28 hour drive there.......... there for 40 hours to surf............ 28 hour drive back...... mission!
Cast: Devyn Scott
Wednesday, February 9, 2011
Patagonian Expedition Race 2009: Adventure in Chile
Patagonian Expedition Race 2009: Adventure in Chile
Adventure racing athletes from all over the world experienced life changing situations whilst crossing hundreds of kilometres of wilderness. The Patagonian Expedition Race tested wills, expanded horizons and broke down barriers.Source: NEWS/Extreme_Sports/Patagonian_Expedition_Race_2009_0366.htm
Tuesday, February 8, 2011
POV - Christy Creek, OR
Video from two of the bigger drops on Christy Creek, OR.
For a trip report of our run, go here:
wheelsandwater.blogspot.com/2011/01/christy-creek-13111.html
For a write-up of our scout mission into the creek prior to running it, go here:
wheelsandwater.blogspot.com/2011/01/scout-report-rediscovering-christy.html
Cast: Nate Pfeifer
Getting Exercise on St. Thomas (Bird?s-Eye Views Are a Bonus)
If you?re looking for something more thrilling than lying on the beach, perhaps you should try the island?s newest activity: rock climbing.
Source: http://travel.nytimes.com/2008/11/09/travel/09COMrock.html?partner=rssnyt&emc=rss
ASA Big Air Triples 2010: Banasiewicz Nails 3 Double Front Flips
ASA Big Air Triples 2010: Banasiewicz Nails 3 Double Front Flips
The 15 year old Brett Banasiewicz claimed the title at the 2010 ASA Big Air Triples by successfully landing three runs with double front flips.Source: NEWS/Biking/ASA_Big_Air_Triples_2010_Augusta_Georgia_Results_0716.htm
Kitesurf - Long distance championship (10)
Yoann Grange posted a photo:
Kitesurf - Long distance championship (10)
Source: http://www.flickr.com/photos/yoanngrange/5427255472/
Crazy Wave Skiing Jaws! - SFTV S04 E16
Aniol Serrasolses hits Mexico!
Peque�o video de Aniol Serrasolses remando algunos buenos rios y cascadas en el para�so del creek, Mexico!
Here it is a little video of Aniol Serrasolses paddling some good rivers and waterfalls in the paradise of creek, Mexico!
Thanks for the support: Sweet protection, Dagger, Robson and Immersion Research,
Cast: Anyoree
Monday, February 7, 2011
Major Upsets Expected At the 2010 Horsefeathers Pleasure Jam
Major Upsets Expected At the 2010 Horsefeathers Pleasure Jam
It's that time of the year and the snowboarding community is making its way back to the Northern Hemisphere for the 2010 Horsefeathers Pleasure Jam.Source: NEWS/Snowboarding/4Star_Horsefeathers_Pleasure_Jam_2010_Austria_Preview_0806.htm
Waihi Stream First Descent 2010
For 2 years Matt Danes kept an eye on this beauty and finally one day in late 2010 the rains came. The dam was spilling and the river was at idea flow. Tyler Fox, Matt Danes and Sam Roil paddled this beauty and it was an epic day. Josh Neilson followed down the banks to capture the epic.
Enjoy it
SUP
Cast: Southern Underground Productions
6Star ONeill Evolution Switzerland
6Star ONeill Evolution Switzerland
The 6Star O'Neill Evolution wrapped up in Davos, Switzerland with Sebastien Toutant and Jamie Anderson winning the slopestyle titles and Christian Haller and Kelly Clark taking top honors in halfpipe.Source: NEWS/Snowboarding/6Star_ONeill_Evolution_Switzerland_2011_Results_0818.htm
THE CLEARWATER RIVER CANYONS
Never before seen footage brings you a glimpse of one of North America's last big volume free flowing river located in the interior of British Columbia.
The river winds some 80km from its source at Azure Lake, Squeezing through many canyons along the way - It's a big volume boaters playground in the late summer when the river drops to a navigable level for all canyons. In high water providing huge standing waves for playboaters, massive reactionals and whirlpools.
