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» Hatrack River Forum » Active Forums » Books, Films, Food and Culture » Tour Tidbits [Sprinting explained in detail!] (Page 1)

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Author Topic: Tour Tidbits [Sprinting explained in detail!]
Hobbes
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Well in count down to le Tour de France I wanted to do a daily trivia thread. Each day until the first day of le Tour (July 3rd) I'll post some little trivia on either le Tour itself or cycling in general. I'm hoping this will give people motivation to watch, or at least pay attention to the Tour, and if they do, know more about what's going on. [Smile]

Today, we'll learn about how climbs are described. The climbs are rated 1,2,3,4 etc, where 4 would be easier than 3 (though you'll never find anything rated above 4 as it would simply be too trivial to bother with rating). There is also the HC, or hors categorie (often reffered to as 'Highest Category', but actually means 'out of category') climb, which comes before category 1.

There are a few things that go in to determining a category number: % grade (steepness, a 10% grade goes up 1 meter for every 10 meters it goes forward), length of climb, how far into the stage it is, and to a smaller extent, road condition. There is no hard and set mathematical formula for determining the category of a climb, but you can follow a few guidelines. 4-5% will be on the low end (probably about category 3, 4s are rated but normally overlooked by the riders since they are so easy). A climb has to go up 100 meters elevation to be categorizied, and teh HC climb will often go up well over 1000 meters. Typically any mountain you'll hear about the riders going up will be HC, that's where all the attacks come, where all the action happens. Occasionaly someone will try to win a cat 1 climb, but HC dominates the Tour.

[EDIT: Tour Tidbits just plain sounds cooler, even if I do mention non-tour specific things [Cool] ]

Hobbes [Smile]

[ July 01, 2004, 04:59 PM: Message edited by: Hobbes ]

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Hobbes
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By the way, everyone should feel free to ask questions, either about the day's trivia, or a completely unrelated cycling topic (like how to the riders go to the bathroom in the Tour?)

Hobbes [Smile]

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Polio
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How do riders go to bathroom in the Tour?
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Hobbes
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[Cool]

Throughout the day as necessary riders will fall back from the peleton (the big group of riders that stay together) and simply go off to the side of the road, then go and catch up to the main group. Often, earlier on in the race, one of the more senior members of the pelton (remember senior is a realitive word, the oldest man ever to win the tour was 37, and that was in 1922) will call for a break for the whole peleton.

Later on in the race if a racer really needs to go but things are heating up it can get more trickey. Typically, if the racer really needs to stay in the front group, they'll drop back a bit with a teamate, and the teamate will push them as much as they can while the racer goes to the bathroom while cycling, a rather tricky maneuver!

There's an unwritten code of conduct for this (as there is for a lot for cycling things) you do not attack when a race contender is responding to nature's call. There's also an unwritten rule with the media to not fil this in any way, which is why you never see it.

Hobbes [Smile]

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BannaOj
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<grin> while I knew the correct answer, I thought of trying to convince everyone that they have a specially adapted motorcycle that pulls a porta potty for this special purpose.

I do believe that in this high tech era the riders diets are adjusted for the maxiumum usable energy and minimal solid waste so that the need to poo en route is less than the possible peeing. As we all know poo is just a little more time consuming.

AJ

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Hobbes
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Riders typically eat special "energy gels" while riding, that are designed for the type of high energy output they do. However, the riders eat whatever they're cofortable with, and for some that means sandwhiches instead of "gels", though most do eat the specializied stuff.

As a note to tack onto that, a typical flat stage of the Tour takes about 6,000 calories (for the whole day), and mountain stage takes 9,000 to 10,000 calories. The human body can not absorb more than about 6,000 calories in the day, and that's if you eat constantly all day (which the riders do), so on the mountain stages all the riders loose enormous amounts of weight due to the fact that it is phsycially impossible for them to eat enough to replenish what they lost.

Hobbes [Smile]

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BannaOj
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Which I already knew, and is of course why they aren't worried at all about Lance being "heavy" right now. Tyler while I believe he is a lighter guy to begin with, might actually need to put on more weight before the Tour starts in order not to drain his reserves by the end.

That's also why they talk about "peaking" mid tour because of the energy reserves vs. energy expended to weight ratio.

AJ

[ June 18, 2004, 04:12 PM: Message edited by: BannaOj ]

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Hobbes
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A lead-out is done by someone who can go very fast on flat. A lead-out man will go top speed for a few hundred meters or less and then peel off and let the sprinters charge ahead (sprinters can go the very fastest on flat, up to around 70 km/hr for very short distances). The reason you need a lead-out guy is that if the sprinter were to try and just amble on down the course by themselves they would get passed before the finish. If they go fast, start sprinting early, then someone will hook onto their tail, ride their slipstream all the way to the finish, and then use the reserve energy they saved to burst past the person in front at the last moment and take the win.

So instead there's a lead-out man who will do that for you, someone who sacrifice's their chance at the win to let the sprinters take the stage. That's what is meant by a lead-out, leading the front of the group to about 100m from the finish.

