By Brendan Moyle 24/07/2019

I am back on the bicycle. The accident and ensuing recovery time, (and some work in China) postponed a return. Nonetheless, I’m undeterred. It’s good to be back on the saddle.

The Social Cost of Accidents

One of the reasons we give for why motor vehicles produce economic inefficiencies, is their social cost. Some of this is easy to understand. The congestion on motorways ends up being a type of cost that is imposed on other drivers (who reciprocate this- everyone loses). Without congestion fees or other similar economic incentives, we end up with too many cars on the roads. Another is the emissions from the tail-pipe. This produces local pollutants (microscopic particulates, carbon monoxide etc) as well as global (greenhouse gases).

Another social cost is accidents. If someone causes an accident on a road or motorway, they rarely pay the full cost of this. Other than the injuries and fatalities that underpin our value of statistical lives (around the $NZ5m mark per life), it generates other external costs. Everyone else is forced to slow down or halt. Roads are blocked. People can’t get to work or school or to meetings on time. All these people experience costs too- the cause of these costs does not have to pay for them.

The social cost of accidents was brought home for me too. I didn’t get the details of the motorist that caused my crash. So I ended up having to pay for a lot of replacement gear. That included a new (sort of) bicycle, definitely a new helmet (you can’t use one that’s been cracked in an accident), some new lights, and, well, because I don’t want to do this again, an action camera for the handle bars. That’s on top of losing a week of work while I recovered from a concussion.

The New Bike

The new bicycle isn’t technically a new bicycle. It’s an old one I found on TradeMe. It had been sitting unused in a garage for about 10 years. One of the reasons I like to get gear that is second-hand rather than new, is to reduce the environmental cost of my consumption. Reusing gear that’s already been produced, uses less resources than making something completely new. Even if we accept a bicycle doesn’t have quite the same manufacturing footprint of a car.

That also means taking very good care of what I do own so replacements are infrequent. So one of my first tasks was to give the bicycle a good clean. 10 years of old grease on the chain and cassette were not optimal.

The Cassette- before

The Cassette – Getting Cleaner

This is quite good therapy for when you are recovering from a concussion.

One of the reasons for keeping a chain and cassette clean is to improve the life of both. Tiny grit, mixed with old lubricants and oils, work away at the pins of the chain and grind away at the teeth of the chain rings and cassette. It’s also makes the bicycle more efficient, and quieter.


So I’ve added a short video clip of part of my commute with the new bicycle. One reason is to show how fast, even in a relaxed commuting riding-style, a modern road bike can move. Also, this is a really nice way to travel instead of a car…



There’s a lot of good reasons to use bicycles for commuting. The environmental reasons are pretty compelling. Many of the social costs we attribute to cars (congestion, tail-pipe emissions etc) shrink dramatically also. It is in this sense, more efficient. And compared to cars, the running costs are tiny.

Despite all the very good reasons above, there is one very compelling reason why I bike. It’s fun. It really is. Being outside, feeling the sun or the wind or rain on your skin. Stretching limbs that have been resting too long in an office chair. It feels good. This is not a unique experience to me.  Recent research has shown, cyclists tend to be much happier commuters.

0 Responses to “Back on the bicycle”

  • Great to see you’re back on the road.

    Off topic and on a rather sad note the Borneo Post has a story reporting the seizure a shipment of ivory and pangolins scales in Singapore. Apparently there’s about 300 elephant’s worth of ivory involved. (I’d give a link but Press Reader for some reason isn’t providing me with an URL for the article; maybe this will work in the meantime:

    • Hi Grant- thanks, it does feel good to be biking. I am a little more nervous about cars suddenly coming out at me still. The Singapore Strait Times reported the seizure yesterday too. It’s interesting I guess, that the bad guys are diversifying into pangolins as well as ivory. The closure of the Chinese domestic ivory market does not seem to have had the effect predicted…

  • Good to see you back on the horse! I’m a dedicated user of other people’s loss of devotion – bikes, snow sport gear, stereo equipment to name a few all have horrific depreciation in the first year which, coincidentally, is about how long it takes for a neophyte to find out they don’t really like the equipment and to flick it on.

    Recycling has direct financial benefits in my experience. Re-cycling has physical benefits!

