Seems like they could get an extra 10% by simply going to a higher track. Mexico City is popular at 2250m of altitude..
Also less oxygen for the cyclist.
The world's fastest human-powered vehicle tops 85 mph
81–90 of 112 posts
Re: The world's fastest human-powered vehicle tops 85 mph
#82So let me get this straight, WeChat and other major companies are downloading pirated Xcode software which has malware?
A swing and a miss.
You might try again, on a different story. This doesn't seem to fit here.
Re: The world's fastest human-powered vehicle tops 85 mph
#83This is probably the few projects in life where you can say you've challenged your mind just as much as you've done your body. And one can see the impact of both of these in these young and beautiful "geeks". What a project it must be to work at - beautiful minds and beautiful bodies. And the happiness shows. :-)
Re: The world's fastest human-powered vehicle tops 85 mph
#84So my question is now: In terms of aerodynamics, what aren't they doing? Some commentators have noted that the shape of this bike is just about as good as it can get. The rider/engine is also not going to see any vast improvements. So rather than this become a pure athletic event, where can engineers look for improvements? Will they have to start dealing with boundary layer issues? Will the next generation of bike be…
The majority of the drag affecting a modern HPV racer is caused by the wheel aperture. Perfectly fitting the fairing to the tyre isn't practical, due to flex in the wheel and the tyre casing. Managing airflow around this gap is a largely unsolved problem.
Some improvements could be made by reducing the rolling resistance of the tyres or the efficiency of the drivetrain, but this will have only a relatively small impact; this drag increases linearly with speed, whereas aerodynamic drag increases geometrically.
Re: The world's fastest human-powered vehicle tops 85 mph
#85I'm a little surprised nobody has mentioned the opaque fairing, visibility, or the camera.
At first I thought it might be to keep the weight down, as there are plenty of composite materials that are lighter than (even thin) plexiglass. But then there's the weight/complexity of the camera, display, and battery.
Then I thought, well, the rider in in such an odd position, maybe he wouldn't be able to see very much even if there was a window.
But apparently the actual reason is that the rider produces so much heat that a window would fog up, and it would be too difficult/unsafe for the rider to wipe it. Given the white coloring, I suspect they're also trying to avoid cooking their human power source.
Here's part of a Q&A where they discuss visibility:
Re: The world's fastest human-powered vehicle tops 85 mph
#86So my question is now: In terms of aerodynamics, what aren't they doing? Some commentators have noted that the shape of this bike is just about as good as it can get. The rider/engine is also not going to see any vast improvements. So rather than this become a pure athletic event, where can engineers look for improvements? Will they have to start dealing with boundary layer issues? Will the next generation of bike be…
Does it have to be a bike? What about a rowing rig, where you can leverage the powerful muscles in your back and upper body?
Re: The world's fastest human-powered vehicle tops 85 mph
#87The d&d fan in me thiks falling is a free action. A human powered plane doing a dive would go faster I'd bet. Not prepared to rules lawyer that case though.
If you're willing to allow that, then just wear a single shoe (to be the 'vehicle') and do a BASE jump.
You might want to bring a parachute too.
Re: The world's fastest human-powered vehicle tops 85 mph
#88Re: The world's fastest human-powered vehicle tops 85 mph
#89So my question is now: In terms of aerodynamics, what aren't they doing? Some commentators have noted that the shape of this bike is just about as good as it can get. The rider/engine is also not going to see any vast improvements. So rather than this become a pure athletic event, where can engineers look for improvements? Will they have to start dealing with boundary layer issues? Will the next generation of bike be…
Does it have to be a bike? What about a rowing rig, where you can leverage the powerful muscles in your back and upper body?
The limit is cardiovascular, not muscular. World class rowers and cyclists have about the same power output. A rowing bike would be larger (so less aerodynamic) and difficult to engineer.
Re: The world's fastest human-powered vehicle tops 85 mph
#90Earlier quoted context omitted.
Absolutely. Being trained for such short intervals, I wonder how much their power output would drop in the final 200m after that 5 mile buildup. In any case, there has to be some optimal cyclist build for this event. I suspect it's probably somewhere between a time trialist and a pure sprinter.
Would it be within the rules to include a power capturing mechanism like a flywheel or spring that can be unleashed at the end? That would change the game to maximizing total energy output over the 5 miles, and make the whole section count.
Even without reading the rules - no. Otherwise, why not spend 8 hours to go the 5 miles, charging up the system the whole time, and get a brief burst of 100+ mph at the end? It'll end up seeing who can build the better power capturing mechanism, not seeing how fast a human powered vehicle can go.