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134.5 kg Concrete Bike [video] (youtube.com)
282 points by zdw on Aug 31, 2022 | hide | past | favorite | 167 comments



This reminds me of my own wacky idea for a line of fitness products: ordinary everyday items that are normal in every way except that they are intentionally designed to be physically challenging to use.

For example, doors that require a lot of force to open, keyboards with 1lb resistance springs, remote controls that weigh several kilograms, etc. Since many people have trouble going to the gym, it would be a way to introduce weight training in a way that was both unobtrusive and unavoidable.

Just one of those things that has been bouncing around in my head for years now. I think riding this bike would definitely qualify as weight training :)


This is similar to my business plan where I start a combo moving company / personal training service and charge people to move other people's furniture. Double profit!


Its not quite the same but one of the Moving Companies around boston has a rowing club.

https://www.gentlegiantrowing.org/sponsor

"and approach to moving as a sport, requiring dedication and teamwork. Many Gentle Giant employees are current or former athletes from a wide variety of sports and competitive backgrounds. Current and former employees include both Olympic, collegiate and club rowers."


Gentle Giant is really more of a rowing club that has a moving company. They moved our company a few years back and I've never seen anyone carry as much weight as quickly and effortlessly as those guys.



I watched this episode just last night. Incredible

He's got a new show out: https://www.imdb.com/title/tt10802170/


Hah, so I guess I'm not the only one with that idea then.


Have you heard of Good Gym in the UK?

https://www.goodgym.org/


What a fun idea!


Nathan Fielder already tried it. Like all of his business ideas, it was wildly successful.


Well he did go to a great school and get great grades.


We think alike! I would have started that company years ago if not for the threat of the inevitable lawsuit when a client drops a grand piano on someone’s head.


Jack Garbarino beat you to it. Read The Movement; there's a copy on my shelf.


It reminds me of "u-pick" farms. Less labor, higher prices. The only constraint is that they have to be somewhere easy to reach.


> higher prices

In my experience, I have found that the u-pick places around me are significantly cheaper than in-store or farmers’ markets. Even to the point that I don’t see how they could be profitable.


Except that moving boxes and furniture doesnt promote fitness. Most of your time will be sitting in a truck. Then it will be repetitive motions with moderate weights. It would be more akin to life as a fedex driver than a modern workout.


I've definitely seen deliveroo cyclists doing it for the fitness.


Such scheme is somewhat popular in agriculture where city dwellers come to work on a farm and are paying for the experience.


I come from an ag background, and when crossfit started getting big we joked about charging people to work around the ranch. Not surprised to hear it's a real thing. No doubt, though, that ag work can be physically demanding.


Moving furniture isn't what one would call "healthy exercise".


I have the same plan! We can team up!


Holy .. I wanted to do just that.


You're thinking too small, friend.

Build a space station with gravity via rotation. Then spin it up to 150% of normal gravity. Now everything is 50% heavier, yourself included!


You don't even need to be in space if you want to make things heavier. As always the great David Jones (Daedalus) had this idea first in his New Scientist column (16th Feb 1968), and it's included in the compendium "The inventions of Daedalus"


The idea is much older for example 1948: https://en.wikipedia.org/wiki/Rotor_(ride)

Various test chambers for astronauts where built to test how people respond to higher gravity / a rotating reference frame. Actually trying to do this runs into some unexpected issues in practice. Here is a Tom Scott video about a more recent example: https://youtu.be/bJ_seXo-Enc


The Daedalus column is specifically applying the idea to weight loss & fitness though :)


That was one of the basic questions being looked into for long duration missions.

One idea was to use higher gravity areas to reduce the need to devote time to exercise on Mars or in space etc.


Is this available to read online? Alternatively, could you summarize the idea?


I had a quick look last night on my phone and couldn't find a copy online (though I know I've had some success in the past). I'll try again later on the laptop and failing that drop you an email with the relevant page when I get a moment to scan it.


Strong Goku vibe.


I wish that VC wasted money on you instead of the same boring mobility startups.


You are thinking much too small, friend. Spin the earth faster and we can finally get rid of leap seconds.


