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| Speedboarding (19049 Posts)
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Speedboarding |
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road grades
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On 8/30/2000
hugh r
wrote in from
(205.216.nnn.nnn)
I have started to do a little more research on road grades as posted on signs etc... I was looking at some of the bike pages and it is looking as if most of the claims of extremely steep grades (25-30%) are highly exaggerated.
I will do the math later and will try to come up with an example that shows how steep a 25% grade over a given distance would be. Probably too steep to want to walk up. I will post more later... HR
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Aerodynamics
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On 8/30/2000 T Naylor
wrote in from
(209.208.nnn.nnn)
My brother was the last person to win the X games downhill rollerblade competition. The next year they discontinued it. Though different in terms of gear and stance than skateboarding, the race was significant in terms of exemplifying aerodynamics and strategy. He was the only racer in complete aerogear: a speedsuit from ski racing, calf fairings, a tear drop helmet, hubs, etc. In essence every bit of surface exposed to the wind was shaped and smooth. Not a bit of rough anywhere. When it came to strategy, while everyone fought to get the hole shot, he struggled to get behind the pack. Then at the crucial moment he would use the lead packs draft to slingshot way ahead. Each race , he crushed the competition. The biggest rub and probably the reason they discontinued it was that at 40 years old he was the oldest X game winner. Anyway, I'm getting him on a deck now. Who knows?
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9% grade
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On 8/30/2000 Herbn
wrote in from
(208.192.nnn.nnn)
A fun hill,but if it were a hundred miles long it wouldn't be all that fast,i saw a grade sign on rt515 into Vernon N.J. that said 17% and Breakneck ridge rd., which merges near the bottom has a longer section thats 20%,surface quality it a problem on Breakneck and traffic can be a problem on either of these roads.But comparing them to roads i do skate i think it would take smooth aerodynamics to get near the fifties on 515 and hypothetically jeans and t shirt could get you there on Breakneck. I'm gonna guess that the record that exists today,was done on a street with a rather long 22-23% grade with a good lead in,and of course with aerodynamics in the top percentile.Find a road with a 25-27% grade that goes for a while with a nearly as steep lead in, smooth surface, and the best aerodynamics and 70-72 mph shouldn't be out of the question ,equipment is cheap compared to the price of that road, cause i don't think they make them that steep,so your gonna have to make it yourself.By the way, i'll speculate once again, that the pavement in Himalayas at or around 18,000 feet is not all that skatable.
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Drafting a vehicle
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On 8/30/2000
rogerj
wrote in from
(32.100.nnn.nnn)
Drafting vehicles is pretty common on bicycles. I saw some salt flats footage of a racecar pulling a large sheet of lexan behind it like a parachute. A few feet behind the plate was a specialized "longbike" with huge sprockets. Driver and cyclist where in close communication getting speeds close to 150mph (I think, not sure).
Clearly drafting vehicles is a different category of skateboarding (draftboarding?) and specialized driving skills would be needed (easy with that brake). But it is fast, and it is on a skateboard. Ah hell, just put a rope on the bumper and hang on (mantis position). The possibilities for stunts are endless, but not quite the elegance of aerodynamics.
rogerj
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Tucks
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On 8/29/2000
danny connor
wrote in from
(205.188.nnn.nnn)
Hey fellas,
You know, I was wondering what was up with the praying mantis. It maks sense to me though. Eventhogh it's slower, I'll still do it because it is more comfortable on some hills, and it is fun. Has anyone tried the Landyachtz Dh for a speedboard? it's really cool. Well, it's past my bed time, I'll talk later.
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Speed records 101
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On 8/29/2000
Chris Chaput
wrote in from
(63.168.nnn.nnn)
For those who have not yet navigated through the speedski sites, I have put together a little crash course on the subject at:
http://www.chrischaput.com/homework
I think Herbn is right about bellbottoms and location. Did you notice the bellbottoms on Philippe Billy?