Hobbes [Smile]

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aspectre
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"how do the riders go to the bathroom in the Tour?"

Bicycle shorts have padding which dry in the breeze.

[ June 20, 2004, 08:29 AM: Message edited by: aspectre ]

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Phanto
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It smells bad, yes, and feels bad, but efficency comes first. These people work hard at winning.

[Angst]

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Hobbes
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For the 20th:

Most big races have stages called "Time Trials". Le Tour has three different types. The main type happens twice, and is just a time trial. The riders set off every two minutes, seperatly (most race time trials it's one minute, but le Tour is two, don't ask). There are very strict rules about drafting, meaning if you catch up to the guy two minutes in front of you, you can not ride in his slipstream, nor vica-versa. This year, one of them is up a mountain, very unusual, most time trials are on mostly flat courses.

The second type is a prologue, which is exactly the same as the normal time trial, except much much shorter; normally in the one digit kilometers range. It (as the title suggests) starts the tour. There's the prologue, then stage 1-20, making 21 stages total.

The final type is the team time trial. This has exactly the same rules as the normal time trial except two things. Unimportantly, the start time differences are bigger, and importantly, the teams start off together, and you can draft within your own team. The time of the 5th rider of your team is the time the whole team gets, so often teams will drop some of their climbers (who can't go as fast on flat) to makes better time. This year a new (crappy) rule was put into place so that no team can loose more the 2:30 to the winning team, all teams will be within that range (meaning their time will be reduced, not that they will be eliminated if they don't make it).

Hobbes [Smile]

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Lalo
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Hobbes is like the big black cellmate in the prison of bicycling. I bow my trembling gringo head to his clear superiority.
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BannaOj
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Hey Hobbes, can I suggest that your next tidbit be on the energy efficiency involved in drafting? I doubt people realize concretely the difference in time it can make.

AJ

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Hobbes
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Aww, that's sweet Lalo. [Blushing] [Big Grin] [Wave]

June 21st
The basics of team and break-away drafting (Part 1.5: Line drafting basics)


The line draft is the simplest form of drafting, effective and easy to co-ordinate, as well as a good idea for smaller groups. To understand it better, I've created a series of very, very simple JPGs (and yes, I did them with paint, where I am now it's the only thing I have to work with, and it serves it's purpose just fine for this). Each circle is a bicycler, simple enough.

So let's go to the basics of the line-draft.

Figure One

Here we see the cyclists all lined up (meant as an explanation, not a pun [Smile] ). For the moment, ignore the red rider, we'll get to him. The blue rider is now in front, "taking a turn at the front", or "leading-out" the group (normally associated with leading out sprinters, this phrase gets a lot of other uses as well). He's creating a slipstream for the other riders, making their air-resistance significantly less so they have to do less work. The other riders simply stay behind him, within his slipstream. The closer they are the better the slipstream, but the more dangerous the riding becomes. How close the riders get depends on how they’re feeling, and what level of bike handling they’re at. The really experience pro-riders will get with wheel all lined up with barely a foot, and sometimes less, in between.

Now what happens when the front rider gets tired and needs to take a break? Well let’s go back to our red rider. He used to be the front rider, but he finished his “pull at the front” and is now in place for a break. He veers off to the side and falls back, letting the blue rider take out the lead. He then cruises to the back of the line and the pattern is repeated. The following figure shows the red rider latching onto the back:

Figure 2

How long these turns at the front last depend completely on the riders, the course, the wind, and just about everything else. They can last for minutes or seconds; sometimes they don’t last at all, where every time a rider makes it to the front and starts leading out, they fall back, in a continuous cycle. However, that turns into what is called “echelon” forms, and is no longer line drafting.

There are various things to avoid in this format, let’s see a few of them.

Figure 3

Here we see a rider who didn’t latch onto the back fast enough (the red rider). He came back to the end of the line and went too far. Now there’s a gap between himself and the rider in front, and as a result, he no longer gets the benefit of drafting. He and the front rider are doing equal amounts of work, for no gain. The trick to avoid this is to start accelerating before you reach the back. When you come off the group you go much slower than the others, letting them pass you by. To join on again, you need to accelerate back to their velocity. And you need to do that before you reach the back or you’ll loose precious feet while accelerating.

Now let’s look at another unfortunate occurrence.

Figure 4

Here we see that the blue rider has taken over the lead of the group; but now he’s surged. When you come to the front of the group do not accelerate! This is key, keep up the same speed, the rider in front will fall back, you do not accelerate by him. The blue rider here has screwed up and accelerated, the rider behind him did not accelerate at the same time (since that would require instant reaction time, which no one has), and when he accelerates, the rider behind him develops a gap. This goes all the way back to our poor tired red rider, who just finished his own, difficult lead-out. Now each rider is breaking a new slipstream for themselves, and not getting any benefit of drafting. Accelerating the lead-out is a big no-no.

Well those are the basics, later I’ll touch on signaling, lengths of pull, wind, and various other things.