That would defeat the initial purpose as faster Earth rotation would also make us lighter.


It's much easier to get married, so you'll have the weekly task of going to the store by foot and bring back bagfuls of groceries, and possibly two packs of bottled water... then return there because you forgot two bags of cat's litter:)

More seriously, ages ago I wondered about a way to generate power by making sort of a (very compact) exoskeleton-like contraption for each limb articulation, so walking or using arms would activate some generators. Mechanical construction would be quite a challenge, however if built in a very compact wearable way it could become a thing: sensors for body parameters could self power, the phone in a pocket equipped with a inductive charger would charge while running, etc.


> so you'll have the weekly task of going to the store by foot and bring back bagfuls of groceries, and possibly two packs of bottled water... then return there because you forgot two bags of cat's litter:)

it's the "by foot" part where this may not work as you intended.


I once met a guy on a bike ride who trained with a kids trailer loaded down with bricks. He claimed that it was more time-efficient way to train, and on race days, his bike felt like it was made of helium. My only concerns are wear&tear on knees, and the risk of a crash, getting smashed by a 200lb trailer doesn't sound fun.


The Airhub resistance trainer is a safer option. It can selectively apply magnetic resistance (drag) in order to make training rides harder. But when switched off the bike rides like normal, and there are no extra safety risks.

https://airhub.com.au/

Wear on the knees is more an issue of proper bike fit and pedaling technique. If you want to get fit as a cyclist then you have to put in some high wattage training rides. Whether the resistance comes from a heavy trailer or a steep hill or whatever makes no difference to the knee injury risk.


I know a similar story retold by yellow-jacket wearing cofee drinkers of a man who trains on a heavy mountain bike weighed down with offroad equipment and spares. The humm of his fat mountain bike tyres on the road approaching inspires ire and jelousy.

He wins the local triathlons quite regularly.


It would be a cosmic irony, since humans have been trying to make things "easier" since at least 4000 years.

I have another idea, make a lot of crank generators so that biochemical energy gets converted into electricity. I know you won't power your kettle nor your telsa but considering people 1) pay for exercise [0] 2) pay to power the devices to exercise .. I think it's due time.

[0] gym club managed to market gravity (and social context, but mostly gravity).


> keyboards with 1lb resistance springs

This may be a good recipe for tendinitis.


Everything here sounds like a recipe for injury. When you're lifting heavy things you should be focused on (correctly) lifting the heavy thing. If you turn the oven door into a deadlift you're going to forget one day and throw out your back.


After three days of the 4kg remote you’ll be over at your date’s house and promptly punch her in the face when picking up her remote.


Have you heard of crossfit?



For some reason the feeling of getting exhausted on an ultralight racing bike feels much easier on the mind than getting exhausted on a regular bike with a flat tire. Similar with swimming with slick gear versus swimming with long shorts and a shirt.


There's something to be said about overloading the effort required though. We used to train endurance by dragging a tire behind us in the water. When it came to race day, everything would feel 10x easier.


> This reminds me of my own wacky idea for a line of fitness products: ordinary everyday items that are normal in every way except that they are intentionally designed to be physically challenging to use.

Not exactly an everyday item, but people who want to train for "tactical" things with ballistic armored vests, either because they work for a PMC or are actually in the military, can buy steel plates to put in a plate carrier which exactly match the dimensions of an expensive ($2000+) ceramic plate set, for weight and balance purposes and train with those.


> keyboards with 1lb resistance springs

I'm sure there would be mech keyboard enthusiasts who would find the actuation force too light on those


Not exactly the same, but this reminded me of the following excellent design gallery: https://www.theuncomfortable.com/


Famous Russian wrestler a century ago walked with a cane 16 kg weight.

For simple mortals like me - while hiking I've been using the Nordic poles with 8 inches springed amortization which naturally works up your upper body.


> remote controls that weigh several kilograms

That would require either very expensive metals, or a giant remote control.

But something like this is already done - a lot of people use leg weights as an extra in the gym.