It appears that the world record holder Harry Egger is looking for more speed and is planning to raise his existing record of 248 km/h to an unbelievable 270 km/h in the Himalayas. The high speed adventure would take place at an altitude of over 6,000 metres. "The thin air admits distinctively higher speed..."
Although drafting could improve speeds, how'd ya like to drop into that Red Bull ramp playing grab ass with yer buddy? A speedboarding tuck attempts to get air to move cleanly around the body and legs but a speedskiing tuck moves air around the body but THROUGH the legs. A speedboarder may find that triangular foam piece between the back of the leading leg and the front of the trailing leg along with a trailing calve fairing may clean up the air passing around the legs. After the steepness of the hill max's out, you gotta reduce friction, get aero, get elevated or get out of the game.
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hills
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On 8/29/2000
hugh r
wrote in from
(205.216.nnn.nnn)
DT/Chris,
Check the hill on my page in Elisabeth Lake... this one is a bit longer than the dump and almost twice as steep. There is a run off, then a short down hill and then another huge run off. I believe that this hill is capable of speeds as high as you'd like.
Also, outside of Bakersfield there are a series of roads (esp the one that turns into FR43 or 46, something like that) that are many, many miles long and in the 9% grade range. These may be worth a look too.
Now I am no scientist, but I do believe that a nice 200 lb sack of potatos running on a wire could hit over 70 mph on the E-lake one at least... way, way, way too fast for this old scared guy!
If your interested in checking them out let me know and lunch is on me... HR
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Steepest hill in southern hemisphere
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On 8/29/2000 Nick
wrote in from
(203.96.nnn.nnn)
New Zealand has the steepest hill in the southern hemisphere. It has steps along the side instead of a footpath. I,ll find out more.
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high speeds
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On 8/29/2000
DT
wrote in from
(192.189.nnn.nnn)
I believe the hills that are used for speedskiing come from the sheer face of cliffs after an avalanche when its all smooth and almost vertical, there are no roads that come close to this, or are there. I know of two that have yet two be skated, but have the potential of braking 100mph. These hills are 26% and 27% grades, but they have turns that are too hard to manage with the eqquipment we now use. I have been told that 27% is the legal limit in which a hill may be built, but i may be wrong.
Also i forgot to mention that the praying mantis style of riding is SLOWER than the more traditional tuck in terms of aerodynamics. This has been tested and proven. You may ask why Manu Atuna is so successful and this is due to a key element, COMFORT. Manu has been a great boardercross snowboard racer for almost 10 years and is very comfortable in that position. This position also allows one to transfer into a slide with less ease and more quickness than a traditional tuck. He is also a superb racer and knows what lines to take while racing, his experience is very deep and in my opinion he is one of the best riders in the world, if not the best.
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Speed Records
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On 8/29/2000
GBJ
wrote in from
(205.177.nnn.nnn)
...and maybe that's the revolutionary, never-considered answer. Speed record holding by team! Sure, we can keep adding "kickers" to the tops of fast hills, to eek out another .5 mph, but maybe assaulting the records in drafting-teams is an alternative answer. It is beyond reason to imagine that skateboarders will ever find speed venues comparable to those used by the speedskiers. I, for one, wouldn't mind having a partner's name mentioned alongside mine, if I were going to be in the record book.
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High Speeds 2
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On 8/29/2000
Chris S
wrote in from
(208.164.nnn.nnn)
DT,
Thanks for clarifying that. It saved me the trouble of having to do it myself. The way people were talking it almost sounded like Gary set the world record on a set of old rusty bearings. One additional point, I got the impression from Gary that the Guinness event was just one person shooting the hill at a time. You're right that Gary and others have gone faster than the world record of 62. I may be wrong here, but I would guess that in most cases that would be a small group of guys drafting off each other and building more speed than a single guy alone on a hill ever could.
Finally, Herbn makes a good point about roads being designed so that cars can make it up them, not so that skateboards can break records going down them. To go significantly faster than the record under Guinness conditions, you would need a road that is much steeper than the public autoways.