Hobbes [Smile]

[ June 21, 2004, 06:37 PM: Message edited by: Hobbes ]

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Hobbes
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AJ, I posted before I saw your note, looks like we almost had exactly the same idea! [Eek!]

Hobbes [Smile]

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Hobbes
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June 22nd
Line Drafting II


So we’ve seen how the line draft works in basic conditions, let’s take a little more detailed look. First off, what happens when there’s a cross-wind?

Figure 1

This shows a lot of stuff. The first, and most noticeable thing is the way the riders are aligned (note: the green arrows represent wind). When drafting you always want to stay in the slipstream of the rider in front of you, and when there’s a cross wind, the slipstream moves. Let’s understand this a little better, and then get back to the complicated figure 1.

Figure 2

Here’s a hastily drawn picture of two riders, blue is leading out against the slip stream, and black is drafting behind him. The green arrows represent the direction of the force of the air pressure; as you can see, not only are not all of the arrows directly against the riders, some of them are pushing them forward! In perfectly laminar flow (basically, smooth flow) the air actually has no effect on an object, backwards or forwards! Well of course like many things, no one has ever achieved perfectly laminar flow, though it’s certainly been attempted (much of aerodynamics is to try and get the laminar shell to “attach” to an object for as long as possible, creating the least amount of drag, or “skin friction”). However, the back of something, even something that’s not perfectly laminar, will receive a forward push while the front is being pushed back. Two riders close together actually act like a non-laminar, single object. Meaning, that the back rider will get some push forward from the air.

Now this effect isn’t pronounced, and in our two rider system, the push backwards on the second rider is greater than the push forward (as they don’t act as a perfectly singular, laminar object), but you’ll often see guys at the back of the peleton (the huge group of riders, that bunch together for just this reason) coasting and keeping up. Of course at these speeds they still have to work to stay with the group, but the air is actually helping them go forward!

So now, let’s go back to the wind with another figure, and then return to our good ‘ol figure 1.

Figure 3

Here we see wind in green (on the blue rider), and the rider’s forward progress in black. There is a wind exactly opposite to that rider’s forward progress, pushing him back, and then there is the cross-wind. Figuring out the overall wind on the rider is simple vector addition. The rider has a wind on him with magnitude and direction equal to the green line with a black line through it. Simply add all the wind vectors (velocities) together to achieve the final wind. And directly behind that wind from the blue rider will be where his slipstream is (where the other riders want to draft).

So let’s go back to Figure 1. Keep in mind while looking at this picture that the black and blue riders (ha ha! [Wink] ) are all going straight up the page, not to the left! The brown lines represent the rider’s individual slipstreams, and as you can see, each rider (besides the lead-out blue rider, and the red rider who’s falling back) is in another rider’s slipstream, making their wind resistance significantly less.

One thing to note when riding in a cross-wind, the lead-out rider always pulls back into the cross-wind. This is because the rider behind him will be overlapping wheels on the other side, and if the rider pulls off away from the wind then the will slip wheels, and most likely fall.

The riders, when there is no wind, signal by flicking their elbow’s in the direction they’re pulling off (and when there is wind too, but it’s always a pre-determined direction). Then the rider behind them takes over pace-making (remember, no accelerating!) and the other rider drops back to the end of the line.

Hobbes [Smile]

[ June 22, 2004, 01:17 PM: Message edited by: Hobbes ]

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BannaOj
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*cheers* Go Hobbes!

Most team strategies start with drafting as one of the fundamental building blocks.

If one team wants to keep the race under their control so that breakaways of lone riders or small groups don't happen, they sacrifice energy to do so by setting a high tempo at the front of the peloton. You see, sometimes things are nicely organized and the teams will work together so that each team is sharing the time at the front equally so their riders don't get tired.

BUT, if a team decides they want to set a fast pace, they run the risk of all of the other teams hanging them out to dry. They will just draft to their hearts content, and let the attacking team expend far more energy and rotate their riders through without ever reciprocating. So the attacking team's riders either have to be better and stronger than all the other teams, or the extra fatigue at the end had better be worth whatever goal they are working towards.

This is why it is such a chess game. This is also why on breakaways you will see two or three riders of different teams working together. They've expended extra energy on the breakaway to begin with but if there is more than one of them, they can all work together with drafting (even though they will still be expending more energy than the peloton they can save quite a bit). But at any moment one can see an opportunity and attack and then the working together becomes a shambles. It's an integral part of the sport. No one generally gets upset (though every now and then something petty or nasty happens), everyone knows there is a time for working together and a time for going on your own and its part of the game.

Attacking acceleration speeds are amazing, but that's a different topic.

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Hobbes
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I'm curious if anyone besides AJ and I are reading this? Is Lalo still here? I mean these are taking a lot of work, and if no one else is reading them... well I guess I wont stop but my entries will start getting a heck of a lot shorter.

<--*Insecure*

And if people are reading this you should tell me, and possibly ask me questions, or answer mine on: do you want to hear about the echelon drafting technique?