    • Indeed. I’ve picked up some lovely photographic gear at times from people who have found their first rush of enthusiasm couldn’t be maintained. I do like my bike helmets brand new however…

  • Yes .. I had a tumble off my ebike a couple of days ago and cracked my head hard on some railings. Thank goodness for helmets; I’ve no doubt that mine saved me from a much worse outcome. Even though the helmet has no visible damage I’m going to get a new one. I must say that I don’t understand those who lobby for the right to not wear bike helmets.

  • At the risk of igniting the war: the argument against is at a societal level not an individual one. If you will ride anyway then requiring you to wear a helmet (and use lights in the daytime, ride only in bike lanes, travel only in off-peak hours etc etc) makes you safer. But if requiring helmets cuts the number of cyclists there is a threshold at which the net death rate starts rising again (and ditto for any other measure of safety or health). Many arguments come down to whether that threshold is met by the current law (including arguments that the threshold is at one extreme or the other).

  • I think helmets are optimal when you are traveling at speed, and you are mixing your ride up with cars. There are some circumstances where compulsion makes less sense. There used to be a long steep hill I had to cycle up on my route to work. So first up, I was never going at any decent speed. It also quiet and wide, with a generous margin on the left hand side. I wasn’t mixing the segment up with cars. I will concede I wasn’t always completely compliant with the helmet laws here. In fact, in summer it was nicer to have the head bare, reach the top of the hill, then fasten the helmet when I rejoined the traffic.

    If I’m going to be mixing things up with cars, I like a good helmet (and preferably one that has extra protection against concussions- live MIPS or Wavecel). But I believe at the aggregate levels there are some issues with helmets. One is that there is some evidence that motorists will pass closer to a cyclist with a helmet, and give those without a wider berth. The other as alluded to above, is if compulsory helmet laws discourage the adoption rate of cycling. Then you have potential more deaths via sedentary lifestyles, or tailpipe emissions from vehicles.

  • I think it’s completely possible to sustain a nasty head injury at low speeds. My tumble last week was at very low speed, but my head still hit the railings hard enough that I was super thankful of my helmet. I’ve bought a new Giro helmet with MIPS.

    I do understand the societal-level argument, but is there really evidence that compulsory helmet laws reduce participation in cycling? I think we need to be wary about applying overseas findings to NZ as a few things are different here. One is that the whole set up on NZ roads is much more hostile to cyclists, particularly in Wellington where I live. The short commute between home and work for me involves very steep and narrow streets, parked car hazards and no cycle lanes. The other is the nature of the social contract with ACC – in return for heavily subsidized injury treatment and rehabilitation we are required to take all practical steps to reduce risks.

  • Carol, when Aotearoa brought in mandatory helmet laws the number of cyclists almost halved. The eveidence from both countries that have mandatory helmets laws is unequivocal, the only objections are normally quibbles about whether “about half” is accurate or whether we should instead say “approximately a 48.5% reduction year-on-year, +- 0.25%”.

    Here’s a summary page with a lot of references showing declines from 30% to 50%:

    The best graphs I can find are from an anti-helmet group because sadly even collecting figures from is tedious (as well as less reliable than we’d like since they’re people reporting what they think they did in the last year in very broad categories, rather than actual counts of cyclists on roads)

    Sadly the better counts are hard to get access to even though they’re done by volunteers: From having done other counts I know they’re very labour-intensive and long time series are very, very rare. So we are left with the census and that’s AFAIK what cycle-helmets use above.

  • Carol, some of the only evidence in the world comes from New Zealand, because we’re one of the few places who’ve carried out the experiment. Pretty much everywhere else in the world either said “that’s a silly idea”, or later on said “wow, that really broke things in Australia and New Zealand, we should not do that here”. In Aotearoa the law roughly halves the number of cyclists, in Australia declines of 30%-60% were seen. summary of Australian research with references. has graphs for New Zealand. I have seen better ones but numbers are hard to find and the graphs harder.

    Halving the number of cyclists has serious effects and causes a lot of deaths and injuries. Directly to cyclists, because as much research has shown, the more cyclists there are the safer each cyclist is; and indirectly to people who don’t exercise or have to live with extra motor traffic and all the negative consequences that entails.

    (sorry if this comes up as a double post, my earlier reply with more stats seems to have vanished)

  • @MozofYarramulla It was just held up in moderation- WordPress gets suspicious when replies include links.

  • OK, thanks Moz. I’m totally prepared to change my mind based on evidence.