Original subtitles

[upbeat music playing]

Okay, everybody, let's just take a moment.

Just realize this is a historic moment.

This is the first time this car has ever

driven like this in 30,000 years.

-Yeah! -Yeah!

[narrator] Meet the team...

Whoo-hoo!

There's a potential that I could get electrocuted.

[explosion]

[narrator] ...with the mechanical expertise...

More oxygen, more fuel, that makes more power.

[narrator] ...to test all things automotive.

[laughter]

[Bisi] It's almost like surgery.

If I make a mistake, we'll blow up the engine.

[narrator] This is Motor Mythbusters...

This is our job!

[narrator] ...where science meets the streets.

[upbeat music playing]

Now when I was a kid, I drove across country

with my parents to the Grand Canyon,

and we stopped at this FlintstonesAmusement Park.

Wow.

[Tory] It was the weirdest thing.

You walk in and it's like you're in the cartoon.

But it was like super creepy because it was just me and my sister,

the place was empty,

and they had actually fabricated

-aFlintstones car. -[Bisi] Wow.

We got in, tried to push it, but it was, you know, a prop.

It wasn't going anywhere.

But ever since then, I was like,

"Someday, I wanna build that Flintstonecar

and see if it would work."

That's what we're gonna be testing in this myth.

Do you remember that cartoon? But it might be before your time.

I don't think I've ever seen it, but some pictures

are like ringing true in my mind.

All right. So carry on.

[Tory] It was the first animated sitcom.

It beatThe Simpsons by like 30 years.

And it's basically set in the prehistoric times.

You had cavemen, cavewomen.

And it was a prehistoric fantasyland,

but it was infused with tons of modern technology

that couldn't have existed at the time.

[narrator] Okay. So according to the cartoon,

the Flintstones' car was made of two giant stone rotor wheels,

a tree trunk chassis, and a convertible canopy.

That's a heck of a lot of mass.

The first part of this myth is to test

if a heavyweight vehicle can overcome

friction and inertia using foot power.

And if it does move, the second part is to see

if a rock-wheeled vehicle can handle running

at the highway speed shown in the cartoon series.

[Bisi] Fred was a really big guy.

He was the biggest character in the entire series.

He had to be at least six foot tall.

All right. Well, let's figure out how big we're gonna make this thing.

And we're gonna sort of base it on the idea of Fred

-being six feet tall? -Being six feet tall, yeah.

I mean, I'm guessing the diameter will be about two feet.

[Faye] Mmm-hmm. So it would have to be about 10 feet long.

[Tory] All right. So it looks like in the cartoon,

the wheels are made of stone.

Time out. Time out. Time out.

With stone, it's gonna be ridiculously heavy,

and then their rolling resistance will be off the scales.

Getting it moving and stopping is gonna be huge challenges.

Fred use his feet to accelerate the vehicle and stop it.

That's bananas.

-Was he barefoot? -[Bisi] He was barefoot.

He had no foot protection whatsoever.

[Tory] But he has massive feet.

-[Faye] Okay. -[Tory] So that's a lot of surface area.

And speaking of rolling resistance,

I'm not seeing any bearings right here.

-Yeah. -That looks like wood on wood.

Isn't that how they made fires back in the day?

That's a great point.

-[Faye] Is there steering? -[Tory] But maybe...

In the cartoon, it doesn't look like

there's much to make it steer.

-[Bisi] Ooh, this is gonna be interesting. -Yeah.

I think this is gonna be something for all of us to try to drive,

'cause I don't think one of us alone

is gonna be able to get this car to move.

What do you say? Shall we [clear throat] yabba-dabba-doo this?

-Oh, my God. -[laughs]

I thought you said you haven't seen the cartoon.

A little research, you guys.

You nailed it. You nailed it.

[upbeat music playing]

[Faye] Before we can road test our foot power

and see if this thing will actually move,

we need to build it.

So Tory sourced some prehistoric materials.

[lifter horn bonks]

[Bisi] Oh, my goodness.

I got the perfect material for the wheels.

[Faye] Material for the wheels?

[Tory] Limestone.

[laughs]

-Okay. -[Faye] Okay.

