Well, I've never heard that before.

Studded tires on cars are illegal in the US. Apparently reducing wear on the road surface is more important than reducing accidents. They're probably illegal on bikes too but I don't really care.

With the exception of Wisconsin and Puerto Rico and with some seasonal restrictions, they are allowed in the other 49 states, according to AAA

+1, in most states, studded tires are legal during the winter months, though in some, are illegal otherwise, ie. April - Oct, or something.

Many only with rubber studs. What the heck is a rubber stud? Google isn't helping me.

It's a stud. Made of rubber. Really. They work nearly as well as carbide studs, and dont' damage the pavement. Also, modern studless snows work better than studs almost all the time. The remaining exception is icy surfaces (not snowy) when the temperature is right around freezing. Colder than about 20 F, studs don't bite ice any better than rubber, and really cold, rubber wins. That's cars and light trucks, bikes are different, because the pressures are so different.

snow tires in Puerto Rico. I wonder why they are illegal there?

In this house, we obey the laws of thermodynamics!

Having ridden studs on ice (and driven them in a car) on ice, I don't agree. The argument is that the studs are not as effective on dry pavement and that's an issue because you don't have ice 100% covering the surface.

Around here (Minnesota) it gets plenty cold and where I live, it's not unusual to have ice covered roads for weeks at a time. Studs (carbide) work great. Rubber does not.

J.

That's new one on me too. I hate studded car tires (almost as much as I hate studded bicycle tires), especially the ones that are being run in July in Colorado. We allow them all year long which tears the crap out of our roads.

Here in PA from what I remember studded tires are only allowed Nov-April. However, my biggest complaint is not the studs, its how much UNNEEDED LIGUID SALT is put on the roads! Not only does it ruin our roads (probably more than studs) but what it does to our vehicles, and the environment. I just put studded tires on my bike yesterday as I commute in the evenig and back into the wee hours of the morning. The rolling resistance is more but I will take it!

You can disagree all you want. The actual performance data, though, is clear. Top quality studless tires are better, except on ice, in a very narrow range of temperatures, centered on freezing. Twenty years ago, that wasn't true, but technology has improved.

The things that racers use on frozen lakes are different, with much longer spikes. They work, but destroy pavement.

Q. Anyone else have issues with black ice?
A. Studded tires.

Being an engineer, I get data. Being an engineer, I also get how data doesn't always match reality. I've ridden studded tires on ice from above freezing to near zero fahrenheit and there is little difference in how they grab (always good). I also live in a climate where we get major ice from November until April and where we get *real* black ice on the roads from car exhaust because it's too cold for salt or calcium chloride to work. If studded tires were allowed here, we'd all be using them on our cars as well as snowmobiles (for those of us that have then, I don't).

There is a difference if you have perfectly flat ice - think ice skating rink - but that isn't what icy roads or trails are like.

J.

right

This is why, during the winter, I only ride on paths that are physically segregated with something likely to stop a car that's sliding my way (curb, parked cars, ditch, etc). I just do not trust people driving 4000 pound cars to pay attention, let alone drive safely in the winter. I won't put my life in their hands.

And I put Marathon studded tyres on my bike to help protect me from me.