Hobbes [Smile]

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Dagonee
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I'm reading it. I've got nothing intelligent to say or ask about it, but I'm reading it. [Smile]
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Hobbes
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[Cool]

A note on the import of drafting:
If you ever look at the bikes these cyclists race you may find yourself wondering how much they really help, how big a difference they make. And more importantly, how much would they help you if you could get your hands on these many thousands of dollars vehichles? The answer is: not a whole lot. You can get yourself a lot easier ride by switching from whatever you have now (of you don't know, it's probably a hybrid or a mountain bike) to a road bike. That'll get you in a lower position, and reducde friction with the road. But once you get to the road bikes, teh differences become smaller and smaller. The difference between a $1,000 bike and Armstrong's $9,000 bike (actually his time-trial bike is custom made and doesn't really have a price, that's an estimate, his road bike is, believe it or not, off the shelf, you can get it if you have about $8,000 around) is negligable for someone like me. Armstrong could, of course, tell the difference, and he'll save some meaningful time on his bike over what he would ride on a $1,000 one. However, were you to plop down on his time trial bike (assuming it was fitted for you) and start riding, you'd notice a difference, but barley.

And that's the way it is with a lot of things, in cycling and in other sports, you have to get really good before you start to notice the difference between things that you do, and things amatuers do. So a lot of people get the idea that drafting is like that, it makes a little difference, saves some time at the end, important maybe for those in an uber-competitive race like le Tour de France, but for the rest of us, it wouldn't really matter.

wrong.

At the speeds you probably go, actually, it may be right. You wont notice the effects of drafting at 10mph, you can get as close as you want but at that speed you just wont feel it. However, air-restiance is not linear; when you go twice as fast you do not go against twice the air-resitance. It's exponential, and as you go faster, the resitance from the air goes up dramatically. At Tour speeds (over 40km/hr for flat) the difference drafting makes is not just a side-note, it's everything. That's why teams are so important, they can take their leader and draft for him all the way, saving his legs. Drafting can create decreases in energy expendiatures by over 50%, it is not something to just consider, in all road races (like the Tour) drafting is everything.

[EDIT: I actually have a table with the energy differences for aero-positions, unfortunatly it's at home and I'm at work. As I recall, a standered sit-up bike (not a road bike) takes almost twice as much energy to ride at 20mph as a road bike when you're in the low position on it. Twice!]

Hobbes [Smile]

[ June 22, 2004, 04:42 PM: Message edited by: Hobbes ]

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BannaOj
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May I point out that this is why my contention that a mtn bike, maybe with slicks, would be more comfortable for (non racing) touring since with fully loaded panniers the difference in wind resistance between it and a road bike is negligible, and I don't think your road friction coefficient is going to actually be that much more even if it is based on contact surface area.

AJ

[ June 22, 2004, 04:48 PM: Message edited by: BannaOj ]

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Hobbes
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Have biking: try out aerodynamics!
Here's a fun way of seeing the difference aerodynamics makes on a bike. Go to the top of a reasonable sized hill (preferably with a friend) and go down without pedaling. As you're goin down get in the aero-position. You can do this even without a road bike, here's what you do:

  • Put your hands as close as you can to the middle of your handlebars
  • Put your head down right ontop of your hands
  • Stick your butt in the air and go!
You may feel silly, but watch as, without pedaling, you rocket by your friend. [Cool]
Here's a crude picture of the aero position.

AJ, I agree, but my two biggest gripes are the energy it takes up bouncing on the mountain bike (even without shocks, or tight shocks, the big, slack wheel takes up a significant amount) and then going downhill. Certainly it wouldn't have been that big a deal for the really slow touring we were talking about, but that was my preference. [Smile]

Hobbes [Smile]

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aspectre
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Yep, I'm very interested in reading all the stuff about biking. Admittedly, my additions thus far have been very tongue-in-cheek.

However, the power required to overcome air resistance increases proportionally to the cube of the speed, not exponentially.

[ June 22, 2004, 05:16 PM: Message edited by: aspectre ]

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Hobbes
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The key there is that the air-restance increases quadratically, and then that's just force, and power is force*speed. So if

Force = a*v^2 + b*v + c

where 'a', 'b', and 'c' are constants, and v is the velocity, than when you see the equation:

Power = Force*v

You can do a rough approximation substituting v^2 (the dominating factor in the first equation) for force that's basically this:

Power = v^3

And you see that Power is at least proportional to the the velocity cubed, and power is always the key.

Hobbes [Smile]

[ June 22, 2004, 05:18 PM: Message edited by: Hobbes ]

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Hobbes
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By the way, here's an explenation for why the force of air-resitance is the square of teh velocity (I came up with this indpendantly, so I guess I may be wrong).

Air-resitance is just getting hit by a whole bunch of very, very small things (air molecules). You can visualize as being hit by a baseball (only if you're going that fast, slow down!).