It's gonna be perfect, because it's gonna be soft enough

where I can actually, you know, carve it

-into the shape that we need. -[Bisi] Right.

But it's gonna be durable enough

that we can use it as wheels.

Oh, all right. Sure.

So I'm gonna reinvent the wheel here.

-Literally. -Mmm-hmm.

Fair enough. All right. What's...

What's up with these...

The crystals?

-Oh. -These are actually my tools.

I'm gonna use the quartz, 'cause it's gonna be hard enough.

I mean, I figure back in prehistoric times,

they would have had primitive tools.

-[Bisi] Right. -So the quartz would...

You know, I could use them as chisels to carve my shape.

-This... -What do you think?

-Uh... -Keeping with the prehistoric materials.

I feel what you're trying to do,

but that looks like a lot of work.

We gotta be purists.

And also, like, I don't know, you might put some bad juju

into the... into the environment with these.

Are you feeling the energy on those?

I feel... I feel the energy.

This is not gonna work.

-Too much work for Tory. -No. This is gonna be...

-This is gonna be awesome. -[Faye] Okay.

So I'm just... Right now, I'm just gonna do like a test

just to see if I can cut a wheel shape

and see if we can get going

-on this Flintstone vehicle. -I like your vision.

[Tory] Oh, this is gonna be so awesome.

Oh, that poor crystal.

Poor Tory.

Tory, you have your work cut out for you over here.

It's gonna take him years to get that going.

He's gonna be here forever.

All right. So it's taking him a while.

We don't have all freaking month here.

And I don't know if I can find a piece of limestone that big.

I hear you. And we need to work smarter, not harder.

That's true.

I think we should consider using concrete

as an analog for limestone, and...

[Faye] That's actually a really good idea.

-Why thank you. -Because we can mold it in whatever shape we want to.

We're not gonna [makes sounds] spend all day

like, you know, shaping this thing with our hammers.

And if we do something simple like a mold,

we can get to our hardest

that's very similar to that of Tory's limestone.

-Wheels are what, 24 inches? -Yes. So maybe a 24x24, the ideal.

Yeah.

[narrator] But our Tory, ever the purist,

isn't giving up without a Stone-Aged fight.

So I went back and watched the old Flintstonescartoons,

and it turns out they had modern tools.

So forget the old stuff.

I'm going with modern technology.

Much better.

[Faye] Just in case Tory's whittling approach doesn't work out,

we're preparing for plan B.

-Beautiful. -How does it look there?

[Faye] Looks great.

Starting with a small scale test to compare the strength,

density, and durability

of limestone and concrete.

Oh, yeah. This is perfect.

All right. So one of the hardness tests that we're gonna be performing

requires a really smooth surface in our concrete.

I mean, smooth as silk.

Well, at this point,

-all we have to do is wait. -Killer.

[upbeat music playing]

-What is that noise? -What the?

[upbeat music playing]

-What the? -What the heck?

-[Tory] What do you think? -[Faye] Oh, my God.

[Bisi] What the heck?

It's my Flintstones scooter.

[Bisi] I could feel that in the ground.

[Faye] That's actually pretty sweet. Oh.

Oh, hey, those are your wheels.

[Tory] These are my wheels. I just wanted to do

a proof of concept, but it took way too long.

So I think I'm gonna scrap the whole limestone wheels for the Flintstonecar.

-We might have predicted that would be the outcome... -Yeah.

...of your venture there, so...

[Tory] I was trying to be a purist.

[Faye] ...we've got concrete in here.

We're gonna just like do some tests to make sure

that this is like gonna be similar hardness, similar weight.

-[Faye] So yeah. -Awesome. Perfect.

[upbeat music playing]

So now that this test block of concrete

is finally cured, I can actually start performing some tests.

And I'm gonna start with the Mohs scale

of hardness test.

This is just gonna give me like a good baseline of comparison.

All right. Limestone is first up.

This simple test, using tools

scaled from one to ten, increasing in hardness,

is used by field geologists to measure and compare

the surface resistance of rocks and minerals.

Okay. Very obvious to me

that I'm scratching the limestone with the four.

