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Getting Delay, without using any effects...

How To Do A Hoverslam - Kerbal Space Program Doesn't Teach

Payback says...

Haven't viewed the video yet, but just common sense tells me no propulsion system is 100% efficient, so the losses over time will be larger, and less efficient in overall fuel use.

It's like the most efficient way to drive a hybrid is to floor the accelerator to get to speed, then try to go as fast as possible, using as little accelerator pedal as possible.

Conversely, the rocket would just be wasting fuel trying to slow down before it had to full burn to stop in time.

I'm just impressed they keep the terminal velocity down enough they don't need to use drogue chute(s).

Armadillo Cargo Bike With Hydrogen Fuel Cell, 300 km range

newtboy says...

Have you ever ridden a 10+ speed or mountain bike for hours on end? Recumbent bikes are far more comfortable, and can facilitate greater pedal power because you have something to push against.
I couldn't figure out why there's no cockpit or fairing. That seems like a design flaw to me....or a planned upgrade at extra cost.

mxxcon said:

if it's such a bulky machine, why not make it regular bike sitting position with an encloded cockpit? Better visibility and warmer in cold Swedish winters.

Russian parents made you learn Piano? Improvise!

Phooz says...

That dog knows how to steal a show!

Also the piano run through effects pedals, a guitar amp, and that controller he has is pretty righteous! I want to hear what it sounds like with some Beethoven or any classical music!

Russian rock cover band kills it with Chicago's 25-or-6-to-4

Ginrummy33 says...

I was wondering if the guitar guy was gonna do the whole Wah pedal thing but yes, he did. Awesome cover, nothing different or new, but if you like nearly 100% reproductions this is a great one.

4 Revolutionary Riddles

newtboy says...

3) it moves backwards because the force is applied to the entire system/bicycle. The wheel going backwards turns the gears and chain, rotating the pedal 'forwards' (rotating it in reverse). Because the wheel is much larger it travels much farther back than the pedal rotates forwards, even with 1:1 gearing the pedal actually travels backwards slightly compared to the ground, but in higher gears it gets much easier.
It's because the tire is so much larger than the crank, that makes it easier to rotate the tire than the crank even at 1:1, so it goes backwards.
It's counter intuitive, but I actually checked my work and yep, my bike went backwards in all gears....no sliding needed. Try it.

visionep said:

I guess the hint for these is the rotational test that they show at the first.

1) A sticky object that would let go like a wall crawler that climbs down a wall would create this effect. (see below)
2) You can't. As you approach infinite speed it would get very close. (see below)
3) The bike will move forward. (see below)
4) The outside parts of the wheels that overlap the rail. Also if the train has a flywheel that is larger than the wheel size the bottom of the flywheel would also always move backwards faster than the train was moving.

1) He says "what object is inside?" so I'm not sure a liquid would count. Also a viscous liquid would flow a slow rate and would probably not stop and start. You might be able to get a viscous liquid to stop and start if you had fins, but that still might just move slowly or gain enough momentum to roll fast without any flow.

2) A little excel calculation shows that the average velocity approaches twice the initial but will never hit it.

attempted m/s - total time - average m/s
1 100 1
2 50 1.333333333
3 33.33333333 1.5
...
200 0.5 1.990049751
201 0.497512438 1.99009901

3) I'm not sure if the parameters of this experiment are explained sufficiently.

If it is allowed to slip then no matter the mechanical advantage a hard pull should always be able to get the bike to skid back and defeat friction.

If the bike is not allowed to slip on the ground then I don't understand how it could ever move backwards, the only options would be that it doesn't move at all or it moves forward.

If it can't slip then the ratio of the pedal to the wheel is what is in question. Bikes only have gear ratios higher than 1 and the crank is smaller than the tire so the tire will always rotate more than the crank thus the bike should move forward.

4 Revolutionary Riddles

visionep says...

I guess the hint for these is the rotational test that they show at the first.

1) A sticky object that would let go like a wall crawler that climbs down a wall would create this effect. (see below)
2) You can't. As you approach infinite speed it would get very close. (see below)
3) The bike will move forward. (see below)
4) The outside parts of the wheels that overlap the rail. Also if the train has a flywheel that is larger than the wheel size the bottom of the flywheel would also always move backwards faster than the train was moving.

1) He says "what object is inside?" so I'm not sure a liquid would count. Also a viscous liquid would flow a slow rate and would probably not stop and start. You might be able to get a viscous liquid to stop and start if you had fins, but that still might just move slowly or gain enough momentum to roll fast without any flow.

