We have alot of concrete freeways here around San Diego. Actually they are all slick when it rains because of the road grime build-up. We don't get much rain, so when it does it's just one huge "Slip-n-Slide". Plus there are also the uneven rain grooves. Even when it's dry the bike can get a little squirrelly sometimes. The joints are just another nuisance to deal with.
To answer your question; Yes, it is slippery stuff, especially when wet. Riding on concrete and having these little bits of heaven roll under your tires can lead to some very interesting moments. It can get real exciting when leaned over.
The tar like product that has rock chips rolled into it and is then rolled down is called "chip seal" in the Phoenix area. Probably has a bunch of names depending on where you're from.
The tar strips you see on the roads and highways in the USA are often called "road snakes". Again, depends on where you're from.
IMHO, tram lines, railroad tracks to us Yanks, are the most common road hazards I can think of. Even worse when the approach is a steel plate!
my mom works for an asphalt company so i know a bit about this stuff.
the "road snakes" are usually something called "asphalt cement", at least that's what it's called on the east coast. it is petroleum product that is applied hot and then hardens as it cools but is designed to stay a little soft so it can flex and seal joints in asphalt like cracks or the edge of a repaired spot.
here's how they fix cracks in asphalt. a good job entails cutting the crack open to a uniform width, clearing it of debris and then laying in the hot asphalt cement (hot AC) to a level just over the road surface. it bonds to the sides of the newly cut channel and the top road surface. it seals the road surface together keeping water from getting under the asphalt and ruining the road. often, there is no cutting of the asphalt and the hot AC is just laid on top of the crack. this does not adhere as well but is a faster and less expensive procedure. both procedures are much less expensive than a full repaving.
when cool it is pliable, you could dig a screwdriver into it without much trouble. when hot, like under hot summer sun, it is almost liquid again. it can get stuck to your shoes and tires and may pull away like chewing gum.
no matter what temperature this stuff is much slicker and softer than regular asphalt. i once saw a guy lose his front wheel on a full dress harley and wash out on a hot summer day. it was at a traffic light. he was only going about 20 mph and in a very slight curve. scared the hell out of me to watch him go down that easily. he limped away, stiff but not too hurt.
I'm wondering if Metzeler named one of their touring tires "Macadam" from tarmacadam you mentioned.
Anyway, as far as road hazards go, I'm surprised some of the other Californians haven't mentioned the Botts Dots - or as I like to call them, Satan's Death Bumps.
I've bitched to no end on previous threads on these ridiculous contraptions. They are essentially "rumblestrips" for lanes. And as far as I can tell, only the backasswards state has them.
They are 1.5" to 2" high reflective plastic "bumps" spaced a foot or so apart all the way down the lane on the paint stripes. I suppose Cali government doesn't think simple lanes stripes are enough - like everywhere else in the Free World. No, we have to deal with these Godforsaken things on ALL roadways. I'm sure they've killed more than a few motorcyclists. They kick and shimmy your front wheel when changing lanes (unless you can cut real sharply from one lane to another and try to split between them). In the dry, they're highly annoying and if you're leaned over (like making a left turn onto another street), I've had my front wheel skid out, then grab and jerk the bars violently more than a few times. In the wet, Faaaaahgettaboutit! Pucker up your rear and pray.
The designer of them (perhaps someone named "Botts"???), the flathead screwdriver, and Allen head bolts should be strung up and made to die a slow and torturous death (ever see the "vice" scene in the movie "Casino"?, that would be good).
I'm going to miss fantastic mountain roads here, but at least in less than 2 weeks, I'll hopefully never have to deal with these damned things again! :yell: :yell:
Small correction (meant in the nicest possible way) jajamase ...
Tramlines are tramlines, railroad tracks are railroad tracks.
I was staggered to hear recently that my fair city (Melbourne, Australia) is one of only five in the world to have a tramway (ie. streetcar) system.
I think this may be playing with words (ie. I don't believe it), since surely lots of cities (eg. in Europe) have so-called 'light rail' systems, which are not too different (albeit perhaps they travel a little faster).
Anyway, tramlines run along the road, meaning that for miles and miles you have two potentially very very slippery strips going in the same direction as you. Particularly nasty when it's wet.
We learn to avoid them (or cross them at a distinct angle) very early in our riding careers.