Now I'm gonna use that exact same procedure on the concrete.

This is a very definitive four.

So the surface hardness is just about the same.

But how will they compare under compression?

So the next test that I'm gonna be performing

is the compressive strength

of both of these materials with the Schmidt hammer.

This is actually a pretty sweet tool. I'm stoked on this one.

There's a ram inside of here that's gonna be reverberating

this little piece off of our surface,

and it's gonna measure the rebound the strength.

That penetration resistance will tell us

if either of these materials are likely to crumble

under the weight of our vehicle.

All right. So I was expecting these numbers

to be a little bit more different,

but they're really not.

Hey, our concrete mix matches the limestone perfectly

and will totally give us consistent results

for our full scale test.

[upbeat music playing]

[Faye] Look at that. Oh, my goodness.

So right now what we're doing is we're setting up

for the build of our wheels.

So we have construction tubes.

They are cardboard tubings.

One for the axle

and then one for the actual wheel.

I just wanna check and see if this is gonna be big enough.

We're gonna set that up. Glue it to the Plexiglas.

Once the glue has set up,

then we're gonna pour concrete into the tube,

which will then create our wheels.

Yeah.

That'll work.

The axle holes are integral to the build

and ultimately the myth's outcome.

If centered in a line with the chassis,

the wheels will rotate smoothly around the axle.

Nice. Nice.

[Tory] If they're even slightly off-kilter,

the wheels will skew and grind our axle to a halt.

-We are set. -Whoa.

Our concrete mold is ready to pour.

-[chuckles] -Awesome.

-All right. -Oh, my God. This is gonna save us a ton of headaches.

Oh, my gosh. Absolutely. Nice. Nice. Nice. We just...

-We really need it to center the axle. -You guys made it real tight.

That's good. This is good. You guys were very thorough.

Okay.

It'll take 16 90-pound bags of concrete to fill each wheel.

But once we have water, we're talking about 1,600 lbs of pressure

dumped squarely on the axle hole.

Right now, we gotta be really careful with how our concrete gets in there

so it doesn't offset our axle.

Have you guys verified that it actually hits to the hole

-in the perfect center? -[Tory] Like it's perfect.

-[Faye] Oh. Oh. No. It's gonna hit the top. -No. It's perfect.

-Oh, it's perfect? -Yeah.

You might wanna verify it's perfect

before you strap it down.

[Tory] No. That's good. Look.

-[Bisi] Yeah. It says perfect hole. -Look at... Look at the top.

-Yeah. I know. It's not going any further. -Okay.

-Look. Ta-da. -I gotta trust these guys, I guess.

All right. Okay. Fine.

[upbeat music playing]

[Tory] All right. That should be good.

-Easy. -Don't dump it on me.

You know, we also gotta make sure that... [screams]

[laughter]

Keep pouring nice and slow so our axle doesn't move.

I was just trying to get it to release from the barrel.

My bad. Do you wanna start vibrating the concrete?

It'll get rid of all the air bubbles.

That's gonna help the aggregate pack tight

so it's more dense and durable.

All right. This may be the last pour,

and then we will have our prehistoric wheel set.

[Faye] Number one.

-Whoa. -[laughter]

[Faye] I'm gonna spin it towards you.

[Tory] Oh, yeah. That's nice.

Even distribution. I like it.

-Okay. -[Faye] Looking pretty spot on, Tory.

[Tory] Yeah. Okay. Well, that was hard.

But we got the mold filled with concrete.

We got our first wheel.

One down, one more to go.

Yeah.

[chuckles]

Whose idea was this?

I'm gonna wear a tarp next time.

[upbeat music playing]

[Tory] The next stage of our build

is the log chassis.

We sourced some locally fallen trees

to match the specs of the original Flintmobile

and provide support for our massive concrete wheels.

[Bisi grunts]

[laughter]

Oh, my back.

These two pieces here will be our outside chassis.

-Sounds good. -Right?

In that way, we can keep

the roundness of the log

so it would look more like the Flintstonecar.

-Is this the first wood car you've ever made? -[Bisi] Yes, it is.

