Wired thinks so.
Fun read for aero and physics geeks:
http://www.wired.com/wiredscience/2012/09/can-a-human-powered-bike-go-100-mph/
But Lance says “It’s not about the bike”.
(this ties the record for quickest Lance hijack).
I wish him the best of luck in his endeavor, but cycling in the prone is difficult IMO compared to a standard recumbent position… I’ve seen a few university ASME Human Powered Vehicle (HPV) competition bikes attempt a similar setup, and it generally turns out poorly. Of course, Obree is known for unorthodox bike setups, so if anyone can pull it off it’d be him.
Not sure why but it made me happy when I saw that it was Graham Obree trying to do this. I hope he uses some washing machine parts.
Man. If you think 80 degree STA is steep, try 180.
I wish him the best of luck in his endeavor, but cycling in the prone is difficult IMO compared to a standard recumbent position… I’ve seen a few university ASME Human Powered Vehicle (HPV) competition bikes attempt a similar setup, and it generally turns out poorly. Of course, Obree is known for unorthodox bike setups, so if anyone can pull it off it’d be him.
Is it just a biomechanical reason? Is the position just too un-physiologic to generate enough power? Or is it too unstable?
I thought I saw something once where a bike was following a car that had a windshield in front of the bike…but, I’m assuming the article says something about no help and human power only (sorry, I didn’t read it). I figure if wind resistance is taken away, it could be done with some crazy gearing on an extremely smooth road. don’t know how smooth salt flats are for bikes?
If I recall correctly (and I may be entirely mistaken) a couple of Dutch cyclists did it in a back-to-back fully-faired recumbent tandem…
as a former member of a university ASME Human powered vehicle team, i can tell you most vehicles generally turn out poorly regardless of the setup.
Trek KVF 2.5:1 airfoil present in the Aeolus D3 5 generate propulsion from 7.5º yaw and peaks around 17.5º yaw. I don’t know how much this behaviour will be affected by the increment of the Reynolds number from 30mph to 100mph but if it’s not modified it would be a matter of finding the right wind conditions (and adding some lateral wheels to improve stability because reaching 7.5º yaw at 100mph needs a serious sidewind)
I thought I saw something once where a bike was following a car that had a windshield in front of the bike…but, I’m assuming the article says something about no help and human power only (sorry, I didn’t read it). I figure if wind resistance is taken away, it could be done with some crazy gearing on an extremely smooth road. don’t know how smooth salt flats are for bikes?
For cycling while drafting, the land speed bicycle record is 166.9 mph. And, yeah, the gearing was crazy. But that’s been done.
(edit: updated speed)
Don’t understand the question. Google Fred Rompelberg, he’s gone 150mph already on a human powered bike. Yes, he was drafting off a race car.
I wasn’t asking a question, but, you’re right, my info is old. The current motor-paced flat surface record is 166.9 mph. wow!
Did I miss something in there or is he ignoring drive train efficiency and CRr ? While obviously aero drag is the big problem the other parasites aren’t negligible… That said it would be awesome to see a non-motor-drafted 100mph+ run
Is it just a biomechanical reason? Is the position just too un-physiologic to generate enough power? Or is it too unstable?
I’m not 100% sure, but I think one of the bigger reasons is that the extremely open hip angle or a makes it harder to produce power. (Of course, the aero advantages on some bikes totally outweigh that).
I’m not sure how much of that is due to training though. After riding a recumbent for a couple of years, I felt like my legs were strong enough to push my aerobic system hard. But if I haven’t been riding it much for a while, my legs are too weak and become the bottleneck.
It might be different for a sprint type event though.
Trek KVF 2.5:1 airfoil present in the Aeolus D3 5 generate propulsion from 7.5º yaw and peaks around 17.5º yaw. I don’t know how much this behaviour will be affected by the increment of the Reynolds number from 30mph to 100mph but if it’s not modified it would be a matter of finding the right wind conditions (and adding some lateral wheels to improve stability because reaching 7.5º yaw at 100mph needs a serious sidewind)
Thats a negative Roger. To set the speed record you need the average of 2 runs, run in opposite directions, with a set rest time. Unless your 60mph wind changes directions, its nor gonna work.
The other thing is that the record is 82 mph and the bike was pretty well engineered. That leaves mostly power to go from 82 to 100. I’d wager that Obree can or could put out more power than Whittington, but not by nearly enough.
And since yaw angle changes with the speed of the bike too, you’d need quite a bit of control over the weather to maintain the perfect yaw angle.
The speed is set, 100mph. I don’t have a yaw calculator handy but 100mph landspeed and needing a 16 degree yaw. I’m thinking you could have control over the needed wind by using a jet engine mounted on a car next to the bike. Hope the fairing isn’t flammable.
Trek KVF 2.5:1 airfoil present in the Aeolus D3 5 generate propulsion from 7.5º yaw and peaks around 17.5º yaw. I don’t know how much this behaviour will be affected by the increment of the Reynolds number from 30mph to 100mph but if it’s not modified it would be a matter of finding the right wind conditions (and adding some lateral wheels to improve stability because reaching 7.5º yaw at 100mph needs a serious sidewind)
**Thats a negative Roger. To set the speed record you need the average of 2 runs, run in opposite directions, with a set rest time. Unless your 60mph wind changes directions, its nor gonna work. **
The other thing is that the record is 82 mph and the bike was pretty well engineered. That leaves mostly power to go from 82 to 100. I’d wager that Obree can or could put out more power than Whittington, but not by nearly enough.
Nah. At 100 mph ground speed, a 90 degree, 21 mph crosswind will give you a 12 degree apparent wind yaw angle for the run in both directions.
But the speed is only set once you’re there. While you’re accelerating (and need the most help), the magical yaw angle would be a moving target, wouldn’t it?