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The world's fastest human-powered vehicle tops 85 mph

engadget.com

31–40 of 112 posts

Re: The world's fastest human-powered vehicle tops 85 mph

#31

Typical Canadians. Their country's flag is smaller than the GMC logo. I hope someone from UofT alumni relations gives them a call. If you are going for a speed record, you need something more like this: http://cdn.rsvlts.com/wp-content/uploads/2014/02/olympics-sk...

As a Canadian, I can relate, but I'm still amazed by all the flags I see when I come down the border!

Re: The world's fastest human-powered vehicle tops 85 mph

#32

Earlier quoted context omitted.

This isn't horribly safe, either. Wiping out at 85 MPH would suck . I'm curious what multi-cyclist vehicles could do, now that you suggest it. With the lightness of these vehicles, at what point would you have to add spoilers?

While I know it would suck to wipe out, I'm hoping with this thing it may be more of a "slide for 1000ft and off the flat road" type of suck than a "life altering injury" type of suck.

The video shows a wipeout around 4:30, just a long slide. The bike wasn't near 85mph though.

Sadly, the video is pretty cheesy and content-free. It's hard to recommend.

Re: The world's fastest human-powered vehicle tops 85 mph

#33

So 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…

I found out they have great Q&A videos on their YouTube channel. They answer here why golf ball dimples are unnecessary for a fin-like shape. https://www.youtube.com/watch?v=ZXpZy_A7mMk

Re: The world's fastest human-powered vehicle tops 85 mph

#34
post #33

So 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…

I found out they have great Q&A videos on their YouTube channel. They answer here why golf ball dimples are unnecessary for a fin-like shape. https://www.youtube.com/watch?v=ZXpZy_A7mMk

Golfball-like dimples are only half my question. In aircraft much work has been done on reducing boundary layer issues with suction holes that actively remove turbulent air. Some aircraft engines, the SR-71's in particular, do this to ensure 'clean' intake air.

Subsonic: http://www.dtic.mil/dtic/tr/fulltext/u2/274329.pdf

Supersonic: http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/2006002...

Re: The world's fastest human-powered vehicle tops 85 mph

#35

Typical Canadians. Their country's flag is smaller than the GMC logo. I hope someone from UofT alumni relations gives them a call. If you are going for a speed record, you need something more like this: http://cdn.rsvlts.com/wp-content/uploads/2014/02/olympics-sk...

I am a proud Canadian who lives in the USA and have a little Canadian sticker on my car. It's my little shout out to other Canadians on the road. I guess we're quietly showing our pride to others. Being loud about it is not in our nature. But I do like that luge helmet :)

Re: The world's fastest human-powered vehicle tops 85 mph

#36

Typical Canadians. Their country's flag is smaller than the GMC logo. I hope someone from UofT alumni relations gives them a call. If you are going for a speed record, you need something more like this: http://cdn.rsvlts.com/wp-content/uploads/2014/02/olympics-sk...

I am a proud Canadian who lives in the USA and have a little Canadian sticker on my car. It's my little shout out to other Canadians on the road. I guess we're quietly showing our pride to others. Being loud about it is not in our nature. But I do like that luge helmet :)

It's not luge. When the idiot goes head-first they call it skeleton.

Re: The world's fastest human-powered vehicle tops 85 mph

#37

So 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…

Maybe the road surface? I'm assuming an actual highway has some friction that could be sacrificed perhaps? Not sure what the cutoff is there before too little traction becomes problematic?

Just spitballing here, I have no idea how most of this stuff works.

Re: The world's fastest human-powered vehicle tops 85 mph

#38
post #33

Earlier quoted context omitted.

I found out they have great Q&A videos on their YouTube channel. They answer here why golf ball dimples are unnecessary for a fin-like shape. https://www.youtube.com/watch?v=ZXpZy_A7mMk

Golfball-like dimples are only half my question. In aircraft much work has been done on reducing boundary layer issues with suction holes that actively remove turbulent air. Some aircraft engines, the SR-71's in particular, do this to ensure 'clean' intake air. Subsonic: http://www.dtic.mil/dtic/tr/fulltext/u2/274329.pdf Supersonic: http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/2006002...

Speaking of the SR-71, you guys should all read the heavily reposted stories about it. It's such an amazing plane. While it's not flying in the sky anymore, it deserves to fly in our imagination every time somebody speaks about it.

http://oppositelock.kinja.com/favorite-sr-71-story-107912704...

Re: The world's fastest human-powered vehicle tops 85 mph

#39

Earlier quoted context omitted.

I am a proud Canadian who lives in the USA and have a little Canadian sticker on my car. It's my little shout out to other Canadians on the road. I guess we're quietly showing our pride to others. Being loud about it is not in our nature. But I do like that luge helmet :)

It's not luge. When the idiot goes head-first they call it skeleton.

Thanks - I never noticed the difference.

Re: The world's fastest human-powered vehicle tops 85 mph

#40

Earlier quoted context omitted.

Would the multiplied power be offset by the multiplied weight and potential loss of aerodynamics?

Max speed has very little to do with weight as long as you have sufficient room to accelerate. Additional drag would be small if you put one rider in front of the other and both inside of a fairing. The frontal area and shape could stay the same. This is the major source of drag. There would be small amounts of additional drag from the air running along a longer fairing, but doubling the power would more than make up…

Drag is approximately proportional to the square of the velocity, not cube.
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