The reason for the gears on the right is so when you take a picture, it has the appearance of going forward. Same reason most old steam engines, cars & ships was photographed or painted from their right side. It gives the illusion its headed forwards or towards the future.
7:04 The earth spins counter-clockwise in the northern hemisphere (looking from the north pole) and clockwise from the point of view from the South Pole in the southern hemisphere.
If you go on a long range fishing trip outta San Diego, by the time you get to the equator your bait is dead cause now it can't swim in the opposite direction. Only matters if you like lotsa anchovy on your pizza.
It's a convention, and it would be pointless to have 2 competing standards when neither offers an overwhelming benefit. Right hand threads are easier for the right handed majority to tighten. By the same argument, left hand threads are easiest for the right handed majority to loosen. For comparison, in the world of motorbikes, the rear sprocket is not screwed on but is held on with several bolts so the handedness of a single central thread is not an issue. A motorbike drive chain is usually, but not always on the left. This is because most people usually mount from the left, so the kick stand is on the left to lean the bike that way. Therefore the chain is on the "downhill" side and more sheltered when the bike is parked in the rain. The explanation about mounting from the left due to the sword scabbard is interesting.
Not sure about that, drivetrains on motorbikes were primarily influenced by the engineering constraints of crank rotation, transmission design, and the cooling advantages of mounting the engine with exhausts forward. Counter rotating cranks are a relatively recent addition, utilised to recruit crank rotational inertial forces to counter other rotational forces exerted by wheels disks etc.
@@space.youtube It's also true that most swordsmen held their sword in the right hand and their shield in their left hand. A soldier would need to drop his sword to shake hands, which is why we shake hands with our right hands.
Love geeky historical content. Ive often wondered why motorcycles are the opposite to bicycles until i saw some early motorcycles in a museum. I noticed they were basically bicycles, complete with right-hand side drivetrain with an engine bolted in the frame and a second drivetrain powered by the engine on the left-hand side. As motorcycles evolved and went in a different direction, perhaps the left-hand side drivetrain remained once the pedal cranks had gone?
Interesting info! I'm left handed myself, and when I was kid and starting my bike life, I always intuitively unmounted to right side of bike, and had to lean over to put kickstand down by hand. I had to learn to unmount to left consciously.
I saw this video title, thought it looked interesting, and put it in my watch next queue. As soon as you posted the question I immediately thought about tightening threads, but the forces on ball bearings made more sense than I had ever thought of before. Never even considered the Archimedes Screw. Very, very cool, and I've learned something today
Due to the fact that most people mount and dismount their bicycles from the left, when they lean then up against walls and fences it is usually the left hand side you see - which is against the rules for the bike vault. So imho left side drive trains are clearly superior (also cleaning and relubing the chain is such hard work on right hand drive trains because you first have to turn the bike around). 🙃 Apart from that I don't think it really matters in every-day scenarios: I always found riding a bike with my sword on quite cumbersome. Luckily we have cargo bikes nowadays so we can put all our weaponry in the cargo tray/luggage compartment. This makes besieging castles on two wheels so much more enjoyable. Happy days.
2:47 The moment I realized this, some years ago, was one of the most happy moments in my very amateurish career in bicycle engineering 🤣 Thanks for illustrating this so nicely, that's exactly how I pictured it in my mind.
Wait.....doesn't the earth only spin counter clockwise if you arbitrarily assign the North Pole as the top? The South Pole is just as valid a top as the North, after all, there is no up and down in space.
Yes, but that is the default though, since the vast majority of people live in the northern hemisphere, so that is kinda considered to be the top. Like it is on the vast majority of maps.
@@DejanOfRadic I don't know, that was definitely a bit of a leap of logic that I didn't quite understand either. But saying that the earth rotates counter clockwise wasn't the bad part.
So in the '70s a Canadian track cyclist had an experimental design with 2 drivetrains. The left side was set up with a freewheel, it would be the drivetrain until it was unwound. The right side was set to wind up and lock, so it would be a bigger gear. Not sure if it got banned, or was just too heavy for the Kilo. Jocelyn Lovell was the cyclist.
Pragmatically, in countries drive left side of road (here in Japan, UK, and Australia) should have benefit having drive train on the right side; for avoid road side weeds sticking to drive train parts. So I'm pretty happy with having it on the right side especially every time I ride gravel or off road.
I've recently built a left-hand drive fixie. For the rear wheel the hub is Hope Fatso front hub, with sprocket bolted onto the rotor mounting. It's a nice red one. For the cranks it's a set of alloy ultra torque mounted back to front, with the threads for the pedals drilled out and helicoils fitted to reverse them - theyre still left hand thread on the left hand side right hand thread on the right hand side. But I realised is that being right-handed, walking with my left hand drive bike on the right hand side, or hoisting it onto my shoulder to carry it up stairs, is a whole new problem - now I have to make extra effort to avoid rubbing against the drivetrain; or pick up tattoos on my leg, or clothes... Id assumed that the reason for the drivechain being on the right hand side (usually!) is to keep it out of the way for the biggest number of people. I've recently read a book on the history of bikes which suggested that drivetrains in the early years could be found on the left or the right depending on the manufacturer.
