But appealing to the Majesty of the Law as standard to which all should be held, as though that were moral or fair, is a mistake, I think.

Traffic laws are typically designed around the advantages and limitations of cars. Stop signs get put up at intersections where there are a lot of car accidents, and traffic lights follow if car-based property damage or risk of injury continues. Traffic lights are timed so that car-sized vehicles travelling at car speeds can flow reasonably well together, while reducing the risk of property damage. Talk to a traffic engineer about their motivations for setting up particular intersections or light sequences, and see if they mention bicycles.

There is an “Idaho stop” law in some jurisdictions that allows bicycles to run stop signs if they can do so safely — this, along with bike lanes which specifically privilege bicycle traffic, is the start of formal (i.e. legal) recognition of the fact that bicycles operate differently in traffic than cars, and you can see the rage that even this simple step has generated.

I’m a recreational cyclist who lives in a major east-coast US city, and I have a pretty pragmatic approach to the rules of the road. It’s true that I can generally get away with blowing through stop signs and anticipating the occasional green light, but it’s also true that the rules don’t protect me as much as they do cars, because the laws are mostly about property damage (seriously, one measure of the seriousness of an accident is the dollar value of the property damage), and bicycles have low monetary value compared to cars. If someone backs out of their driveway into me, or turns right across my path, and I get hit, the police, whatever their personal sympathies, are unlikely to take official action. Even if I’m injured, the stats affirm that, under the law, it will likely be treated no differently than if I had simply fallen off my bike, and the third party who violated my right of way may not even be mentioned in the report, if indeed a report is even filed. The equivalent car accident would involve greater property damage, insurance claims, and police reports with great care paid to names and addresses of those involved.

Which is to say, in cartoon form, if the rules of the road do not respect me, then I am less motivated to respect them.

For clarity, I reiterate my understanding of cyclists’ formal obligations under the law, and the common sensibility of behaving courteously and predictably in traffic.

But thanks to the internet, I now realize that the only option remaining to me is to run myself over while rolling through a stop sign so that my purity of essence is not lost! Thanks, internet!

The point is that it is ridiculous for cars and bikes to share the same laws. The “Idaho Stop” law, mentioned above, where a car stop sign is equivalent to a yield sign for bikes, is a good example of different laws for different realities.

That logic needs further extending when it comes to creating laws for bikes.

All I can say about that is, if your lives are so easy that this is all you’ve got to fight about, then that’s pretty amazing. We have hungry and homeless, unemployed, decent people all around my town. They sure could use a little help from you folks enjoying the easy life. I mean, if you can stop squabbling over bicycles and cars for a few minutes. Lord knows we here in reality would hate to interrupt such important business.

32psi will do you, folks.

If there’s one thing I’ve learned about those who beak about “entitlement”, they’re usually those the most oblivious to their own privileges and the most selfish when it comes to responding to any suggestions of sharing – as in the road.

FYI – I drive to work, and I carpool.

I’m no longer surprised when the same people who’d weep tears of blood because of stereotyping of other minorities are happy to accuse “Americans” of generally being assholes.

I’ve spent time in each of the cities you mentioned. So what?

Bicycle commuting isn’t a viable transportation option for a city. It’s a lifestyle choice, like sadomasochism or perhaps some sort of cult that ends in beverages sweetened with cyanide.

The city I call home – Vancouver – is currently spending millions of dollars tearing up downtown city streets to convert car lanes into bike lanes. The downtown grid used to be relatively well balanced: it’s now a nightmare. Everywhere I look, kilometers worth of nearly empty bike lanes, put there to enable an ideologically-driven lifestyle choice masquerading as a solution to global warming, foreign oil dependence, and the really sad cancers that little kids get.

None but a small minority want to get on their bikes (especially in a city with 166 rainy days per year) to get dirty and sweaty while getting to their destinations at a third the speed of a powered vehicle. Funny then that the latest fashion is to dedicate a third of the road grid to cycling.

1) Motorists exceed the speed limit for most of the distance they cover. The only thing that stops them breaking the speed limit all the time is other motorists getting in their way.

2) Most turns and lane changes are not signalled. I mean, with a Starbucks in one hand and their cell-phone in the other, how could they be expected to do this?

3) Motorists NEVER stop at stop signs unless their advance is directly impeded by other motorists. I mean NEVER. Sure, most slow down to about the speed of a bicycle, but stop? NEVER. You can confirm this by observation.

Yes we expect to be able to use the road as we have the legal right to, and not be driven off the road by raging d-bags like yourself. Oh and many of us drive cars sometimes as well….imagine that.