1kg of lead is like 90mL. I just measured my quite svelte TV remote at 22cm x 2cm x 5cm = 220mL. I'm sure you could easily fit 1.5 kilos of lead in there, and with a slightly thicker "A/V receiver" style remote we could easily make that 3-4kg


Unfortunately the venn diagram between "people who want a heavy remote for physical fitness reasons" and "people who will absolutely lose their minds when they find out it has lead in it no matter how safely you have encapsulated it" is pretty close to a circle.


That's OK, the lead remote is simply an anchor pricing option (heh), we can sell those people a luxury tungsten weighted remote instead!

As an added bonus we can pack in 70% more mass in the same space


Along the same lines, I’ve wondered why gyms don’t hook up all their weight machines up to a big generator. Gym members would be paying the gym to reduce the gym’s electric bill.


Kind of the extremely radical opposite to the reasoning behind accessibility, then? Ever have someone in a wheelchair get mad at you?


Good luck catching me on their intentionally-hard-to-push chair.

Think of the profits from thiw move fast and break things approach! Always be hustling.


Move slow and get ripped


What about just wearing a weighted vest?

Another interesting idea I've had many many years ago: Skies that have enough buoyancy to be able to float on the sea while a person is standing on them. Do that you ski across the sea. Although the movement would be closer to rollerblades, due to lack of hills.


What you're describing would be called "skate skiing" on snow, and it's absolutely a thing. Not pooh poohing the idea, but imagine the fun of a loss of balance on the open sea. It'd make a waterski crash look downright convenient.


Yee! That's where I got the idea for it. Because my family we didn't have the normal skiing gear but instead always did the skate skiing.

That's where my idea came from.

Also just walking on water seems quite cool!


The door idea is a safety issue, but there's a market for a gag-gift remote control holder that's a barbell, for sure. Whether it helps anyone is an open question, but it hits the sweet spot for twee Americana gas station stuff.


Or just have kids.

I am picking up a 16kg and a 12kg masses several times a day, and I am sure that this keeps me in shape. Basically, because I didn't have time to go to the gym in the last five years.


It seems like anyone who’s a lazy TV watching bum would get RSIs from their remote control. I know my Apple TV remote does this to me when I use the integrated touchpad.


> doors that require a lot of force to open

These already exist! Especially when a door opens outward and it's windy outside and the wind is pushing against it.


Google "rucking"

Basically you put some bricks or weights into your backpack and take a walk.

And yes, it is a thing.


This has got to be the dumbest idea that I have ever heard of.


Have you heard about fork-axe?



they call it functional training


My favorite part of this project has got to be the helmet. For one, because it's pure concrete, with no metal frame inside it like the other parts. And second, because it best illustrates the utility of the project in that a concrete helmet is literally worse than useless.


> a concrete helmet is literally worse than useless.

Is it? It would still absorb energy upon impact. Which, in contrast to popular belief about bike helmets, is its main function. Yes, ordinary bike helmets will also just break. But in doing so, they absorb energy which then won't be absorbed by your skull.

There is no point in a perfectly stiff helmet. It would just transfer the energy right through and you'd crash your skull into the helmet, which doesn't help.


It may not be as much of a factor at bicycle speeds, but I've read that heavy helmets can dramatically increase whiplash in things like motorsport. The increased mass on your head means higher forces trying to rip it off. Obviously the other benefits of real helmets outweigh that issue, but I'd imagine a concrete helmet with very poor shock absorption and very high mass would not fair so well.


Concrete is pretty stiff. But mostly, wearing such a helmet will make it much harder to move your head around to scan your surroundings, increasing the chance of accidents.


Next challenge: the lightest concrete bike.

Concrete canoes are a thing civil engineers make for fun [1]. Weight can come in at under 10kg [2]. That's about half the weight of a typical canoe [3].

On that basis, one might be able to build a concrete bike that is lighter than a typical bike?

[1] https://www.asce.org/communities/student-members/conferences...

[2] https://www.concrete.org/Portals/0/Files/PDF/20-1stPlace-Kon...

[3] https://paddlecamp.com/how-much-does-a-canoe-weigh/


In the late 70's ferro-cement sailboats were a thing. I watched one get built at the marina where we kept our boat at the time. It's mentioned here [0], the Sandpiper.