2) A little excel calculation shows that the average velocity approaches twice the initial but will never hit it.

attempted m/s - total time - average m/s
1 100 1
2 50 1.333333333
3 33.33333333 1.5
...
200 0.5 1.990049751
201 0.497512438 1.99009901

3) I'm not sure if the parameters of this experiment are explained sufficiently.

If it is allowed to slip then no matter the mechanical advantage a hard pull should always be able to get the bike to skid back and defeat friction.

If the bike is not allowed to slip on the ground then I don't understand how it could ever move backwards, the only options would be that it doesn't move at all or it moves forward.

If it can't slip then the ratio of the pedal to the wheel is what is in question. Bikes only have gear ratios higher than 1 and the crank is smaller than the tire so the tire will always rotate more than the crank thus the bike should move forward.

4 Revolutionary Riddles

newtboy says...

1) < 1/2 full of honey or other slime
2) bike will go backwards 1/4 pedal turn (forcing the pedal to rotate forward but move backwards) regardless of gearing because the wheel rotation/travel is much longer than the pedal rotation/travel

3) (T1+T2)/2 can never equal or be less than (T1)/2...so impossible unless you can finish lap 2 before you start it

4) a small portion of the lip of the wheels, farther out than the part that rides on the rail

Side note, how did you all get the numbers mixed up? #2 is the bike, not the track.

4 Revolutionary Riddles

coolhund says...

1) Honey or similar liquid
2) Three times as fast.
3) Nowhere. If you pull hard, the wheel will spin, until the pedal is horizontal, then the bike will still not move (the back wheel will not turn).
4) Lower half of the wheels.

Cyclist Uses Aerodynamics Over Leg Strength

newtboy says...

When I rode 30+ miles a day, almost 30 years ago, I used to do something similar on downhills. I wouldn't take the toe clips off, but I would hang my ass over the rear wheel with the seat in my gut. This flattened my body and made me more aerodynamic (but not nearly as much as he is) and put my weight farther back and lower, meaning I could brake much harder without going over the front. His center of gravity probably goes higher in this position with his legs that high. Since my feet never left the pedals, I could still pedal if needed and get back upright in an instant.

I never raced, so I don't know if this would have been against any specific rules, but taking your feet off the pedals that way would make you far less stable, imagine if he had to brake or swerve, and reattaching at speed is no walk in the park either, so it's probably considered a likely hazard to others and banned...but that is just a guess.

Fairbs said:

do you know the rationale with banning? Potential danger to other riders? It's interesting to me that it would be banned. Kind of like the first guy that went over backwards on the high jump, it seems like a legit innovation.

Cyclist Uses Aerodynamics Over Leg Strength

Khufu says...

It's not a competition, they have no numbers. It's a training ride. you would never use a fixed gear bike in a road race. But they are great training tools to get a very even pedal cadence.

spawnflagger said:

Not sure what competition this is, but that technique is certainly against the rules in Tour De France, as well as many other cycling competitions.

Cyclist Uses Aerodynamics Over Leg Strength

Khufu says...

I don't see a motor... there is no derailleur because he is riding a fixed-gear bike. you can also tell from the way the back wheel meets the frame (axle hole has wheel insert from back and is tightened to desired chain tension).

He probably avoids pedaling down fast decents for this very reason. rpm gets so high it no longer helps to pedal. I see people on fixies riding up and down mountains in my area, the real impressive part is how they climb UP the mountain in such a big gear.

song77 said:

Motorized, no derailed, and he had to slow the bike down to put his cleats back in . Made skillz in planking thou i wouldn't have the guts to do that

Not sure if this family needs another child...

newtboy says...

You fuckers, it's called a brake pedal. I just love how her only concern is for the trucks underside, not that her baby daddy apparently just killed someone's *pet in front of their kids without pause, or at best just intentionally ran over someone's dead (or just injured) pet.
Great parenting.
Looks a bit faked in my hyper suspicious eyes, and either way it's horrible all around.

Vroom goes the overly enthusiastic first timer

ALWAYS Set Your Parking Brake

newtboy says...

Kind of. When I installed the roll cage I had to pull the pedal out, and I never built the hand lever I intended. It's never been a problem. I don't have a clutch switch either, and 7.5-1 first gear, so I can start in gear if I have to, even on a hill.

Payback said:

No parking brake? By choice?



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