Includes footage from Gattling gorge, Donkey falls, Bailey chute and the kettle Rapids (all big class 4-5 drops)
Filmed during 3 seasons working and paddling on the clearwater river for Interior Whitewater Expeditions.
I was also lucky enough to be provided with perfect water levels in 2010 to attempt the first solo run of the clearwater at 15,000cfs from the lake down. completing the entire section in just over 7hours + 1 swim
Featured Paddlers
Sam Ewing
Mike Skagnetti
Diego Castro
Williams Hancco
Simon Wulffraat
Adrian Kiernan
Cast: Adrian Kiernan
The Wheel Deal Part 2: Wheel Size (again)
Bigger wheels are faster on rough surfaces, as I pointed out in my last post, because more of the forces that they experience as they roll over bumps pushes the wheel up rather than pushing backwards and slowing the wheel and rider down.So, why not just ride the largest wheels you can find? Unfortunately, when it comes to skateboarding and inline skating, larger wheels simply don't roll as well on smooth surfaces. The problem is that the urethane they're made of changes shape when you ride.
A simplified model of a skate wheel might look like this, where the jagged lines are meant to be springs that represent the compressible urethane. That's not to say that there are actual springs inside the wheels. It's just that the urethane acts much like springs, and it's simpler to understand the way wheels work if you pretend that they're are made of springs.As you can see in this sketch (I've exaggerated things a lot to make it easier to visualize), a wheel deforms as you ride along, resulting in a flat spot where the wheel touches the ground.
Most skate wheels are solid cylinders of material, except for the hole running through the middle where the bearings sit and the axle passes through. The springy urethane compresses when your weight pushes down on it. If you look at two wheels that are identical in shape except that one is large and the other is small, and both are made of exactly the same urethane, the larger wheel will deform more under the same weight.
This is where we can use physics to understand what's going on a little more precisely. Physicists think about springs in terms of something called the spring constant (usually symbolized with the letter k). The higher the spring constant, the more force you need to stretch or compress the spring.
If you connect two springs end to end, the total spring constant goes down (from k to k/2). In other words, it will be easier to stretch two springs connected in a row than it is to stretch just one. (You can test this yourself by tying rubber bands end to end.)As you can see in this sketch, attaching two springs side by side increases the total spring constant (from k to 2k), making them harder to stretch.If you cut a spring in half, it will double the spring constant. It's like taking the two springs connected end-to-end and getting rid of one, which doubles the spring constant from k/2 to k.
This is relevant to skate wheels because you could always make a small wheel by shaving down a big wheel. If you were to do that with the model of a wheel that I drew above, you're essentially shortening the springs. This makes the wheel stiffer (which is to say, less springy). Your weight pressing down on a small wheel will not deform the wheel as much because it's effective spring constant is much higher than it would be for a wheel that's identical in very way except for its larger size.
This makes larger wheels slower because compressing and stretching springs, or springy urethane, takes energy. With a perfect spring, you get all the energy back as it springs back to its natural shape. But no springs are perfect, and urethane is usually far from perfect.
Urethane is fairly resilient, which means that once it's deformed it bounces back into shape and gives back some of the energy that deformed it, just like stretching and releasing a spring. Depending on the exact formula of the urethane, a portion of the energy is always lost. Most of the lost energy turns into heat that warms the wheel and escapes into the air. If you squish a skate wheel you can expect to get back no more than 75% of the energy you put into it, and usually you get back a lot less. As a rough estimate, the deformation that comes with rolling on a urethane wheel will cause a large wheel to lose twice as much energy as one half its size. That's what makes larger wheels slower.
There are several ways to reduce the amount of energy lost due to the squishing of skate wheels. One common solution is to replace some of the urethane with a rigid core, like this Spitfire wheel.
Another possibility is to make the wheels wider, like these old school wheels.
Take a look at the cutaway sketch below that shows why wider wheels are less squishy. By widening the wheels, you're adding more springs (well, springy urethane anyway) in parallel. If you recall the diagram above, adding more springs side-by-side increases the total spring constant and makes it harder to stretch or compress the springs.