[0] https://books.google.com/books?id=COilQT7iWTgC&pg=PP436&lpg=...


My friends live in a 80s cement boat, and have done since they built it. Was brilliant but now uninsurable, and they are stuck unable to move it and worrying about every stormy day. That said, for over 20 years it was great, but once water gets in the cracks...


The level of maker youtube projects has been going off the charts.

Some examples from less well-known creators:

Drunk Mel Gibson arrest diorama https://youtu.be/2UoHb0ziMDA

Knife throwing machine https://youtu.be/-BKEZbYOMpI

3d printed harmonic drive https://youtu.be/Emvo3bLT-Z4


The knife throwing machine reminds me a lot of the slingshot channel:

https://youtube.com/c/Slingshotchannel


Have you seen NightHawkInLight:

https://www.youtube.com/channel/UCFtc3XdXgLFwhlDajMGK69w

LaserSaber:

https://www.youtube.com/channel/UCIKzUKkh7XtnSYPW0AJb-9w

or StyroPyro:

https://www.youtube.com/channel/UCJYJgj7rzsn0vdR7fkgjuIA

They have similarity to the Quint BUILDs channel that the knife throwing machine video came from. They all do some pretty crazy builds.


Let me show you its features!


when I lived in JP (a part of Boston) I made my commuter bike "unstealable" by taping it and putting joint compound all over the frame. The thing was ugly as sin and looked at lot like this bike.

I could leave it locked with one of those cheap combination cable locks, and no one ever took it.


Do you happen to have photos of the bike?


I do this with extension cords, bit of electrical tape and most potential yoinkers will think twice about yoinking.


I do this to my own body - bits of electrical tape - I am virtually un-kidnap-able now.


I like this. But alternatively, couldn't that make it look abandoned and possibly have the opposite effect?


It didn't look abandoned, it looked ugly as shit, but definitely not abandoned.

Sadly I can't find pics. It was not a bike that photographed well.


I strongly suspect that the steel reinforcement used in the frame could have acted as a rigid enough frame without the concrete


It sort of does. You can see the fork got damaged mid-span in some of the riding shots. Still there isn't enough strength in places like the fork ends or crown without the concrete.


I strongly suspect they could just as well have used a normal bike and cast the concrete around it (which they did for some parts) ...


I suspect that the concrete will crack if it is just molded to the frame itself. Concrete cracks easily without support.


correct, it is a steel framed bike, covered with concrete - not a concrete bike.


Since most practical uses of concrete uses some kind of reinforcement this is still a concrete bike.


It’s steel reinforced concrete. That’s how houses out of concrete are built as well.


Oh there’s a lot of fun concepts to muse about. But one is brakes.

That aside, at least it wouldn’t get stolen in Amsterdam.

Which reminds me of something a friend did. He lived in a neighborhood where anything visible would be stolen. So he took an old computer tower case and filled it with concrete. Then he left it on his front porch.

Predictably some guy tried to steal it. The poor fool managed to move it one house over before giving up and dropping it in the street.


Rather misleading since the concrete isn't even structurally integral to the bike. It's more like a rebar bike that had concrete poured on it.


The same thought went through my mind watching it, but you could say the same about most (many?) concrete structures. Someone with a structural background could explain better, but I believe the rebar and concrete provide different kinds of strength, like concrete is compressive strong (and keeps the minimal amount of rebar from moving around and bending, while the rebar keeps the concrete from cracking. Even for the bike, it wouldn't be the same structurally if they just wired up a rebar frame


> but I believe the rebar and concrete provide different kinds of strength

Yes, concrete provides great compressive strength, but is not very strong given tensile loading.

Rebar provides the tensile loading support that concrete alone lacks.

See: https://en.wikipedia.org/wiki/Rebar


I took civil engineering a long ago in college but diverged on my career. This is what I recall.

