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I'm trying to make a non-rocket-propelled motorbike that has a top speed of at least 1050 kph. (Presumably on flat ground...)

You don't have to worry about the rider, or steering, too much...

What makes the Dragon Rider so unique is the fact that it was a powered suit that included a bike; without the suit no rider would ever be able to grip or endure riding it.

And its controlled by a brain-computer interface, that's intended to take care of steering...

If your design can do these other things, it'd be better, but its not required...:

  1. Is able to travel on flat snow at over 1000 kph
  2. Climb cliffs with a slope of 70 degrees at over 300 kph.

I think the main difficulty with actual physics would be the compact, high-energy power source that the bike would need, but it could be finding a material strong enough to handle the forces involved...


Basically, since its apparently impossible for a HsSSV-01 (Dragon Rider) to be made with parts manufactured with modern materials and tech, what are the specs of the (sci-fi / future) components I'd need to make one?

It should look something like this:

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This question asks for hard science. All answers to this question should be backed up by equations, empirical evidence, scientific papers, other citations, etc. Answers that do not satisfy this requirement might be removed. See the tag description for more information.

closed as off-topic by a CVn Aug 5 '15 at 14:21

  • This question does not appear to be about worldbuilding, within the scope defined in the help center.
If this question can be reworded to fit the rules in the help center, please edit the question.

  • $\begingroup$ @PavelJanicek - Clarified / Changed, "What (sci-fi / future) stuff do I need to make my Dragon Rider?" $\endgroup$ – Malady Aug 4 '15 at 11:28
  • $\begingroup$ If this was on Writers I would recommend you using Unobtainium ;) $\endgroup$ – Pavel Janicek Aug 4 '15 at 11:28
  • $\begingroup$ Is this motor only supposed to travel in a straight line? It's going to be much harder to build if it also needs to navigate and even more if it has a rider that needs to survive doing so. $\endgroup$ – Erik Aug 4 '15 at 12:09
  • $\begingroup$ @Erik - Umm... No, it's gotta turn and stuff, but its actually "a powered suit that included a bike; without the suit no rider would ever be able to grip or endure riding it. " (From the Dragon Rider Article...) $\endgroup$ – Malady Aug 4 '15 at 12:11
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    $\begingroup$ @Erik, hmm, I don't think it's that bad actually. I mean it's not like supersonic fighter jets don't turn. Your turning circle will just have to be pretty large to not have the rider black out doing them. Back-of-the-envelope sums says you need a bit over 10secs to do a 90 degree turn at 1000 kph. $\endgroup$ – Fhnuzoag Aug 4 '15 at 15:59
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The fastest motorcycles don't really look like motorcycles at all, but more like missiles riding along the ground on two wheels. Even the engine powered LSR cars look a lot like that, for very good physics reasons.

At high speed, most of the force opposing you is air drag, which goes up as a square of the velocity. Since your vehicle is going to be moving just under the speed of sound at sea level, you will also be getting a lot of "wave drag" as well from the transonic flow (possibly some regions of supersonic airflow over parts of the vehicle as well).

So low frontal area is key (hence the missile shape), and the vehicle will also need to be made of strong but lightweight materials to deal with the forces on the vehicle, and have some clever aerodynamics to remain on the ground and under control at that speed. Air friction will also be an issue as well, so heat resistant materials are a must, and the interior of the vehicle will need a way to shield or reject the heat from the cockpit, and some clever engineering to ensure the waste heat from the engine(s) will also be able to be rejected.

Calculating the power required will need a lot more information (size, weight, acceleration, how far you have to travel at that speed), but engine powered LSR vehicles need a lot of horsepower (in the 1930's, it was common to use one or more 12 cylinder aircraft engines to power the cars to "just" 400mph (640kph), and one trick used then was to have the engines dump their heat into tanks filled with ice: using heat sinks rather than radiators, and dump the boiling water out at the end of the flying mile course and refill with ice at the other end). Most modern LSR's use multiple highly modified V-8 engines with forced induction (turbo or superchargers), as well as exotic fuel mixtures and power boosting tricks like water injection or nitrous oxide injection.

Your other requirements will be very difficult, if not impossible to do with the same vehicle. The traction requirements for an over snow vehicle are much different, and since snow is a loose, low friction substance, getting enough traction from the drive track will be difficult. LSR vehicles typically ride with minimal ground clearance to minimize some of the aerodynamic effects, and also have limited suspension travel and turning locks (you need to be pointed very accurately not only to hit the speed traps but also to prevent the aerodynamic forces from flipping the vehicle or turning you into a cloud of confetti), so cross country movement, hill climbing etc is out.

If you really need to go that fast, maybe you should consider an airplane...

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  • $\begingroup$ Hmm... Should I request a move to Engineering.SE or Physics.SE? Then again, I guess you wouldn't be the one to ask? $\endgroup$ – Malady Aug 4 '15 at 13:49
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    $\begingroup$ It depends on what you are trying to achieve. If this is a hard science question or you really want to build an LSR bike, then Engineering may be the best place to ask. For world building, this gives you the idea of the "arcs" you should work within, if you don't want this to be fantasy. $\endgroup$ – Thucydides Aug 4 '15 at 13:58
  • $\begingroup$ Thank you, I do want a more numerical answer... So, I'll request a move to Engineering... $\endgroup$ – Malady Aug 4 '15 at 14:20
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According to wikipedia the fastest landmoving motorcycle with no rockets moves at about 605 kmph.

So you are not that far from the target. I think the problem here is that when you try to move any faster than this, the motorcycle have problems getting grips of the tires because of lack of downforce, and the weight is too low.

To make the motorcycle move faster you would need to improve the motor. Remember that the faster you want to go the force needed is almost exponentially increasing. So you need a lot more (down)force, a lot more power, and then you need more power to compensate for the breaking force the downforce is making.

I don't think this is just a question about changing the materials of the motorcycle i think one would need to rethink the motorcycle, more effective motor , more downforce and more traction.

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  • $\begingroup$ Well, when I said "Materials", I didn't just mean... 'materials'... I meant... Err... 'Parts'? ... I was/am looking for an answer with things like: "You need an engine that can output X Joules", and "Your wheels need Y friction-coefficient..." and things like that... ... Do you know a word that is better than 'materials'? $\endgroup$ – Malady Aug 4 '15 at 12:08
  • $\begingroup$ @Malandy Maybe "components?" $\endgroup$ – Frostfyre Aug 4 '15 at 12:38
  • $\begingroup$ @Frostfyre - There... If you want, you can edit it too, of course... $\endgroup$ – Malady Aug 4 '15 at 12:54

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