The wheel on the right is three times wider, and should be three times more rigid than the wheel on the left.
So, if you want bigger wheels that will roll as fast as smaller wheels, you have to make them wider. That leads to other problems. For one thing, wheels that are wide and have big diameters are heavy. That's not so good for all the ollie-based street moves, but fine for ramp, bowl and downhill skaters.
Another problem, which can be bad for all sorts of situations, is that the wider you make a wheel the harder it is to corner. If you try to ride in a circle, the outer edge of the wheel travels farther than the inner edge. Because both parts have to roll at the same speed, either the outer part of the wheel ends up turning too slowly or the inner part turns to quickly. That can lead to lots of wear and tear on the wheels, as well as extra friction that will slow you down whenever you change direction.
I've already explained why you need large wheels for riding on rough surfaces. Now you can see why smaller wheels are better for skating park concrete and obstacles. So, why not get REALLY tiny wheels for skating on smooth surfaces? Unfortunately, when wheels get too small other problems start to crop up. This post is already long enough, so I'll tell you about those issues some other time.
Source: http://feedproxy.google.com/~r/blogspot/uUCU/~3/OYiWOAttVFs/wheel-deal-part-2-wheel-size-again.html
GEAR TEST WITH MARK BRONTSEMA AND SAM WELLS, ROCK CLIMBERS; Because Climbing Is Social
Rock climbers Mark Brontsema and Sam Wells test out four climbing helmets for fit, comfort, durability and price; photos
Sunday, February 6, 2011
IMG_7567c
Mike Millard posted a photo:
The wind rises above force 4 and the kites start to move well on the flat waters of Poole Harbour
TTR Tricks - Peetu Piiroinen Snowboarding Tricks at Air & Style Innsbruck
Finlands Peetu Piiroinen's snowboarding tricks at the Innsbruck Air & Style 2011 snowboarding event in 2011. The best snowboard tricks!
LA Skate Film Festival 2010: Last Call For Submissions
LA Skate Film Festival 2010: Last Call For Submissions
Since the announcement of its debut in the city of Los Angeles back in April, The L.A. Skate Film Festival has been going through a great deal of developments that foresee a bright future for the organization.Source: NEWS/Skateboarding/Los_Angeles_Skate_Film_Festival_2010_Preview_0695.htm
Alessandra Nanni Alex Broskow Andre Englehart Andreas Trefzer
Beaver River 2010 GoPro
Just a little mashup of some footy shot on the Beaver River in Upstate NY
Cast: Dustin Farrenkopf
TRIBE WWC 2011 VIDEO ENTRY
WHITEWATER WORLD CHAMPIONSHIPS 2011
Cast: Marcos Gallegos
Indian Rock Park
This rugged 1.18 acre park, three blocks above the commerce of Solano Avenue, serves both relaxed visitors and serious mountain climbers.Source: http://www.nytimes.com/2010/09/12/us/12bcintel.html?partner=rssnyt&emc=rss
Why is Snow so Slippery?
Snow sports are a blast. I prefer snowboarding, but I would never miss out on a toboggan ride or a turn on one of those old fashioned snow saucers (What genius conceived of those anyway? Is there anything more insane that cruising down a hill on a disk with no obvious way to steer or stop? Of course, I love it anyway.) As embarrassing as it is, I've even been known to to ride an inner tube now and then.The key to all those sports - as well as skiing, snowlerblades, ski bikes, and cafeteria lunch trays - is that things slide well on snow. You could leave it at that and simply go outside to have fun, but I just had to know a bit more.
If you hunt around, you'll see that there are at least two possible reasons why snow is slippery. One common explanation is that the melting point of ice rises as you squeeze it. Water ice is unusual in that way. This could explain why ice skates work. When you stand on skates, it creates very high pressures under the sharp blades. The pressure raises the melting point of the ice until it creates a thin layer of water, which is very slippery. (This is, however, not a universally accepted explanation.)