Chris
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high speeds
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On 8/29/2000
D.T.
wrote in from
(192.189.nnn.nnn)
Let me set several things straight. Gary's record was not an accident, but an event put on with Guiness Book of World Records. Although he went 62mph on that hill, it doesnt mean that 62 is the fastest you can go on a skateboard. Many of us have all gone faster than that (Gary has already broken 70.) And Gary WAS NOT riding abec 3, he was riding what he always rides Swiss Bones (yes they were over 1 year old, but that isnt always bad). The hill they were riding had a top speed of around 59 on a skateboard, they added a 10ft roll in ramp to get those 3 extra mph.
Many say that being aerodynamic in your tuck is key to being the fastest, but many times the fastest are the most COMFORTABLE.
Chris has said a lot of accurate statements about the attitudes and needed technical advancements regarding racing equippment. Too many people are stuck in the old ways of thinking and that is fine with me. This will be the last time i mention this. The times in the races are so close that it will take little things to make one faster, and one of those little things are your gear. Those that sleep on these little things and rely on rider ability will be overtaken by the racer who has done their homework. This may not happen this next race, or this next year even, but it will happen. Maybe its something small that will be kept a secret for a long time, or maybe it will be some new expensive high profile bearing or wheel. Many riders may not know what hits them, or maybe all the riders will follow the trend. we'll just have to wait and see.
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Mini misers
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On 8/29/2000 Craig
wrote in from
(196.34.nnn.nnn)
All the physics of this bearing thing has me confused as hell!!??!!...I'm a big fan of dirty old rusted bearings, which spin faster than they ever did when they were newer...granted that top top class, in anything,usually revolves around subtleties, which the lower plebs would normally not take note of..yes i know. But i think that there is no point in worrying about the subtleties of expensive equipment until you have your tuck, and general style sorted out to the best of your ability.
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AERODYNAMICS/OPTIMIZATION
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On 8/29/2000
Craig
wrote in from
(196.34.nnn.nnn)
Okay, i was asking this a while back, no one has really passed any opinions...this debate has mentioned aerodynamics a lot...so what do you guys think is the best tuck, Danny O says it makes no difference, Butt-up, or "praying mantis"(?) style (MY girlfriend doesn't bite my head off when we have sex). If you want to skate 240% as fast as Gary (a speed at which, i can guarantee you i would fall), you should work out the best tuck, and probably be designing your equipment around that!!!!
By the way...I gave beginners luck a go about a year and a half ago: I raced in a race with THE best equipment of anyone's who was there (=36" flexdex, 70mm red kryptos, bones swiss, and indy 180's). My tuck left much to be desired (Check downhill longboarders (yahoo club) pics)...Basically i almost killed myself and everyone else on the road...I did come 5th...there were about 4 skaters there who actually knew what they were doing...
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Say nay
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On 8/29/2000 Herbn
wrote in from
(208.192.nnn.nnn)
I'm not a naysayer,optimize all you want,but i think that 62.whatever mph was real close to optimal, aerodynamicly and on asphalt that was pretty much as steep as it gets(as a street)so to beat that record by any significant amount,something extra is gonna be needed.I'm not saying Chris Chaput is to inexperienced to do it,but i think special terrain will be the key.3L's location,location,location.
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The Crush
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On 8/29/2000
Chris Chaput
wrote in from
(63.168.nnn.nnn)
When I go on a hill that has the potential for crushing the record I will be holding the best tuck that I can in all of the aforementioned aerodynamic gear and will use "Mr. Raver-bellbottom-puffy-shirt-Abec-1-bearing-man" as a parachute.
I can't quite understand what part of the word "optimize" is being missed here, so here are some dictionary definitions:
1. To make as perfect or effective as possible.
2. Computer Science. To increase the computing speed and efficiency of (a program), as by rewriting instructions.
3. To make the most of.
optimize v 1: exploit fully; get the maximum use out of 2: make optimal; get the most out of; use best
Take a look around you out on the highways today. Trucks, cars, trailers, the tailgate of your pickup, bumpers, mirrors, everything you see is being designed to pass air more cleanly over its surface. Gravity based vehicles don't have a motor to accelerate them and are therefore more dependant upon taking advantage of every physical enhancement possible to set them apart from the pack.