Only to avoid some perhaps painful memories from Little League, lets get a little more realistic, and picture the basball standing still (in mid-air somehow) and you running into it, however should you be standing still and have the baseball thrown at you the effect would be the same, feel free to imagine it that way).

So you're running along at 5mph and all of a sudden: BAM! You hit the baseball. Well you're baseball-resistance (metaphorically to your air-restance) is now one ball at 5mph. You keep going and find that there's a baseball every (approximatly) one foot of space you run (ouch!). So now you're hitting a baseball once every time unit (let's say it's 1 second, I don't want to actually figure it out). So every second you impact a baseball at 5mph.

Now you double your speed. So you're going through twice the distance every second, which of course means that you're hitting twice the number of baseballs as you orginally were every second (two). Not only that, sicne you're going faster, you're hitting each one twice as fast! So when you were orginally going 5mph, you were hitting one baseball at 5mph, now you're hitting 2 baseballs at 10mph! 4 times as much work now.

And that's why it's squared for force, when you go twice as fast you hit twice as much stuff, and hit it twice as fast.

Hobbes [Smile]

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BannaOj
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If something is proportional to the cube or the square of something else, it is an exponential curve. the first is F=kx^3 and the second is F=kx^2 By definition since is being raised to a power greater than one, both are exponential curves. (a logrithmic curve comes from an something being raised to something between 0 and 1, and negative logs involve imaginary numbers)

See hobbes, you didn't need all that mumbo jumbo [Wink] . And all of your mumbo jumbo could easily be explained with calculus though I realize you didn't want to do that.

AJ

[ June 22, 2004, 05:49 PM: Message edited by: BannaOj ]

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Hobbes
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Incorrect, I want to do it, no one wants to read it. [Wink]

Hobbes [Smile]

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aspectre
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Let k = the constant
and x = the variable
Then geometric growth is eg x^k or x raised to the k-power
and exponential growth is eg k^x or k raised to the x-power

eg let k = 3
Geometric:
If x = 1 then x^k = 1^3 = 1 times 1 times 1 = 1
If x = 2 then x^k = 2^3 = 2 times 2 times 2 = 8
If x = 3 then x^k = 3^3 = 3 times 3 times 3 = 27
If x = 4 then x^k = 4^3 = 4 times 4 times 4 = 64
If x = 5 then x^k = 5^3 = 5 times 5 times 5 = 125
Exponential:
If x = 1 then k^x = 3^1 = 3
If x = 2 then k^x = 3^2 = 3 times 3 = 9
If x = 3 then k^x = 3^3 = 3 times 3 times 3 = 27
If x = 4 then k^x = 3^4 = 3 times 3 times 3 times 3 = 81
If x = 5 then k^x = 3^5 = 3 times 3 times 3 times 3 times 3 = 243

Examples of geometric growth would be the increase in the area of a square as the sides lengthen or the increase in the volume of a cube as the edges lengthen.
Examples of exponential growth

Cubing (as represented by ^3) is a geometric process. In this case, if we let
oS = originalSpeed
nS = newSpeed
oP = originalPower requirement at the oS
nP = newPower requirement at the nS
Then nP = [oP] times [(nS/oS)^3]
or nP = oP times (nS divided by oS) times (nS divided by oS) times (nS divided by oS)
in the simplest "consider a spherical cow" form.

- - - - - - - - - - - - - - - - - - - - - - - - -

Lots of editing cuz eg K and X look too much alike when jammed together, etc,
and 'velocity' means 'speed and direction'

[ June 23, 2004, 04:01 AM: Message edited by: aspectre ]

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DSH
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Forget air resistance, tell me what happened to 700A and 700B wheels. [Dont Know]
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advice for robots
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Hey Hobbes, I've been reading with great interest. I loved your explanation of last year's Tour de France and you've made the whole race make a lot more sense to me by explaining drafting. I always wondered why they seemed to ride in groups like that. You're revealing a lot of strategy in bike racing that I didn't know existed. Keep it up, if you're up to it!
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aspectre
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Gotta agree. It was a lot of fun mentally accompanying you and your father on your rides. Same with seeing the Tours through your eyes.

[ June 23, 2004, 03:57 AM: Message edited by: aspectre ]

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Hobbes
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First off, aspectre is competely right about it being geometric, not exponential. I have a life-long habit of using exponential when I mean geometric (geometric just sounds linear to me, I can't help it I swear!). So anyways, yes, air restiance eats up your power cubicly, or on a geometric level relating to velocity. [Cool]

And second, thanks everyone for the encouragment, it's grea to know people care. [Big Grin] I'll post an explenation of echelon drafting sometime today. [Cool]

Hobbes [Smile]

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BannaOj
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Yeah, aspectre, I stand corrected. But in most math classes I've been in, the profs don't even use it correctly!