In reinforce concrete beams the bending causes compression on the top and tension on the bottom. Since concrete is weak in tension (maybe 1/10 of compression strength), the rebar at the bottom will carry the tension. When you do the design calculations, some approximations are made like concrete carries no tension on bottom half of beam and how the stress is distributed on the top portion. Then with iterative analysis you can converge on an solution. Then once you got the basic design, there will other rules like displacement, buckling conditions.

Here is an example design calculation I could find: https://civilengineeringbible.com/subtopics.php?i=32


Yes, but it doesn't matter for a bike. Riding it is not going to crumple that amount of rebar.


The front left fork failed. You can see the crack in the video as he is riding. The front fork has a bending moment as well as compressive force. When the bending force was applied the concrete failed and the rebar did not.

Overall, I really liked this as an art project. I'm not sure what the artist wants to communicate with the bike, but I found it very satisfying.


How much of this can you just chalk up to using concrete and just copying the design of a normal bike? This is a fun art project but doesn't seem like much more.

Sorry for being negative about an art project. I think I was projecting my own biases, but it sounded like an engineering project and then I didn't learn anything.


I'd like to think they're reminding us why we don't make bikes out of concrete (but we can!).


> I'm not sure what the artist wants to communicate with the bike

"I paid a lot of money for an architecture degree I'm not using."


I suppose the technically correct term would be reinforced concrete bike


I would say "I covered a bike in concrete" would be the most accurate title.


to be fair, large amounts of the frame are not just merely covered in concrete


Yes, and the entire thing is either reinforced with rebar or structurally dependent on actual bicycle parts. You could argue that the rebar reinforcements, if welded together, would make a sufficient frame and the concrete is primarily acting as a bonding agent.


It seems like they could achieve the same results by pouring concrete around a real bike frame (instead of build a bike frame out of rebar).


The combination with steel is what gives concrete its power. It's a composite material created by the two things together. Concrete surrounds the steel frame and penetrates it. It binds the steel together.


Reminds me of those yearly engineering competitions where students build canoes out of concrete and race them: https://en.m.wikipedia.org/wiki/Concrete_canoe


Ah my Civil Engineering student years.. Except my year, because the year before the canoe wasn't right, and the sponsoring professor swamped the thing and took a year off (or so was the rumor), so our class never got to build one.


At https://youtu.be/Yqgn-qlg1X0?t=312 I wondered why the back dropout* was facing upwards but then later at https://youtu.be/Yqgn-qlg1X0?t=1109 they seemed to have fixed it?

* the part of the frame that attaches to the wheel


I was wondering that too, thought I missed something.


The frame is upside down. You can see the bottom bracket is on top, and the seat tube is facing down.


oh yes you're right!!!


And the reason it's easier to make than a wooden bike is that you can take a normal bike and pour concrete onto each element.


William Osman on YouTube made a bike fully out of wood: https://www.youtube.com/watch?v=0yJdz-kjfLk

[haven't finished the video yet, not sure if this or something similar was mentioned]


Someone in the UK made a wooden frame: https://youtu.be/jd0vt5v37B0


I am just locking up this bike. Why? So no one steals the bike rack.


I remember in the 1980s Bicycling or some such magazine wrapped a road bike in concrete, called it a composite bicycle and did a full review. Needless to say, it scored poorly.


Wouldn't this be a "cement bike?"

I don't see any aggregate.


So now bicyclists can suffer the same class of life-threatening injury that motorcyclists do!


I have to guess that in some forms of cycling you can still get motorcyclist style injuries... downhill racing and slopestyle come to mind.


Yes, especially around these parts. There’s all kinds of blind curves, with no shoulder, and awful drivers, all around.

But motorcycles weigh a lot, and, quite often, that weight causes grave injuries, even at fairly low speeds (like sanding off your leg).


True, I suppose it's the types of injuries that will differ most between bicycling and motorcycling. You won't see many flesh burns from touching hot bicycle parts either.

Nonetheless, severity can get a lot closer. Shiny side up!


The main thing it seems to be missing is brakes.


Its fixed gear. Your brake is to stop pedaling.