All of you naysayers had better pray that I don't win any races soon because when I do, you'll have to convince yourselves that this rookie has "superior riding ability" or that the aerodynamic gear gave me a competitive advantage. Although I could live with either explanation, the truth is that I have less experience than ANY racer out there, bar none. Oops, I just opened the door to "beginners luck".
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Record
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On 8/29/2000 Herbn
wrote in from
(216.107.nnn.nnn)
If you went up and paved the hill that those 240% faster speedskiers went down, you could probabely "crush" Hardwicks speed record in raver bellbottoms and a puffy shirt with Abec 1 bearings ,or at least make some interesting splatter art.
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homework
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On 8/29/2000 brian-DE
wrote in from
(206.105.nnn.nnn)
i think what herbn was trying to say is: for any given hill, there is a maximum speed you can travel, no matter what you do. tucking, aero gear, whatever, can only get you to that speed, therefore in order to reach higher speeds, you need a bigger hill.
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yoga teachers
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On 8/28/2000
Dan Gesmer / Seismic Skate Systems, Inc.
wrote in from
(152.163.nnn.nnn)
Denis Schufeldt, one of the pioneers of mid-1970s downhill skating and noted for his progressive body faring techniques, was just that: a yoga teacher.
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Do your homework
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On 8/28/2000
Chris Chaput
wrote in from
(63.168.nnn.nnn)
Gary's own words "It’s all about being aerodynamic" speaks volumes. Read his interview about the hill, equipment, etc. then go to:
http://www.streetboards.com/sb/report.html
Gary's helmet is a Jarret Ewanek - Dr. GoFast - Dregs. It is a knockoff a 1972 German speedskier's helmet. Today's helmets are simply faster. PERIOD.
If you want to learn about people who routinely go over 240% faster than Gary's record then PLEASE go to:
http://www.speedski.com and for the ramp/hill checkout
http://www.speedski.com/WorldRecord1999.htm
Look at and listen to the World Champions like Jeff Hamilton who repeatedly state in their own words:
4. Get aero
An aerodynamic set-up is the single most important thing about your speed skiing, other than your tuck. One, get yourself a speed helmet. They can be about $1000 but they make all the difference...
Please tell me where it says that "aerodynamics and friction are not important, it's all about the hill".
If one were to have listened to select statements on this website he would have heard that aerodynamics, helmets, leathers, bearings, density of air, a low center of gravity and decreased friction DON'T significantly help in increasing a skater's speed. It appears that the only thing that matters is RIDER ABILITY and the size of the THE HILL. Even though I completely understand the spirit of a statement such as this, I think that this is an old pervasive skateboarding attitude that can only serve to keep us in the dark ages for years to come. When the hill is the same for all riders, a rider's ability is used to obtain a good tuck and to maintain it and a yoga teacher with a good start would do better than a "wildman". Over a period of time, we will see whether the rider who leads with the BIG HELMET goes faster than the rider who leads with the LITTLE HELMET.
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Speed
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On 8/28/2000
Danny Connor
wrote in from
(205.188.nnn.nnn)
Hey speed demons,
This ALL seems very strange to me. Gary said himself that his acheivement of the record was a sort of accident. He just bombed the hill. It seems to me, that a skateboarder can only go so fast, reguardless of what hill and what bearings. The reason I say this, is because, when I am in a very low praying mantis tuck, I go just as fast as when I am in a more conventional "head down and butt up" tuck. But then again Chris is talking about using fairings and such, wich could have an effect that could only work at high speeds. You also always see dudes beat others who have crappy bearings and small wheels, figure that one out. Whatever. Chris, if anyone can get this it's you. Sorry if I am just talking out of my rear with this post, but it's just what I think.