AJ

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Hobbes
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Ohh, AJ said exponential too, I didn't even notice. Must be an engineering thing... [Wink]

Hobbes [Smile]

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Hobbes
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Fun tour fact of the day: Armstrong's standing heart rate is 32 beats per minute. Doesn't that just brighten your day right up? [Wink]

Hobbes [Smile]

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Hobbes
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June 23rd
Echelon drafting


This more complicated than simple line drafting, and more effective. Hopefully it’ll be simple enough to understand, but unless your really going strong on your bike with at least 8 (and better with more) riders at similar levels, this one will be more for you to understand cycling than to practice, because putting it into play is much more difficult than understanding it. Let’s start out with a fun figure, one that should show all of what’s going on (should being key [Smile] ).

Figure 1

Let’s start off with the right side, the yellow rider is in the back, blue in the front. Think of each side as individual line drafts. So we have blue leading out the line, with yellow in the rear. On the left side we have red leading out the line with purple in the rear. There we have the basis of echelon drafting, two line-draft lines right next to each other.

Simple enough, right? Well let’s move onto the more complex part of it, first, look at the black arrows on top and bottom. Red, it appears, has just moved over into the left lane (I’ll call them lanes from now on) from the right lane. It’s exactly the same move red would make if he were in the right line draft and just finished the lead-out (so think of him as now dropping back to the end of the line to work his way back-up).

Purple is about to switch over into the right lane, get back into that draft and work his way back up to the front. Simple enough so far, at least if you look at it separately. Now let’s take a look at what blue’s doing. Red just dropped out of the lead and fell into the left lane, so blue is clearly taking over the pace making. Only he’s also moving over from right to left. What this means is that no one takes “pulls at the front”, as soon as a rider makes it to the front, they move to the left, and the next rider comes up and move to the left. This means that the riders will only be breaking the wind when they’re moving over, never taking durations of lead-outs.

And finally, let’s look at the big arrows for either lane. The one on the left is point backwards and labeled 25mph, the one on the right it forwards going 27mph. This does not mean the left lane is moving backwards at 25mph! It means they’re moving forward at 25mph, but since the right lane (fast lane) is moving two miles an hour faster than the left lane (slow lane), the overall effect is that the slow lane riders are dropping back in comparison to the fast lane riders. Here’s the best way to visualize this:

Figure 2

You’re a biker on this big tread like thing (the oval). You keep going around and around and around, on one side you’re going 1mph forward, on the other you’re going 1mph backwards, and you just go around like that. However, at the same time, this whole oval is moving down the road at 26mph, so your total speed is 27mph on one side and 25mph on the other. Can you visualize it now? If not, ask questions!

This type of drafting is incredibly effective, especially in cross-winds, because then the slower side (always on the side the wind is coming from) will break the wind for the fast side, which is handy since you don’t have to do as much work on the slow side normally. Also, no one takes long pulls at front, everyone starts moving back the instant they hit front, so no one gets worn out if they spend too long pulling. And finally, instead of losing all that time where a rider will basically just drift to the back of the draft-line, they pedal now, and go fast, so their time is actually spent moving forward, not de-accelerating and then re-accelerating.

Hobbes [Smile]

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Hobbes
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Any suggestions for topics to touch on today? I've pretty much finished drafting, unless you count break-away attacks as being part of that.

Hobbes [Smile]

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BannaOj
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Well there's echelon drafting expanded to the wedge that exists in the peloton.

Maybe go more into tactics?

AJ

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Hobbes
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June 24th
Breaking Away


You’re riding along in a typical group (we’ll make it small for now, but the break-away tactics themselves are pretty much the same all through-out), and all of a sudden, you decide it’s time. Your legs are feeling good, you’ve noticed a slow down in pace, whatever: you want to go now! So how do you do it? How do you create a break-away? Well let’s start by looking at the situation with a good ‘ol figure.

Figure 1.

You’re the red rider, blue is leading out the group. You’re in the very back of the group for now, you’ve gotten a little rest there (hopefully) and are ready to go. The way to start the break away is to drift back. One of the key elements of a break is surprise, that’s why you start at the back, and that’s why you drift back now, so when you blow by the group they wont realize it until you’ve already accelerated.

Figure 2

There you are, you’ve drifted back and a bit to the side (so you can accelerate by them, if there’s crosswind, you’ll always go on the opposite side incase the leader pulls out just as you go by and crash, and because then you’ll get a little extra wind protection). Now you begin to accelerate, and hard. This will not be pace you can keep up, but you need to put definite space between yourself and the group, so you jump on the pedals and go!

Figure 3

And you’re off! By the time you’re back up with the group, you should be going much faster than they are. This way when they see that you’re going, they have to work to catch up. No one can accelerate instantly, so you’re guaranteed at least a few seconds on them by virtue of your much higher speed. It makes it much more difficult for someone to try and jump on your wheel and draft off of you as you go by.

After you’ve jumped past the group, you’ll have to keep your speed high for a little while, make sure a big enough gap develops that they can’t draft you, and preferably, big enough that they can get back to you for the rest of the race. At some point you will have to slow down since you can’t keep your break speed up for the whole race (if you can, you’re going to slow!) Once this has happened, there is no strategy left for you, either you can tough out to the end of the race, or you can’t and the group behind you catches you.