Pressure might work for ice skaters, but it's not much help for sleds, skis, snowboards, or any other device that slides on a large, flat surface. Because your weight is distributed over a big board, the pressures are very low. At best, you might raise the melting point of the ice by a degree or so, but if the temperature of the air and snow outside is more than a few degrees below freezing, you won't actually melt any snow with pressure.
Another possibility I've heard on occasion is that the friction of the board sliding on the snow creates heat, which melts some of the snow and creates a thin lubricating layer of water. Now, this explanation sounded just absurd to me. But I didn't want to dismiss it until a estimated just how much heating you might get from snowboarding down a hill.
You know what? I was stunned -- STUNNED -- to find out that cruising down a hill creates lots of heat. At a relatively modest 36 kilometers an hour (22 mph) down an equally modest hill (imagine a 15 degree slope or so), someone about my size (75 kilograms) creates about 300 watts of heat power due to friction between the snowboard and the snow. That's three times as much power as put out by a typical light bulb. If you've ever touched a lit incandescent bulb, you know that's hot. Theoretically, friction could heat the bottom of the board by nearly 40 degrees Celsius (about 100 degrees Fahrenheit)! In the real world, the bottom of your board will never get that hot. It will only warm up to the point that it melts the snow. It takes energy to melt snow, and the melting ends up using the energy that would heat your board to any higher temperature than 0 degrees C (32 degrees Fahrenheit).
But suppose you were snowboarding on a day when temperatures went as low as at -40 degrees C, even moving slowly would generate enough heat from friction to melt the snow and provide a very thin layer of water for you to slide on. (Of course, -40 C is just about the lowest temperature ever recorded in Alaska, so you'd probably get an awful case of frostbite before you got to the top of the lift.)
So there you have it - it's friction, not pressure, that melts snow below your board and let's you whiz down the hill at a breakneck pace. Wacky.
For those of you who like the details, the math that led me to this conclusion is below.
The Math and Physics
You can change the parameters of the problem to model any sliding sport you like, but I'm using a snowboard in my analysis.
The first thing to do is figure out how much work is done when you slide on a snowboard. Work is defined as force times distance. Specifically, we're interested in the frictional force multiplied by the distance traveled.
The force of friction is just the force pushing the snowboard down onto the snow multiplied by the coefficient of friction (u).
Because the snowboard is moving downhill, the force pushing against the snow due to the mass of the snowboard and rider is reduced by the cosine of the hill slope.
Friction force = m g u cosine(theta)
m = rider's mass (I'm using 75 kilograms)
g = acceleration due to gravity (0.8 meters per second squared)
u = coefficient of friction for a waxed board sliding on snow (about 0.04, according to Wikipedia)
theta = slope of the hill (I'm using a modest 15 degrees)
If you multiply this by the distance traveled on the hill, you get the total energy expended on the trip. If instead, you multiply the force by the velocity of the snowboard, you get the work per unit time. That's the same as the power (watts in SI units).
Power = m g u cosine(theta)* v
v = velocity (for this problem, I'm using 10 meters/second, which is about 36 kph, or 22.5 mph)
Plug all that in, and you find a power output of about 284 watts to slide down the hill.
The equation for heat conduction through a slab of material (such as a snowboard deck) is
Power = dQ/dt = k A (T2-T1)/L
k = thermal conductivity (about 0.25 Watts/(meters*degrees Kelvin))
A = area of board touching the ground (about .25 square meters for a typical board)
T2 = temperature on the hot side of the board (in Kelvin)
T1 = the temperature on the cold side of the board
L = the thickness of the board (I'm using one centimeter, 0.01 meters)
When I rearrange this to solve for the temperature difference between the two sides of the board (T2-T1) and plug in the numbers, I get temperature difference of about45 degrees.
As I mentioned above, that's the maximum temperature difference between the two sides, but the hot side should never get above the freezing point of water because the heat generated by friction would have to melt all the snow before it could lead to higher temperatures. That's because of the phase transition from ice to water that occurs at the freezing point (It's the same reason that water with any ice in it at all will have a temperature of exactly 0 degrees Celsius. You can confirm this by putting a pot of snow on the stove and turning up the heat. The temperature will rise to 0 degrees C and stay there until all the snow is melted.).