I enjoyed this discussion on a topic I hadn't thought about much, if ever. I had just thought the drivetrain location was related to nautical tradition. The starboard (right) side of a boat or ship relates to where the rudder was traditionally located prior to centerline rudders coming into fashion. Same for having the steering wheel and controls on the right side of the car (at least in the UK and most Commonwealth contries plus Japan and a few others). I hadn't considered bolt rotation or mounting a horse for battle in Arthurian times. Excellent video again from GCN.
This is the sort of content that's brought me back to GCN! I've never questioned the fact the drivetrain is on the right hand side - but even more weird, my track bike is left hand side and I've literally never noticed it 😂
2:23 I’ve always wondered why pedals and BB are reversed. It seemed counterintuitive. This helped answer that question. I’m so glad you are independent again. I’m actually enjoying your content. I was getting sick of all the sponsored infomercials.
I just commented on this actually, I don’t believe there is any benefit to a reverse thread on the left pedal, the pedal rotates on a bearing, so there is no force on the thread at any time -in my opinion
@@daztastic147 there's a force on the threads that screw the pedals to the cranks. And because of the different rotation directions that's why one is clockwise and the other is anticlockwise.
I read somewhere that, due to bearing reliability issues in the early days of cycling, the threads were such that the pedals would unscrew in the event of a seized bearing. The rider would be more likely to control and stop the bike in this scenario than have their clipped-in foot injured as it’s pulled around by the pedal. I’m not 100% convinced of this to be honest, but…
motorcycles similarly nearly always have the chain on the left. i think this is because the brakes are operated by the right hand (front brake) and right foot (rear brake), and traditionally the rear brake was a drum-type design that had a mechanical linkage to the pedal actuator. by placing the chain on the left it cannot interfere with the brake. additional head cannon: kick stands all lean a parked bike to the left, and i think this was intentional to keep the chain (which requires lube & care) sheltered out of the weather as much as possible.
It's the effect of *precession* that tightens pedal axles and English-threaded BB cups. The video implies BB bearings push the outer cup in the opposite direction of axle rotation. If that were true, that force would act to *accelerate* the motion of the axle. We could use bearings as motors!
99% of bikes have their drive on the right hand side with a few exceptions, some BMX's, track bikes and mountain bikes ....and that road bike in the Eurosport advert interlude video.
Love the nerdy stuff, more please. Something I've always wondered, especially after a nasty crash on my mountain bike, is why the derailleur points down putting it closer to the ground and in range of rocks etc Surely the derailleur spring tension would be sufficient to stop the chain from sagging if it was redesigned to be flipped to point up. Or am I missing something totally obvious to why it's not possible?
The RD is positioned downwards because it's the load-free part of the chain (only tensile forces come from the RD spring). Flipping the RD to the top would cause several problems, as all the loads would then travel through the RD, cage, spring, etc. You wouldn't even be able to use a spring, as any force would just deform the spring instead of driving the bike forward. Additionally, shifting would become much more difficult-you would always need to freewheel to shift, and any force on the pedals would make it impossible. You’d also need beefier RDs and cages to withstand the forces, and there would be efficiency losses due to deformation of these parts. While you could theoretically make the chain cross between the chainring and cassette to flip the RD, that would lead to even bigger issues
I knew about why it's on bicycles that way, and why UK traffic is RHD (and why most of rest of world - other way, because chosen at times and with predominant other type of transportation, eg. carriages, not horseback riding) .. but didn't knew bits why thread is dominantly right. Interesting. Enjoyed.
I have a French-threaded steel frame. When I first got it, I would tighten the bottom bracket mercilessly. Then daintily pedaling down the road, I would feel, then see, the bottom bracket . . . slowly unscrewing! That proved why French-threaded pedals, got everyone scratching their heads, until The British-threaded pedals solved it. French-threaded bike engineering, one of the many things the French got wrong.
Time carbon, look pedals, mavic wheels, Renault F1 cars, airbus, the Eiffel Tower, Concorde, the sewing machine, the hot air balloon, high speed trains and the metric system. Here you go.
@@l.d.t.6327 Mavic R-Sys - nuffsaid, Concorde, banned from the sky -nuff said, forcefully over-feeding ducks nuff said, etc etc. Now I never said they NEVER created anything. All I deed was mention an aspect of bike threading they fked up. That's all.
@@savagepro9060 nope, I read your comment, and it’s denigrating / xenophobic towards French. It says more about you and your lack of respect. Ps: I’m not even French, but have friends everywhere and a bit less toxic when commenting.