For some odd reason, I feel that it's gonna be much more difficult

than any aluminum or steel-based vehicle I've ever built.

Now, we have the template done.

In the eloquent words of Faye,

let's yabba-dabba-doo this.

[upbeat music playing]

[saw whirring]

[Tory] So the Flintstonecar is coming together beautifully.

We have the two main pieces of the chassis shaped.

Now we got to cut holes for our axles,

and then we have to put the two pieces together.

I'm gonna use big,

sturdy beams to connect the two,

because this thing has to be strong.

Remember, the wheels are made of concrete.

All that weight is gonna be sitting on four points

where the axles come out of the wheels.

That's a lot of weight on our axles.

[Bisi] That's a lot of stress.

Now, our axles are a little bit over five inches in diameter,

so I have a six-inch hole cutter.

We're gonna drill a pilot hole, cut our hole,

and then we could put our wheels on.

This could be disastrous

if Tory drills the hole and we go sideways.

[Tory] It's already gonna be a challenge

to get this thing to move.

Us screwing up is not gonna help.

[Bisi] No. Not at all.

[Tory] This stupid thing better roll.

-That's all I gotta say. -I hear you.

I'll be so vexed if it doesn't.

[Faye] While Bisi and Tory get the chassis in shape,

I'm turning my attention to the mechanics we need

to get this thing rolling once it's all assembled.

I still foresee a problem with the axle setup.

Now, see, on a typical car,

you have like an axle that goes into a hub.

What's in the hub? A freaking bearing.

A low rolling resistance bearing

that allows the car to move forward smoothly

without causing excessive friction and heat.

We've got a problematic situation here,

which is like the wood on the concrete.

So I've come up with a solution for that.

You know, ancient people have been using leather for quite some time.

And in place of our wheel bearing grease,

I got some lard.

All right.

The way that I'm installing this

is with the nice, smooth, tempered surface,

so that as the wheel rolls forward around the axle,

it's just gonna smoothly go over that lip.

That's the hope at least.

Now, for the moment you've all been waiting for,

the lard.

Oh, I actually think this is gonna work awesome

now that I'm feeling it.

Oh, wow. I actually think that's making a difference.

Let's see. I haven't put the bearings

in the other one yet. So a side by side comparison.

Oh, a lot of friction going on.

Wow. [grunts]

Bisi, what are you doing?

What are you doing?

I'm trying to... [sighs]

I'm experimenting to see what Fred did,

and if I can mimic that.

[upbeat music playing]

I came out here. I see Bisi.

He's like taking his shoes off.

And I'm like, "What the heck is this guy thinking?"

But he brings up a really good point,

Fred Flintstone wasn't wearing any shoes.

So for us to actually get this to work,

we have to do this bare feet.

Try leaning forward a little bit.

You might get a little bit more leverage.

-Yeah. That's good, but... -Yeah. There you go.

-No, that's good. -[Bisi] I didn't get much up to speed.

Didn't have good adhesion to the tarmac.

-And they just went [makes sound] -Yeah. Just like...

-Yeah. -But I don't have much traction.

[Tory] Okay. You know, what we should also test?

Is the braking system.

-No, no, no. Stop, stop, stop. -Okay. Brake.

No, no, no. I'm not... Ow. No.

Absolutely refuse to use my bare foot to stop.

He must have had calluses this thick.

But with this... With the toe shoes...

-Oh, see? -[Tory] Oh, look at that.

[Bisi] You feel that traction.

I like his approach. He used those little toe...

Weird toe shoes.

[Bisi] And with a little help from Tory's push start,

not only was I able to get up to speed,

I can see that we need a solid leverage point

to help overcome the rolling resistance.

[Tory] And brake.

All right. Brake.

[laughs]

I was able to stop properly.

-[Tory] Hey. -That wasn't bad.

That works better than I thought it would.

This is the way to go.

This is much better than going barefoot.

I'm definitely not doing that again.

Yeah. You know what though?

I was watching the cartoons and it got me inspired.

-[Bisi] Oh? -I got an idea for myself.

-[Bisi] Uh-oh. -[Tory] Yeah.