So, if you're out snowboarding when the air temperature (and top of your board) are at -5 degrees Celsius, the temperature of the bottom of your board be about 0 degrees Celsius when you're moving along at 10 meters/second. In fact, it will always be at about 0 degrees Celsius if you're moving at almost any reasonable speed, and there will be a very thin layer of water under it due to all the frictional energy you're generating by sliding down the mountain.
Source: http://feedproxy.google.com/~r/blogspot/uUCU/~3/98TqO5Qa59k/why-is-snow-so-slippery.html
POV - Christy Creek, OR
Video from two of the bigger drops on Christy Creek, OR.
For a trip report of our run, go here:
wheelsandwater.blogspot.com/2011/01/christy-creek-13111.html
For a write-up of our scout mission into the creek prior to running it, go here:
wheelsandwater.blogspot.com/2011/01/scout-report-rediscovering-christy.html
Cast: Nate Pfeifer
Saturday, February 5, 2011
Tuomas Kaukola 2010
SPOTS:
FINLAND: Neitikoski, Vanhankaupunginkoski, Kattilakoski, Matkakoski, Malkakoski, Taivalkoski
NORWAY: Sj�k, Sjoa, Upper Ula,
GERMANY: M�nchen
Cast: Tuomas Kaukola
Source: http://vimeo.com/channels/whitewater#18654054
Jonathan Bergeron Jose Felix Hormaetxe Josh Clark Josh Obert
In Malibu, a Rock Scene Where Hollywood Cameras Roll
The Santa Monica Mountains, which made cameos in ?M*A*S*H,? ?Iron Man? and ?Tarzan Escapes,? offer hundreds of rock-climbing routes.Source: http://travel.nytimes.com/2009/04/10/travel/escapes/10rock.html?partner=rssnyt&emc=rss
Fall Chillout Kayaking at Soca River, Slovenia
Some guys from Team Liquidlogic Kayaks Europe had a nice chillout weekend at Soca River in Slovenia.
Thx at Liquidlogic Kayaks and Ophion Paddles for the support.
ophionpaddles.com/
Cast: Team Liquidlogic Kayaks
Source: http://vimeo.com/channels/whitewater#17684783
Jonathan Bergeron Jose Felix Hormaetxe Josh Clark Josh Obert
Friday, February 4, 2011
The Results of the 2010 Crocodile Trophy Ring D�j� Vu
The Results of the 2010 Crocodile Trophy Ring D�j� Vu
Despite severe flooding and mudslides at the 2010 Crocodile Trophy in Australia, this year's athletes endured it all. The final results of the 10 day bike race are strangely similar to the results of 2009.Source: NEWS/Biking/Crocodile_Trophy_2010_Australia_Results_0798.htm
Red Bull X-Fighters World Tour 2010: Nate Adams Defends His Title
Red Bull X-Fighters World Tour 2010: Nate Adams Defends His Title
At the grand finale of the Red Bull X-Fighters World Tour 2010 in Rome�s Stadio Flaminio, Spanish rider Dany Torres defeated American Adam Jones in a thrilling final.Source: NEWS/Biking/Red_Bull_X-Fighters_World_Tour_2010_Rome_Results_0788.htm
Winners Of Crystal Mountain Junior Freeskiing Championships
Winners Of Crystal Mountain Junior Freeskiing Championships
Sam Cohen and Camilla Loughlin take the first place wins of the male and female 15-17 year old divisions respectively. Strangely enough, the highest score of the 2010 Crystal Mountain Junior Freeskiing Championship came from the 12-15 year old boys.Source: NEWS/Freeskiing/Winners_Of_Crystal_Mountain_Junior_Freeskiing_Championships_0633.htm
2010 West Coast YSC Tour de Pink
Some of the sights -- and voices -- of the 2010 West Coast YSC Tour de Pink. Giant is proud and honored to be a sponsor of this event. The ride started on Friday, Oct 28 at Giant HQ in Newbury Park, CA -- and ended three days later at Pt. Mugu State Park near Malibu. Read more at http://www.giant-bicycles.com/en-us/news/article/west.coast.ysc.tour.de.pink.ride.finishes.at.pt.mugu.state.park/15286/
Source: http://broadbandsports.com/node/41504
Jon Murakami John Starr Jonathan Bergeron Jose Felix Hormaetxe
The Wheel Deal Part 1: Wheel Size
Many extreme sports rely on wheels of one type or another, including skateboarding, mountain boarding, inline skating, street luge, BMX and FMX. Different situations require different types of wheels, depending on the terrain and the types of riding you're doing.My favorite extreme sport is skateboarding, so this post focuses primarily on the options available in skate wheels. But the physics involved applies to any wheeled sport.