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Max speed
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On 8/28/2000 Herbn
wrote in from
(208.192.nnn.nnn)
Hey,that hugh, such a trouble maker:)with his giant bearings,Chris sort of missed it too,i'm talking about the ratio between the ball size and the race,i think its the outer one thats important. that determines the speed of the ball and the ratio can make a smaller bearing harder to accellerate,if minimizer ball were small enough they might even spin faster than regular balls,meaning higher start up ratio,which probabely would be cancelled out by the lower weight, but it is a factor that decreases the possible advantages of these little bearings.Lets not forget,i've heard several times that Gary Hardwick's record was set on old,worn abec 3 bearings,or so he says.My question is,,,more a matter of location, are we looking for a street,or a ply wood run steeper than drivable asphalt, into a street, that levels, lets say a mountain road that ends,where the asphalt equipment couldn't climb anymore:)
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bearing diameter
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On 8/28/2000
shnitzel
wrote in from
(216.66.nnn.nnn)
i'm starting to get sick of this mini miser argument.
thank you herbn for setting things a little straight. smaller balls are more than likely going to revolve more times.
however to be sure someone is going to have to sacrifice theirs, rip them a part and learn how to use a micrometer.
in the meantime let this argument stand. steel on steel has a pretty predictable co-efficient of friction. hence no matter what the size of the ball is the amount of friction will be pretty consistent.
so with this known, we can sum the advantage of the mini miser up to two traits. one being the smaller diameter.
smaller diameter means that the resistive force due to internal friction is very cloce to the axis of rotation. meaning the total friction applies less torque to the system than a bearing of larger diameter.
now the other advantage to the mini miser it the total mass of the balls is less. this means less inertia and quicker starts out of the hole (very slicgt difference. probably unnoticeable.
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Falling vs rolling
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On 8/28/2000 Herbn
wrote in from
(216.107.nnn.nnn)
There are differences but i don't even wanna get on that point,but what i'm saying is that Gary Hardwick's 62 +speed record wasn't done in bellbottom raver pants and a puffyshirt, his airodynamics were pretty damn good already ,above 99 percent of "perfect" so if you hit perfect on the same hill your not going to "crush" the record,Gary also had to be on one of the steepest hills,for instance they don't even put asphalt on 50 deg slopes and call it a road,how steep was the road Gary used?I'm sure it's a famous hill among speed boarders,you'll need a very special slope to really crush the record,lets say 70-75 mph? are you planning on going that fast?
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Bearings for Speedboards
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On 8/28/2000
Chris Chaput
wrote in from
(165.121.nnn.nnn)
Here are a few numbers and ideas to kick around. A Cherry Bomb's diameter is about 3.25". A standard bearing's balls travel on circle of diameter 20/32" (.625). A Mini Miser bearing's balls travel on circle of diameter 15/32" (.46785). This means that a Cherry Bomb rolling one complete revolution would travel about 10.21". If a ball in a standard bearing also travelled one complete revolution then it would have to go about 1.96" and a bearing in a Mini Miser would only have to travel about 1.47". At the same speed over the same lenghth road, the standard ball bearing has to travel 1/3 farther than the Mini Miser ball bearing. This means that the Mini Miser doesn't have to work as hard and should stay cooler. Less surface area smaller bearings should also reduce the friction and keep the heat down. Drakkar was right, it's not that the Mini Misers would spin fewer RPM (both bearings and the wheel would share the same), it's that each revolution provides a shorter distance for a smaller bearing. During a run where a rider was going 60mph for one mile, a Cherry Bomb would spin 6,206 revoultions (6,206 RPM). A Mini Miser would travel 9,123" and a regular bearing would travel 12,164". Mini Misers are lightweight and "quick", but don't withstand a great deal of impact. If BIGGER bearings were the answer, then the riders in the Tour de France would have their bearings closer to the tire's rim than to the hub!
Herbn,
Steepness is important to be sure, but look at skydivers, where the "steepness" is maximized. EVERYTHING has to do with aerodynamics which includes the density and temperature of the air. If aerodynamics DIDN'T play a big role at extreme speeds, then it wouldn't matter whether or not your chute opened ;)
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