[upbeat music playing]

[Tory] Fred's feet are ridiculously large,

and I think that could be the secret power we need

to drive the Flintmobile.

So I got some clay.

I'm gonna sculpt the foot,

make a mold, pour it in rubber,

and then I'll have some ridiculous

Fred Flintstone feet.

This is gonna be hilarious.

[upbeat music playing]

By molding a pair of feet

to match the girth of Fred's,

I'm increasing the surface area.

Yeah, I'm gonna have the worst case of bunions,

but I'm hoping to increase traction

for acceleration and braking.

I've been sculpting since I was a kid.

And then, you know, when I was working in special effects,

we did a lot of sculpting in clay,

and making molds for body parts.

And I did a little research, watched some of the cartoon,

and it turns out Fred only has three toes on his feet.

So I don't know if that was like some evolutionary thing

or maybe the cartoonists were just lazy

and only wanted to draw three toes instead of five.

So it's been an hour since I poured the foam.

It's the moment of truth.

Let's see how our Flintstone foot turned out.

Oh, yeah.

Oh, and there you have it.

[laughs] A Flintstone foot.

[upbeat music playing]

I got so much foot power right now.

One down, one to go.

[upbeat music playing]

Take it nice and slow.

Now, it's time for final assembly

before Flintstone's car can make its debut on the street.

Keep going. Keep going. Right there. Right there. Right there.

These concrete wheels must stay

in the molded tubing for protection

until our maiden voyage.

[Tory] Look at this for a second.

-[Bisi] It's awesome. -[Tory] It's coming together.

[Bisi] Oh, my goodness.

[Faye] But the chassis and the axles

needs to be preassembled

and the wheels aligned.

[upbeat music playing]

[Tory] In the cartoon, it looks like

it has like two rows of seats.

-[Bisi] Yes. -So...

-[Faye] Yeah. They carry people... -A back row and a front row.

-Yeah. It was a prehistoric sedan. -[chuckling]

[Tory] In the cartoon, the illustrators

occasionally adjusted the car to suit the scene.

It could be a two-seater

or sometimes it carried six passengers

and a dinosaur.

For our test, we'll all sit upfront

to maximize the available foot power.

-Then we're gonna have a steering wheel. -[Bisi] Right.

And a dash so we'll have something to push off on, right?

-[Bisi] Oh. Oh. Oh. -I think we need to go a little more farther back.

Yeah. Let's try it.

All right. Ready, set, go.

[Faye] Oh, that's better. Oh, yeah.

[upbeat music playing]

[Faye] This is goat rawhide.

[Tory] It's almost like tape, creating that nice bond.

[Faye] Yeah. It's pretty good.

I keep worrying about like the angles need to be perfect,

the symmetry needs to be perfect.

No, it doesn't. It's a Flintstonecar.

[Bisi] There weren't any steering

or electrical components to house

way back in 10,000 BC.

[Tory] And although we're only testing the car's

ability to run in a straight line,

our dashboard still has an important job.

Now, it's not just aesthetic.

This one actually has to be structurally strong

because we're gonna be pushing all of our force on it

to get the car moving.

If this thing's weak, this thing could just break forward

and we're not going anywhere.

[upbeat music playing]

[Faye] Okay. Get over here.

[narrator] This epic challenge has been centuries in the making.

[Faye] Nice.

[narrator] A classic cartoon caper...

[Faye] That's good.

[narrator] ...from Tory's childhood visit

to that creepy amusement park

to this, a full-scale two-ton Flintstone's car

with working wooden axles and burlap sunshade.

[Tory] Childhood memories are just flooding in right now.

-Let's cut the cardboard tubes off. -[Bisi] Yes.

[narrator] Is the Flintmobile a plausible possibility

or a glorified prop?

[Tory] Woo-hoo!

Here it is in its glory.

[Bisi] Tory, it looks amazing.

-[laughter] -[Faye] Look at this thing.

-[Tory] We did it. -[Faye] I know.

[upbeat music playing]

-[Faye] We can't forget this. -[Bisi] Oh, that looks good.

-Oh, yeah. -Beautiful. Well done.

-[Faye] I like it. -You guys this is just...