I thought so too, but at 20:55 you can see the rider stop pedalling while still rolling. It seems to contain a freewheel mechanism: https://youtu.be/Yqgn-qlg1X0?t=1255


It's a "coaster" hub, very common on cheap single-speed bikes. It allows you to coast without pedalling, and by applying backwards pedal pressure it activates a drum brake.

Definitely not enough braking force for this bike weight though.


Yeah. Good luck stopping that thing with a bit of speed. Notice that in the video he always pedals super slowly.


If nothing else, it’s a good way to get in shape


If that shape is flat...


Or break some limbs.


Reminds me of a story that happened in Russia. A store offered a discount on buying new bikes if you turn in your old bike. The discount percentage was equal to the bike's weight in kg. One clever guy built a bike weighing 113 kg. It actually worked and he got a very expensive bike for free

https://bloknot-rostov.ru/news/rostovchanin-sobral-velosiped...


Why did they mirror-image reverse the shot starting at 19:46? Bikes aren't symmetrical: the gearing is on the wrong side.


Waste of resources to do a YT hype. It's not a concrete bike, its a reinfoced concrete bike (a steel + concrete bike). Withe the amount of steel used a just-steel bike could have been built.

There's just a bit of concrete on the outside of the otherwise quite regular bike. Well done /s


Imagine getting hit by a car.

Poor car.


That's the thought I had; at least the car would take some damage.


It's similar weight to a small motorcycle.


This is a metaphor for poorly designed software. Don't worry we'll optimize it at the end!


I have always wanted to make a mountain bike out of scaffolding poles in order to review it positively.

Notionally such a bike should score highly in many key metrics. In the review the obvious failings are overlooked yet the reader can work it out for themselves.


That's brutal.


Not a whole lot of engineers on here I guess?

https://en.wikipedia.org/wiki/Great_Northern_Concrete_Tobogg...


It's great that he added concrete steps for creating the bike.


This is also how google approaches product design


I have seen plenty of bikes that could pass as sculptures but this is the first sculpture I’ve seen that could be used as a bike.


Bikes are incredibly simple devices, it's amazing that they were not invented up until 200 years ago.


No they are not. Most people can't explain off the top of their head how the derailleur works to move the chain from one cog to another, or how freewheeling allows the wheel to move without the pedals to move, or even how the cable allows brakes to be remotely activated from the handlebar. Most people can't even explain why it is possible for a bike to be stable while moving but can't stand on its own. It's counter-intuitive.

There's plenty of ingenuity in the design of a modern bike.


Most of what you're describing isn't necessary for a bike. A fixie bike doesn't have a derailleur or freewheeling. And you can slow down without breaks.

You can even remove the chain. A penny-farthing bike is a surprisingly simple device. It is surprising it wasn't invented earlier.

My guess would be that they weren't invented earlier because they are not that useful without good roads.


My uneducated and probably missing a piece understanding is it was the other way around: good roads were demanded by and built for the cyclists.

I wonder how serious the improvements in rubber (esp. vulcanisation in the 1830s) were for the practicality of bicycles.


Bicycles were invented before tires, they were called boneshakers for that reason.


The chain requires some pretty fine engineering. Arguably jewelry makers had it.



Rubber. It's a product of the Americas, before that, wheels sucked.


the steering geometry of a modern bike is not entirely obvious, most configurations are either unstable or unsteerable. Plus a bike is unusable if you don't know how to ride it, so even if you stumbled on a stable steering configuration you might give up on it before you learned to ride it.


When I was a kid I taught my neighbor kid to ride a bike by rolling him down a hill. He crashed eventually into a wall (tangentially, so no great damage to him or to a bike), but he did ride bicycle after that crash course, no problem.


I'm glad they included springs on the seat, otherwise that could have been an uncomfortable ride.


I wonder if they could make one from Iridium now. Now that would be flashy.


Only ex-bodybuilders turned bike thiefs would think of stealing that!


Finally, the secret to how those bike-share bikes are made.


Now don't take this near any hills


A concrete hat? A step too far!


Sounds like a bulldozer. Love it!


seems to have just about as much steel, if not more, in it as a regular bike..


The DeLorean went to far back.


Yes, but why? And isn't it more of a bike covered in concrete than a concrete bike?




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