So let’s go back to the group, and see what they can do to react. First, the biggest mistake that is made in catching a break-away:

Figure 4

Here the red rider has gone, they’re in front of the break, and now the group has to chase him down. It will start with the front rider accelerating, and then the rest of the group has to go or be caught out. What we see happening here is that the blue rider has sped up, but the other riders sped up to slowly. They waited for the rider in front of them to start accelerating before they did, and that means that between each rider is a gap the size of their reaction time. Now the group is split up, and each rider is facing the wind by themselves, instead of creating an effective line-draft. The trick is to start accelerating the instant you see the lead-out man going, this way everyone accelerates at exactly the same time, and no gaps form. It’s tricky, but it’s all part of being a professional racer.

So that’s the main mess-up, now let’s look at the ways to effectively control the break. There’s two main tactics you can choose to do so, and let’s start with the individual one.

Figure 5

Here the red rider goes again, and blue is leading out, but this time you’re yellow. You notice red coming up behind you, or going past you, and you decide to try and catch him. You jump out of line and start accelerating as hard as you can to get on Red’s tail.

Figure 6

You make it! Chances are you’d have caught onto red’s tail a little slower than this picture would show, but only by a few meters down the road. Now you’re in red’s slipstream, and you’re drafting off him. This means you can follow his break (probably) and not do as much work. Now one of three things will happen: he’ll realize he’s caught and slow down to return to the group, he’ll decide that even with you in his slipstream, he can still loose you, ant try to continue the break (at a high velocity to try and get you to fall off his tail), or, he can decide to break with you. If he does the first thing, you can try your own break off of him, or just go with him. If he does the second, you’ll just have to try and hang on, and if you do, you’ll end up with fresher legs than he has since you were drafting. If he does three then you can work with him to get this little break to the end of the race. That means two person drafting (if someone else breaks with you this is exactly the same for all of these possibilities, just a bigger break now).

If you try to catch onto his wheel and don’t make it you have to either give up and go back to the group, or try your own break-away behind red’s. But what if no one catch’s red’s wheel and he breaks alone? Well you’ll try to bring him back (catch up to him, otherwise he’ll win the race!) and you’ll do it in the group. This is more typical if you’re in the peleton with a hundred other riders, but it’s still very standard for small groups.

You don’t need a picture for this one, because now we’re back to the line draft. What’ll happen is that the group will pick up their pace. They wont accelerate to the speed of the red breaker, he’s going faster than anyone can really catch up to. What you do is let him break, give him some distance, but keep the tempo high. It’s using the fact that you’ve got multiple guys there to draft from and he has to fight the wind the whole way. Basically you hope that as a group you can keep a speed higher than his to the end, and then you’ll catch him out.

As a note, when most break-aways are caught by the group this way, the breaker (red) will fall behind the group. A break takes a lot of energy since you have to fight the wind the whole way by yourself, and a break-group is much fresher since they can draft, so chances are they’ll “drop” you if they catch you. Meaning pass by you and you wont be able to hook onto the group.

Hobbes [Smile]

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Hobbes
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I don't have a whole lot of time today, and I will have none tomorrow through Monday, so umm... ponder my (long) post from yesterday.

Tour Tidbit: In the early Tours it was considered essential to smoke while riding, it supposedly "opened your lungs".

June 25th
The Tour Way Back When


Orginally the rules of the tour were incredibly strict. No help from anyone. To speak nothing of a team care trailing behind, you weren't allowed help fixing flats, finding sleeping accomidations or even dinner. One year during these rules, a rider, prominently in the lead, crashed miles out of a town. he broke his fork completly. So what did he do? He walk the miles to town with his bike where he took over a local welding shop and spent four hours welding his for back together by himself. This is a far cry from today's Tour, where each rider has spare bikes for each stage, and several mechanics.

Hobbes [Smile]

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Hobbes
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If I have time before the Tour starts, I really want to talk about blocking, but that can be rather complicated, take drawingings and lots of time. But you never know. [Smile]

June 29
The jerseys


The Yellow Jersey
The leader in time. Each day your time is clocked individually for that stage, and your total time on the tour is added up by simply adding all those individual stage times together. It can get a bit more complicated due to the fact that winning the stage, or one of the intermidiary check points can some times get you time bonuses as well (ever single finish has 20 second time bonus for first, 12 seconds for second, and 8 seconds for third), but really it's as simple as you think it would be. The resulting ranking (whose total time is the least) is called "The General Classification", and often reffered to as the "GC". Leading the GC means wearing the yellow jersey. A new one is given out each stage for whoever leads the GC at the end of that stage. So whoever is wearing yellow is winning the race, it's that easy.

The yellow jersey appeared a few years into the tour, it was the main color of the paper that began sponsering the tour.