If you skate, you know that there are lots of wheels designs on the market from tiny, rock-hard wheels for street skating to giant, gummy wheels for old school cruising. Why are some wheels better for certain uses and not so good for others? As you probably guessed - it all comes down to physics.
Wheel Size
Among the many things you need to consider in choosing the best wheel for your riding is size. Most pro street skaters opt for small wheels. It's a good choice. Small wheels are fast on smooth surfaces such as skate park concrete, wood ramps, and most of the boxes, benches and banks you're likely to hit. But on asphalt or chewed up concrete, little wheels are much slower than big wheels. Just about every skater has at one time or another had the unpleasant experience of running across a pebble or crack that stops their board dead in it's path, sending the rider for a rough tumble. Those sorts of sudden stops are more likely if you ride tiny wheels.
So, what's size got to do with it? Well, here's a little sketch to show you what's going on.
The small red cirle represents a wheel with a diameter of about 50 millimeters, typical of lots of street and park wheels. The big black circle is like a large (95 millimeter) cruising wheel. This sketch shows the wheels just as they hit the edge of a 20 millimeter step (in this picture, I'm imagining the wheels rolling to the right), which is the sort of thing you might run across as you ride over the joints between sections of a typical sidewalk.The arrows show the direction of the force that results from the wheels hitting the obstacle. As you can see, the black arrow points up and to the left. That means some of the force pushes the wheel upward and some of it pushes back.
The red arrow is mostly pointed to the left and just a bit up, which means most of the force exerted by hitting the step goes into slowing the wheel, and the board it's attached to.
Of course, most of the bumps and cracks you'll run across in real life are a lot smaller than this. Even for smaller obstacles, though, more force will go into slowing a small wheel down than would go into slowing a larger wheel. You'll still get a force pushing the larger wheel upward, which makes for a rough ride, but at least it doesn't do as much to sap your speed (or stop you in your tracks).
If you race down a big hill made of asphalt, you end running over lots of little bumps that seriously slow small wheels, but aren't such a problem for big ones.
Are big wheels always better than small ones? Not at all. In fact, small wheels are usually MUCH faster than large wheels on smooth surfaces. Want to know why? Check out The Wheel Deal Part 2 in my next post to find out one reason that small wheels are better (sometimes).
Source: http://feedproxy.google.com/~r/blogspot/uUCU/~3/WRmZPn7vfuU/wheel-deal-part-1-wheel-size.html
2011 Dodge Durango at the L.A. Auto Show
2011 Dodge Durango walk around from 2010 LA Auto Show. Fred Deperez talks through the highlights of the all-new Durango live from the show floor
PopSci covers eXtreme Sports Physics in February
Popular Science magazine has another column featuring my views on some aspects of extreme sports physics. They asked me why record speeds recorded for skiers are substantially higher than record snowboard speeds. They also asked under what circumstances a snowboarder might have an advantage over a skier in a downhill race. Pick up a copy of the
They used a cropped portion of the image above in the article. It looks pretty strange in the magazine, but I like the shot showing me carving frontside at the Whitetail Resort in Pennsylvania. I normally wear a helmet and goggles, but the PopSci folks wanted to see my face.
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