I have a device you just don’t see much anymore: a tire pump that screws into a spark plug hole on your (pre-OBDII) engine, and it slowly inflates your tire via engine compression. God only knows what the atomized fuel will do inside your tire, but dating from an era when air compressors were pretty few and far between outside of service stations, it did the job. My dad used it for years before I was born. I used it successfully once, back in the late 80s. About ten years ago, the hose had degraded enough that I kept the valves and fittings and junked the hose, with an eye to replacing the hose sometime later. Still haven’t gotten around to it.

It’s a neat piece of midcentury toolbox.

You should see how drivers rage when stuck behind an old granny driving exactly at the speed limit.

Oh, speeding on the highway isn’t as important as a bike running a stop sign? Oh wait, it’s just one of the leading causes of death in the US.

So how about a deal, car drivers: if you’ve never once driven over the speed limit, then feel free to get angry at others breaking road laws. If not, shut up.

I ride both a bike and a Vespa (and a car when need be, but don’t own one). On both I see cars breaking the law all the time, but the other biggest one, besides the speed limit, I see all the time on the Vespa: Cars really really really really suck at using their turning signals. They really don’t use them. They are so incredibly bad at signaling their turn. On my 50-minute commute to work outside of Boston I count off the idiots who don’t signal — I normally reach 30-40 just on my way in.

(Ohhh, and this “pump” displays a failure of understanding physics, as others have said.)

Could you kindly explain the physics involved when you connect this between a flat bike tire at 0 psi and a car tire at 30 psi, and the air is pumped into the bike tire?

Think about that.

But it makes sense – It’s ideal gas law. Pressure * Volume = Ideal Gas constant * number of particles * Temperature. All the car is going to do pressing down on the rim when mounted is change the volume, and the pressure will rise proportionally. If the tire is fully inflated, it’s not supposed to deform when on the car (ideally, although it does just a little bit), meaning no volume change, meaning no pressure change. Sure if you have a whole in the tire, the car pressing down on it will “sqeeze” the air out of the tire, and the volume will change, but really the weight of just the rim can do that too.

At the end of the day, the pressure is going to equilibrate and that’s it, 30-50psi still represents that maximum you can get out of the car tire, the only thing the effect of the weight of the car will do will be to effectively increase the volume which will come out before the pressure drops in the car tire.

Really, I have a pocket pump that will do even 50 psi in less time that it would take to sponge off a car.

The best use I can see for this device – ironically enough, is for motorists. Like jumper cables for tires. Sure then you both need to find a service station, assumingly your 40 psi tire, if completely flat, will be now at 20 psi and so will your helper, but you can drive on that. It would save changing a tire and all you’d need to recover from a flat would be this and one of those little $10 “tar snake” tire repair kits. (or better yet you can just inflate the flat with one of your other tires).

I imagine the cyclist would get a really mean look as your friend decided he better take a long lunch before getting started, then he’d have to gather up a few more fellow workers to sit around and watch the eventual beatdown. Of course by then this person would be long gone……

As always, there are other factors to consider. Temperature effects (adiabatic expansion of the air will cool it) may alter the result and, strictly speaking should be taken into account. I think allowing the temperature to revert to ambient after the transfer is complete eliminates this effect, though. The other factor is the elasticity of the tyres themselves as the volume will slightly change in response to the pressure changes. I think this can be effectively disregarded for tyres as the effect will be small, but it means that trying to model this with balloons, for example, would be fraught. Having said that, the car will squash the tyre down a little as it loses air and this volume change might be more significant. You would get a slightly different (lower) outcome if you stole air from the spare.

The bottom line is that the maximum pressure is less than 30 psi. This is inadequate for skinny-tyred bikes (close to unrideable) but is fine for a mountain bike.

I started biking to work this spring. My 7.5-mile commute on a bike takes 40 minutes. Same commute via public transportation: 60-75 minutes. Same commute via car: 25-30 minutes (outside of rush hour).

I live in Boston. 2/3 of my commute is on a nice protected bike path along the Charles River. It’s gorgeous. I get to work feeling cheerful and invigorated, instead of cranky and impatient. I’m saving money. I’m in decent shape now, and I’m a 38-year-old geek who’s never played a sport.

Sounds viable to me! I think there are some cities in Europe that’ll disprove your thesis non-anecdotally, but then Europeans are tougher than Canadians. Apparently.

If all the bike lanes are empty then obviously it’s a pretty viable method for getting to work if you’re on a bicycle.

And comparing speeds is a bit of a red herring. A third of the speed, and a lot less then a third of a tenth of the price – don’t leave that part out. As for sweat – it’s healthy and enough people don’t mind. You can pretend that because so many more people drive there just isn’t the populist support for the bike lanes, but in practice that’s obviously not true seeing as how people seem to keep voting in favour of these measures.

And another thing – there are plenty of cities without any bike lanes to speak of that still have massive traffic jam problems. So how come that makes bikes unfeasible instead of making cars unfeasible?