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Comment Re:Wheels, and price (Score 1) 85

Click through, read the link. They've done experiments with counter-rotating wheels to cancel any gyro effects, and people ride the bikes just fine. So, negligible. As good as nothing, compared to all the other noise in the system.

And if you have ever captained a tandem, you'll know damn well it is all about "noise in the system".

Comment Wheels, and price (Score 2) 85

There's way too many people who think that big wheels have a stabilizing effect. They don't. See http://en.wikipedia.org/wiki/B... .
They do suck more at potholes, but they are also much stronger (as wheels) though the load carrying capacity of the tire is reduced (i.e, a 29x2.35 *tire* can carry more weight than a 20x2.35 tire).

$850 would be an aggressive price for a small run bike. I know what I am talking about here, I own a small run bike (a cargo bike), it's larger, but the frame alone was $1000 retail, and they're pretty much all like that. Most niche market bikes cost more than $1000, and while this one has not so much tubing, it has just as many welds, and it pays the tandem tax (more drive train, second seat, and lots of parts are extra beefy for the increased power and load -- I also own a tandem.)

I share the concerns about the fork angle, but you'd really want to ride one to figure out if it works or not.

The stoker not able to see the road is a problem for some stokers, so I think this is an interesting thing. I wouldn't buy it without riding it first.

Comment Re:Yes, smaller wheels are tougher, (Score 1) 85

Bike balance hasn't got diddly to do with angular momentum of the wheels.

"On the other hand, if the gyroscopic effect of rotating bike wheels is cancelled by adding counter-rotating wheels, it is still easy to balance while riding."
http://en.wikipedia.org/wiki/B...
(And they got it from _Bicycling Science_, which is where I remember it from.)

Comment Re:I imagine it will stay (Score 1) 267

I think driverless cars are going to travel more slowly near pedestrians, though they will also take advantage of knowing exactly where they can swerve in a pinch and that will reduce their constraints somewhat. Humans take stupid chances because they think they're better drivers than they really are; deep pockets will be responsible in the case of the driverless cars, and they'll be accordingly more careful.

You also have to consider the possibility that some pedestrians may be quite aggressive; certainly, if a driverless car tries to push its luck at a crosswalk, sooner or later it's going to get a shopping cart shoved into its grill, or get the studded tires of an (ahem) icebike rammed into its side. I know dads of kids at the local elementary school who would throw snowballs at the windshields of cars that didn't stop at the school crosswalk (no crossing guard, the police said it was "too dangerous").

Comment Re:I imagine it will stay (Score 1) 267

The car does have brakes, and "at speed" is not that large if you're a conscientious driver in a place that's already got pedestrians in it. If people are tailgating you, then you driver slower yet, so as to reduce the stopping distance that they'll need or increase your ability to stop both cars quickly. And yes, I know that you can get rear-ended stopping for pedestrians, it has happened to me, and I saw it happen to someone once who stopped for me (at a crosswalk, thank you very much). The law (at least in Massachusetts) is pretty plain; you have an obligation to not hit the pedestrian. You do not have any obligation to yield to the non-emergency vehicle behind you. Arguably, honking your horn to indicate "I intend to break the law" is also a safety issue.

The issue is also one of self-training -- if you train yourself to always hit the brakes instead of preferring the horn, then when you come across the pedestrian who doesn't hear, is too young, or mentally not all there, you'll still stop fast.

Comment Re:I imagine it will stay (Score 1) 267

A conscientious driver would use the brakes instead; they work better. Honking a horn depends on the person who needs to hear it, hearing it, figuring out that it applies to them, figuring out the appropriate response, and responding. They could be deaf. They could be distracted. They could be mentally disabled in some way (we have friends with an autistic son, he went walkabout one fine morning, quite the panic, till he turned up two miles away). Or, you can just step on the brake, stop the car, and wait for the problem to clear more sedately.

And yeah, you might be delayed a few seconds. I think that's less important than not hurting people.

Comment Re:Most (Score 1) 249

"Discrete mathematics" -- I don't think that word means what you think it means.
(I know a whole lot more about discrete mathematics than I do about statistics or climatology.
Look it up on wikipedia, see if you see very much at all about sampling theory or statistics.
Yes, they DO mention discrete probability, but it is a tiny corner of the whole.)

Comment Re:IPCC AGW predictions FAILED (Score 2) 249

Don't know if you've ever compared the three amounts of energy, (1) solar energy incident on the earth in a year, (2) heat of fusion of the Greenland and Antarctic ice caps (i.e., energy to melt them, assuming they are at 0C and frozen) and (3) the amount of energy required to heat the oceans by 1 degree C. The ratios are roughly 1 : 1.8 : 0.9. (My arithmetic: http://dr2chase.wordpress.com/2012/02/04/numbers-that-were-larger-than-i-had-imagined/ )

For me, this was simultaneously stupefying, scary, and annoying. Scary because the thermal mass of the ocean is incomprehensibly large, which means that burps and blips in the South Pacific can overwhelm any minor atmospheric effects, and annoying because in any discussion with internet "experts", no matter how correct it might be to blame the ocean, neener-neener-Al-Gore-said-it-would-be-hot-by-now.

Comment Re:Protecting pedestrians from bad drivers (Score 2) 136

For either sense of the word "blind", if there's a pedestrian and it's a crosswalk, the law says you're supposed to stop for them. They are not supposed to stop for you; they have right of way. If visibility is not so good, that is presumably because the highway department assumed that you, an allegedly safe driver, would reduce your speed correspondingly so that you could always see the pedestrian that you are legally required to stop for. If you are ever honking at a pedestrian in a crosswalk, or a blind pedestrian crossing a street anywhere, either your brakes have failed and you are warning them of this unusual hazard, or else you are doing it wrong.

If someone's approaching a stop sign at a high rate and it doesn't look like they are going to stop, the safe thing to do is brake ahead of time. For honking at them to work properly, many things have to happen in a timely fashion -- they have to hear you (dead people can be licensed), they have to figure out you are honking at them, they have to figure out *why* you are honking at them (presumably, if they saw the stop sign, they would stop for it, right?), and they have to react. Ideally, if the reason they were not stopping was that their brakes had failed, they would already be honking their horn.

The overwhelming use I observe for horn use is "the light is green and you're not moving". That is not a safety issue -- cars not moving is in fact quite safe, albeit frustrating.

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