Graeme Obree plans to shatter hpv world land speed record

He's certainly come up with an interesting design, but it must be sheer hell trying to see where you're going when lying face down. My guess is that he may come close to the record speed, but I have reservations as to whether he'll be able to beat it. Machrihanish is probably the worst place on earth to do it, though, as it's always windy there. The runway may be long and wide (it was a designated Space Shuttle diversion landing strip) but it's effectively a corridor running between hills, with the prevailing wind virtually blowing in one end.
 
An article that first got me interested in the math for HPV (1983?): "The Aerodynamics of Human Powered Land Vehicles" Gross, Albert C.; Kyle, Chester R.; Malewicki, Douglas J.
Scientific American, vol. 249, issue 6, pp. 142-152 scan:

http://www.zzipper.com/documents/HPV_Paper.pdf

Best, Joe Mc.
 
Jeremy Harris said:
He's certainly come up with an interesting design, but it must be sheer hell trying to see where you're going when lying face down.

I'd say it's just look down and follow the straight line, since there's no turns and no obstacles.
 
http://www.gizmag.com/graeme-obree-beastie/28234/

graeme-obree-beastie-1.jpg
 
I think Matt weaver had the best design. This just looks suspectible to cross winds. I assume obree figures his advantage is the ability to produce more wattage in the prone position than recumbent. Weaver's ETA edge looks the most aero.
 
Too much wet area will kill his speed. I have good confidence in the Annecy university team (France), they did 122km/h last year (absolute record is 133kmh).
RTEmagicC_reception1.jpg.jpg
 
In my book it doesn't count if someone has to give you a push and/or someone allows you to draft. I think it should be 100% independent from 0-top.

I had a friend I used to play golf with, and he didn't think it was a problem to improve his lie. In other words, he would approach the ball and move it an inch or two until it rested on a high spot in the grass. I would start counting strokes out loud each time he touched it, but it didn't phase him a bit. He'd still do it and then write a score that he liked. He didn't think it was cheating because he wasn't moving the ball closer to the hole or significantly sideways to get around an obstacle, but it's still against the rules to touch the ball (on the green is different). He also took mulligans, which I can't stand. I like to play it pure from start to finish, even if the first swipe is a gaff.

So if a couple guys push you to a balancing speed, then you have not achieved anything under your own power.

I also claim that even though the Wright Brothers invented the first practical airplane, it was still a joke that they had to use a pulley system to get it off the ground. It wasn't getting up to speed on its own power. Sure, in the soft sands of Kitty Hawk they didn't have much of an option short of building a runway, but when they demonstrated their plane five years later in Paris, they still needed their weighted pulley system to get the plane moving.
 
pretty pointless argument,
years ago, i remember reading some drama over this independent starting/stopping in the HPV racing world.
there are hpv nuts that think adding this rule would somehow legitimize hpv as a road vehicle...

anyways, its pointless...

some hpv are not pushed in any ways, they use a detachable training wheels thingamajig....


and meanwhile in the velodrome...

Womens-team-pursuit-World-Cup-Ma.jpg
 
The IHPVA has a "15 meter" rule that states they can only be pushed for 15 meters. Considering that they have to ride for 4 miles before being timed, that is a very short launch distance. Or at least that keeps it consistent...

Some speedbikes (like mine) do have a landing gear that allows them to be started / stopped without assistance. It is still a far cry from a "practical vehicle".

-Warren.
 
veloman said:
I think Matt weaver had the best design. This just looks suspectible to cross winds. I assume obree figures his advantage is the ability to produce more wattage in the prone position than recumbent. Weaver's ETA edge looks the most aero.

Maybe Obree doesn't want to grow the obligatory recumbent beard.
 
http://www.dailyrecord.co.uk/sport/other-sports/cycling/graeme-obree-puts-beastie-up-2272927

Obree said: “The last week has been a bit stressful. The Beastie has been 20mph off her pace and I’ve spoken to competitors with backgrounds in aerodynamics about why it hasn’t gone quicker.

“Everyone has been too polite to tell me the shape’s a piece of s***. Eventually, they let on.

“The mechanics of the bike are good but there are problems with the skin casing and the way the air flows over it.

“The experience has taught me humility. I tried my best with my knowledge of physics and even some of the best engineers in the world can’t explain sometimes why one machine goes like the wind and another like a donkey.
 
veloman said:
Could these streamliners be some of the most aerodynamic shapes in the world? At least in the practical world. What about missles? No wheels to disturb airflow.

They're close to being the most aerodynamic two-wheeled human vehicles available. I think some more aero mods, like dimpling and possibly other surface features, could boost the energy efficiency on the order of 10-30%.
 
Chalo said:
veloman said:
I think Matt weaver had the best design. This just looks suspectible to cross winds. I assume obree figures his advantage is the ability to produce more wattage in the prone position than recumbent. Weaver's ETA edge looks the most aero.

Maybe Obree doesn't want to grow the obligatory recumbent beard.

Lol, so the unix/linux system admins and recumbent guys grow beards.

Do they have something in common? Maybe it's that they're both over-represented in Portland, lol.

Or, it could be that they're both the most intelligent people in their respective fields.
 
sk8norcal said:
http://www.dailyrecord.co.uk/sport/other-sports/cycling/graeme-obree-puts-beastie-up-2272927

Obree said: “The last week has been a bit stressful. The Beastie has been 20mph off her pace and I’ve spoken to competitors with backgrounds in aerodynamics about why it hasn’t gone quicker.

“Everyone has been too polite to tell me the shape’s a piece of s***. Eventually, they let on.

“The mechanics of the bike are good but there are problems with the skin casing and the way the air flows over it.

“The experience has taught me humility. I tried my best with my knowledge of physics and even some of the best engineers in the world can’t explain sometimes why one machine goes like the wind and another like a donkey.

Poor guy. Lessons learned. But yeah, you don't go talking 100mph when the best in the world who have been doing it for years are at 83mph on their very best days.

I think his design is just uber scary in the slightest cross wind.
 
Chalo said:
veloman said:
I think Matt weaver had the best design. This just looks suspectible to cross winds. I assume obree figures his advantage is the ability to produce more wattage in the prone position than recumbent. Weaver's ETA edge looks the most aero.

Maybe Obree doesn't want to grow the obligatory recumbent beard.


I had lunch with Matt Weaver a couple weeks ago, and my friend Gabe who helped make various streamliner bodies used in HPV speed challenges years ago.

All of us were beard equipped, and thus a recumbent would be capable of doing our bidding. :)
 
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