Like it turned out way better than I imagined.

[Bisi] Faye, the canopy is wonderful.

-[Faye] Oh, thanks. -And your little rear window.

I mean, it matches the cartoon perfectly.

All right. So are we actually gonna put this thing to the test?

-Yeah. -But before we do drive it, we have a surprise.

Yeah. It might make it easier for us

to get this thing moving.

[laughs] What the...

[Tory] What do you think?

-[Faye] Are those to scale? -[Tory] Pretty much.

After watching him experiment with those ridiculous shoes,

it gave me inspiration. I thought,

"Hey, what if I made actual giant Flintstone feet?"

It will give us more surface area,

and maybe help us move this vehicle.

Who wants to drive?

Well, you can drive since this was your childhood dream.

Thank you.

[narrator] For this part one, the guys will attempt

to overcome the friction and inertia

of that two-ton Stone Age vehicle,

using foot power.

[Tory] All right. You guys ready to test this?

I'm counting down. Here we go.

Three, two, one.

Go.

[grunting]

Oh, my God. I...

Okay. Now, do I say I told you so?

[Tory grunting]

Maybe let's rock it. Let's...

Like let's see if we can get momentum going.

-Two. -Two.

[grunting]

[Tory] We're moving.

[grunting]

-[Bisi] Oh. Okay. -[Faye] Oh, look. It's working.

-[Bisi] Oh, it's moving. -[Tory] We'll be at work in no time.

-I can't get my butt of this thing. -I'm cramping up.

-All right. Let's standing. -[Faye] All right. Hold on.

[grunting]

[Tory] Yeah.

[Faye] Yup. Okay.

-Now, we'll [indistinct] -[Tory] All right. Ready? Sit.

Look at this. It's perfect.

Oh, my God.

It's amazing.

[Faye] Oh, no.

[Tory] Oh, no. My big feet are getting in the way.

[Bisi] Oh, my goodness.

[Tory] These stupid feet.

[Bisi] We have to be nice to this [indistinct]

[panting]

That's a good workout.

Maybe the cavemen were in much better shape.

I'm gonna swap out these big, ridiculous feet

because they're literally just getting caught up

in the wheel works.

You know, what we need is like the US bobsledding team

to help us push this.

Three, two, one.

[grunts]

-[Faye] Uh-oh. -[Bisi] What the...

[Faye] Uh-oh. We got this.

-[Tory] We need a downhill road. -[Bisi] Yeah, we do.

-[Tory] It'd be so much easier if we were going downhill. -[Faye] Uh-huh.

[Bisi] You know, this is not an efficient means of transportation at all.

[Faye] This is not an efficient means of transportation.

[Tory] But it's a great form of exercise.

-[Faye] What? -By the time we get to work, we'll be ripped.

[Faye] Okay.

[Tory] All right. All right. Let's coast.

-Isn't that nice? -[Bisi] Oh, I feel that.

[Tory] A few seconds of coasting?

-That's heavy. -Faye, do you feel that burn?

-Your legs are... -Yes. My quads...

-[Bisi] Yeah. -They feel like they're on fire.

-Okay. -[Bisi] Okay.

We should have... We should have picked a better route to work.

-Yeah. -[laughs]

You should have chosen one that was all downhill.

-Yeah. -All right, you guys.

So what do you think?

Well, I think...

We did cover some good distance.

Yeah. And I feel like we have proven

that you can get it started just by feet

and stopping it just by feet.

But we, you know, didn't come anywhere near

like road speeds.

I couldn't drive this to the office.

-Yeah. -No.

[Tory] What do you think, Faye? You still doubting this vehicle?

-[Faye] Are you... Is that really a question now? -[Tory laughs]

If we were to get it up to speed,

would this vehicle even hold together?

Oh, my God. Faye, he has that look in his eyes again.

[Tory] You bet I do, Bisi.

Time to test the second part of the myth.

Let's see if this beast holds together

at Bedrock Highway speeds.

Once we have this hooked up, we'll back a truck up,

put that up, and then we're going for a ride.

[Bisi] Fred is a pretty big cartoon dude.

I figure he can get to a max running speed of...

