiting), go direct to the destination (no transfers), and, notwithstanding the term “bike share”, don’t have to be shared with strangers during trips (no stops).

Still, while it’s far from perfect, public transport in the centre of Australian cities is pretty good and is getting better. The centre is where all the radial train, bus and tram lines converge. Cities should ask themselves if public subsidies should go to a competitor mode, or whether they would be better spent on improving inner city public transport.

Cities should also ask if bike share would deliver a significantly greener outcome. Unfortunately there’s an absence of hard data on this question, but improvement in sustainability will only be marginal if, as I suspect, share bikes mainly substitute for walking and public transport trips, or induce trips that wouldn’t otherwise be made.

Read the full story at Alan Davies’ blog, The Urbanist