Green Jersey
This is the sprinter's jersey, it's a little more complicated. Each stage has checkpoints through-out it, and each time there's a major check-point, there's an "intermediary-sprint". Points are given out based on where you finished in each one of those sprints, and more points are given out based on where you finish in the stage finish. These points wont get you anything in the GC, but they are what determine the Green-Jersey competition. That's why the sprints are so important, even though the people at the end of the pack get the same time as the sprinters in front, the points are different, and he with the most points wears green.

Polka-Dot Jersey
This is the King of the Mountains jersey, or KOM. It is incredibly similar to the sprinter's (green) jersey, but instead of just having "points" determine the winner they have "mountain points". Exactly the same concept, except instead of awarding these points on the flat checkpoints, they award them based on who got to the top of a mountain first, and the number of points awarded to the first-place man is based on teh difficulty of the mountain. So summary of polka-dot: it's sprinters in the mountains.

--Those are the main jerseys that people care about, but there is one other that's awarded

White Jersey
This is given to the best rider (determined strictly by their GC classification) who is under 22 years-old. The young rider's competition.

There are a few other jerseys that were given out last year in honor of the fact that it was the 100th year anniversary of le Tour, like most consistant finisher in stages that ended in cities that hosted the very first Tour, and most aggresive rider, but they wont be back (to my knolwedge).

Hobbes [Smile]

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Farmgirl
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Ummm.. I think you just answered my question in that post. I was always wondering on a multiple-day race, how they determined who was in the lead (I see you say they time each day for each cyclist). So how do they all start out the next morning -- all together with the leaders in front? Or can they start whenever they wish since they are being timed individually? Is everyone part of a team? Are there no solo riders?

Farmgirl

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Hobbes
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Ahh, good questions! [Big Grin]

The riders, like I said, are clocked each day indivdually, and there total time racing is simply added up for each stage. However, all the riders start together in one gigantic group, even if one rider is 2 and a half hours ahead of another rider, they start at the same time. They must start when everyone else starts (I suppose they may be able to be late, but they would be given the starting time of everyone else so... yah. Though one GC hopeful was disqualified when he slept in and missed the start of the team trial [Evil Laugh] ).

quote:
Is everyone part of a team? Are there no solo riders?
The Tour organiziers invite teams to le Tour de France. They pick 22 teams based on how good they are, and how seriously they think they'll take the Tour (each team is then responsible for bringing 9 riders of their choosing to the Tour). The USPS team, for example, is a shoe-in, since they are the best team out there, and their focus is the Tour. However, some suprises do occur. Last year all bloody-hell was raised when the Tour organiziers didn't invite Mario Cippolini to the Tour. Mario was, at the time, the world's priemere sprinter, and he figured he had to be invited. But the organiziers were ticked that every year he would come, win a lot of sprints early on, then drop-out as soon as the mountains came, never bothering to finish the race. It's the organizier's perogitive who they invite, but certain teams are expected to be there.

So in answer to your question: no, no solo riders. USPS was invited, but not Lance Armstrong. They could've choosen to leave him off of the team (which of course, would've been ridiculous but they could've done it), and the race organiziers couldn't do anything because they only invite teams, not people.

Hobbes [Smile]

[ June 29, 2004, 02:35 PM: Message edited by: Hobbes ]

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pooka
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Hobbes, I do read but not daily so sometimes I have some catching up to do.
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Farmgirl
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Have you ever got to actually attend the Tour de France in person, Hobbes?

FG

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Hobbes
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You really know how to a hurt a guy Farmgirl. [Cry]

Hobbes [Smile]

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BannaOj
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To add a point on timing.

If your front wheel overlaps with the rear wheel of the person in front of you (if you are looking from the vantage point of the a person standing at the finish line looking across or the camera that takes photo finish pictures) You recieve the same time as the person in front.

So if the peleton all comes in as a group, and there is no one out in front so far that they are actually separate from the pack all riders recieve the same time for that stage.

The on flat stages sprinters that go out in front at the end of the day could break away slightly from the peloton at the end and gain a couple seconds as a result, but it normally isn't very significant in the grand scheme of the GC after the first couple weeks.

Also there used to be (and I think still are) time bonuses given as you go through checkpoints as well. So if you are first at a sprint or mountain checkpoint, not only do you get points towards the mountian or green jersey, but you also get seconds deducted from your overall time. The time bonuses are based on a sliding scale depending on the difficulty of the climb or sprint and number of points given. I'll try to find a list for them.

AJ

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Hobbes
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Time bonuses are given through-out the stage, but they're all much smaller than the final time bonuses (around 5 seconds, some a little more). Like AJ said, the actual magnitude of the bonus given is based on the difficulty of that checkpoint.

Hobbes [Smile]

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BannaOj
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I went to the official tour site and Article 26 of the rules regarding Time Bonuses is blank in both spots. I'm not sure why.

AJ

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Hobbes
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Well it's not that critical, it's up to the organiziers what the bonuses will be, and the Tour organiziers aren't exactly infamous for setting down rules to limit their freedom of action. So I doubt there's be a whole lot in the rules about the time bonuses along the road.

What'd you think of my break-away explenation?

Hobbes [Smile]

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