Let's say at least 25 miles an hour.

[Faye] That's a lot of friction

for a leather and lard bearings.

I hope they hold up.

[Tory] All right, say hello to our cave busters.

Since this is too dangerous for us to ride in,

we're gonna have our busters driving.

This has got like a hundred percent weirder.

-[Faye] There. -We're good.

All right. So we have our towing hitch

attached to our Flintstone car.

We are gonna drive down the road and see

if this vehicle will even hold up

under those types of speeds.

I'm smiling 'cause I think the undulations in the road

are gonna destroy the thing, but we'll see what happens.

-We'll see. -Yeah. Do you do like bets?

I'm consciously optimistic.

[upbeat music playing]

Okay, everybody, let's just take a moment

and just realize this is a historic moment.

This is the first time this car has ever

driven like this in 30,000 years.

She's holding together.

What speed are we at?

Seven miles an hour.

[Tory] We're looking good.

-[Faye] Look. -[Bisi] Ten miles an hour.

[Faye] It's like thrown up debris.

[Tory] Yeah.

This is the weirdest thing I've ever seen.

Fifteen.

[Faye] Oops. That's fast.

[Tory] This thing is bouncing around like crazy.

[Faye] It's gonna come apart.

-Look at that wheel. -Slow down. Slow down.

Let's stop and take a look at what happened.

-[Bisi laughs] -[Faye] So...

-Fifteen miles an hour. -This thing was bouncing around.

[Faye] Fifteen?

-[Tory] What did you get up to? -[Bisi] Fifteen.

-[Tory] Fifteen? -[Bisi] Oh, we lost... we lost...

-we lost our backseat driver. -[Tory] Oh.

-[Bisi] That's the problem. -[Tory] Maybe that's what happened.

-[Bisi] That's a problem. -[Tory] 'Cause this thing was bouncing around like crazy.

[Bisi] Yeah, because we lost one of our busters.

So our backseat driver got dislodged.

It got actually stuck underneath the back wheel.

And that's when the backend of the car started bouncing.

So we're gonna remove him and go for another test.

It's working.

[upbeat music playing]

[Bisi] This is it. We are going for the running road speed

of 25 miles per hour

just like Fred in the cartoon.

[Tory] All right, Bisi.

How fast are you going?

Five miles an hour.

Ten miles an hour.

Oh, my God. Look at... Look at the back axle.

[Faye] Yeah. It's... Oh, pin's about to come out.

-[Tory laughs] -[Faye] The pin's about to come out on this side.

[Tory] Oh, my God.

Seventeen miles an hour.

[laughter]

[Tory] Little pieces of debris are coming off the wheel.

[Faye laughs]

[Tory] What did we get to?

-It was too much. -[Tory laughs]

All right. Why don't you go ahead and stop

and we'll take a look.

Giant chunks of concrete were coming off

the back of the wheel.

I saw that and that's why I pulled back a bit.

I had to stop because I felt immediate instability and...

[Faye] That pin flew off.

-[Bisi] Oh, no. -[Tory] Oh, my God.

We split the wheel.

[Faye] Oh, my God.

-No wonder. -Oh, my.

That's awesome. This makes me so happy.

-What did we get up to? -Eighteen miles an hour.

And all you need is a straight commute to work

and you're good to go.

[laughter]

That was so much fun.

I can't believe we built the Flintstonecar,

and it was better than the one I saw

when I was a kid in Arizona.

Yeah. This was no prop.

No one is as surprised as I am.

I did not expect that thing to roll at all.

And your bearings, they worked perfectly.

-Mmm-hmm. -So what do we think?

Well, I feel like the first part of this myth is plausible.

We were able to start it with our feet and stop it

and we got the vehicle to roll.

Yes, I agree. However, the second part is totally busted.

There's no way that it's practical to run this thing on a highway.

I agree. When we got that thing up to speed,

it pretty much self-destructed.

Yeah. That was awesome.

I don't know about you guys though.

This was a childhood dream come true.

Would you say yabba-dabba-did it?

Oh.

[laughs]

You win.

Ugh, the feet of shame.

[upbeat music playing]