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Comment by unglaublich | Hacker News Reader

Some motorists seem to forget that cyclists don't need a 30m wide, 40cm thick, heavily reinforced highway with stabilized foundation that has to be revised every year to account for the damage caused by heavy vehicles.

The costs of a cycling path that support the same flow of people is negligible compared to that of a corresponding highway.

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No one ever says "why don't we charge pedestrians fees for sidewalks," for good reason. Bike infrastructure should be thought of as the same way. A paved bike path is going to be like a sidewalk: it will last as long as the elements permit it no matter the amount of usage it sees. Versus a road used for vehicular traffic that is heavy enough to degrade the road, that sort of usage makes a lot more sense to tax.

That isn't true. Pedestrians put more pressure on the ground than cars do. Google it if you don't believe me.

The reason sidewalks last so long is they're made of cement rather than asphalt. If you made roads out of cement they would last just as long if not longer.

And the reason they make sidewalls out of cement is they have to. If they made then out of asphalt they would decay very quickly.

Have you ever seen an asphalt bike lane age? It never gets potholes. The top layer just expands and contracts or is invaded with tree roots. Over time the elements wear out the tar and the gravel loosens.

Compare that to a road where the truck literally forms grooves into the asphalt. It ripples like the viscous material it is in those conditions under multiple tons of weight. An intersection by me looks like its plaid with the grooves from perpendicular trucking traffic. And cement roads do last a long time but they aren't indestructible. I live on one. Trucks damage them and crack them up over time and the city has to fill in potholes. The more construction going on the more damage. Any big apartment build just destroys the concrete apron and sidewalk on the lot with the equipment because its that heavy. Orders of magnitude heavier than any human on a bike can be.

Only if they are all wearing high heels... It isn't pressure that typically causes damage though, it is shear stress or frictional power.

"Google it if you don't believe me."

Or, just calculate it?

Car contact patch is 4 x 160cm2. https://www.tirerack.com/tires/tiretech/techpage.jsp?techid=... Car avg. weight is 1800kg. https://www.bankrate.com/insurance/car/average-car-weight/

Pressure = 28kPa

Human is 100cm2. https://en.wikipedia.org/wiki/Pedobarography Average human weight is 75 kg.

Pressure = 8.5kPa.

So it's simply not true what you say.

People don't normally walk barefoot.

Run the numbers for high heels, and keep in mind they might put their entire weight on the heel.

The thick, heavily reinforced roads with stabilized foundations generally have much nicer surfaces to cycle on than narrow cycle paths though, at least around here. Probably because a lot of the deterioration is caused by weather rather than traffic and the cost reduction is mostly through having lower standards and accepting more deterioration.

I'd take a rough separated cycle path over a shared car road any day.

Depending on what type of bike you have. On a mountain bike, anyday. On a road bike with paper thin tyres that easily puncture, maybe not so much.

Usually the concern is getting hit by car traffic.

At least in the US, drivers don’t drive well around cyclists, and sometimes that’s intentional to boot. Better to not share the road with people who are actively trying to hurt you with a metal object weighing several thousand pounds.

Road bikes aren't really designed for being in traffic in the first place so that places some of the downsides of that on the user. I've used one for many years, so don't get me wrong, I love riding one but it is abundantly clear to me that when my bike tires fits into the slots of a drain that that is my problem and not the problem of whoever designs and maintains the road.

In many places a road bike isn't actually street legal (no bell, no fenders, no lights, of course you could add those).

It sounds peculiar that some places would have requirements for bells and fenders in order for a bike to be "street legal"; this strikes me as more of a quaint historical holdover than anything else. Some cyclists might be more comfortable with ringing their bell a than raising their voice if they need to urgently signal the attention of another road user, but a requirement for a bell on any bike is mystifying to me. Likewise fenders; cycling on wet roads can cause dirty water to be sprayed onto a vehicle that is driving close behind a cyclist, but people don't tend to cycle on road bikes in wet weather in the first place (unless their bike has been adapted), and people should maintain a safe stopping distance, especially in wet conditions. But the use of lights when cycling at night is a perfectly reasonable legal requirement (more or less universal in my experience), and perfectly effective temporary lights can be easily attached to road bikes if necessary.

Definitely concur, for commuting I ride a pretty wide tire for that reason. I've actually really enjoyed cross-bikes for city commuting, since they're designed for a bit more of a pliable ride and more comfort while still running pretty fast overall.

Just put some good tires on your road bike and you wont deal with flats. I have used gatorskins which have always been indestructable, tubes last for years and are only replaced when I put new tires on the bike. I'm moving to the continental gp5k for the next set because apparently the puncture resistance is good enough these days in those more standard road bike tires. Unless you manage to hit an upright nail you shouldn't worry too much.

Bikes are a lot less delicate than people seem to think. My daily driver has road bike rims and tires. They're quite durable. The region has some bike paths that are crushed limestone on hard clay, and sometimes I find myself on gravel roads, off-road shortcuts, or even "easy" mountain bike trails.

The main issue is comfort. Riding rough roads on hard tires gets old after a while. Also, real MTB'ing, where the trails are designed to be challenging, is its own beast.

I also prefer avoiding car traffic if possible.

It's me that is not durable, if I had to ride daily on 80psi road tires I'd shake to bits!

Funnily enough I do MTB, and I have a full suspension and a fully rigid frame both offering their own challenges.

No they don't, cyclists prefer concrete bike paths which both last longer and have a smoother surface.

> The costs of a cycling path that support the same flow of people is negligible compared to that of a corresponding highway.

That's not true The ground pressure of a bicycle is higher than the ground pressure of a car.

Some bike tire pressures exceed 100 psi. Only the largest trucks have ground pressures that high. A typical passenger vehicle has a pressure of around 36 psi.

The ground pressure of someone in heels is even higher than that. There's a reason sidewalks are made of cement while roads can be made of cheaper asphalt.

Ground pressure is not the only way a road wears.

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