@@l.d.t.6327 what can I say . . . To Itch His Own! Let's hope this was not . . . Talk-Sick? Oh but my Franco-Samaritan Friend, Fight! Fight! Do not surrender the . . . Little White Flag
Grest video, Connor! I knew that you usually approach a horse from the left-hand side but not why. I just thought that you always do it from the same side because horses are used to it and get nervous if you try it on the other side. 😅 If you then do the same with bikes it is more practical for a classic bike stand if the chain drive is not in the way but I guess in the beginning thought about that.
"...is it because the Earth spins in a counter clockwise direction?..." ??? Really? Have you considered the fact that the Earth's rotational direction depends on where it is being observed? And if it actually influences "handedness" why is the dominant handedness not different in the north and south hemispheres?
I don't get what you mean. Earth still rotates in the same direction regardless of which hemisphere it is observed from. If the sun is used as a reference point, it rises in the east and sets in the west, regardless of one's position on the globe. (I think. My brain is starting to hurt). Where would the observer need to be to see it differently?
The drivetrain on bicycles is always on the right due to historical standardization, ease of use for most right-handed people, and better access to the mechanical components for maintenance.
3:10 No! This is not accurate. The reason for this reversal is called precession, it has nothing to do with the ball bearings. It is more like the threads roll around slightly as the load direction changes. For a quick demo: If you hold a pencil loosely in your fist and wiggle the end around in a circle the pencil will twist the opposite direction. This applies to both the bottom bracket and crank threads, which is why the both tighten in the opposite direction that they turn.
Whatever the reason, it’s the one standard that the entire bike industry can agree on, please, let’s keep it that way. I don’t want to have to worry about buying a left/right side cassette or derailleur
It would also make sense to have it on the same side as your dominant foot, as that's probably the side where most torque will be applied. Also re swords, your left hand will also likely be holding a shield (unless you're rich enough to have a squire to pass it to you after mounting), and that would be very awkward to swing over the horse.
Pedals are actually trying to unscrew themselves as you go, rather than tightening. The left pedal has a reverse thread so that it accomplishes this. I think it is a safety feature: if the pedal seizes, it will then unscrew itself from the crank rather than separate your foot from your leg.
That's only half the answer though. Threads aren't a perfect, precise fit, and pedal threads undergo precession relative to the crank as you pedal under load. The threads are designed to tighten with respect to that precession.
Well that makes sense in the same way -> you step up on the left -> so the hot exhaust should be on the right. And you want to separate your chain and exhaust, hence the chain should be on the left. You do however need to change the screw threads.
On most motorbikes the drive chain is on the left side. The rear sprocket is bolted on and the front fits in slits in the axel. They are not hold by thread around the axel at all.
The reason the first "treads" where right handed is also because the first screws where from wood and wood is stronger left handed, which is the force applied to the wood when using the screw. That is also the reason old windmills rotate counter clockwise.
@@Long_Toe Science is not sure why wood is stronger is one direction as the other. It is probably a combination of sun and wind. Western wind is much more common.
The rotational force on the pedals loosens the thread for the same reason the BB is tightened by rotational forces. How can you make a wrong statement and then immediately provide the perfect explanation for why you're wrong? However, the loosening isn’t an issue because the rotational forces are close to zero due to the pedal bearings, but saying the opposite is just incorrect. If you want to test this, the next time you unscrew your pedals, simply hold the pedal axle in place and turn the cranks forward to quickly unscrew the pedal.
Back in the early days of bicycles the left pedal kept coming loose so they changed it to a left hand thread. It has to do with the way the thread bites as the compression force works its way around during pedal rotation.
It was demonstrated to me that it is the effect of mechanical precession. You can see how this works by putting a water bottle inside of a roll of painters’ tape. Now roll the bottle around the inner surface of the tape roll, and you can observe how this reverses the direction of the force. At a micro level, the pedal axle is actually walking in the opposite direction around the inner surface of the threaded hole in the crank arm.
First of all, the effect he showed for the rotational forces shows that the torque on the static bearing race actually goes against the rotation. The right pedal spins counter clockwise relative to the cranks, so per his explanation the torque would go clockwise, tightening the thread. So that is actually consistent. Secondly, look up mechanical precession on wikipedia, that is the actually dominant effect and the explanation why pedals don't unscrew while riding. From extensive experience with unicycles assembled wrong, I can tell you that there is enough torque on the pedal threads while riding to unscrew pedals if you reverse the thread directions.
@@Finnspin_unicyclesPrecession is correct. But the bearing description in the video is also wrong; if the bearings have the slightest amount friction, they will exert a force that is in the same direction as the moving part. If the opposite were true, bearings would act as motors😊
Imagine a world, where there was no consensus about the correct side of the drivetrain. We could have endless discussions about which side is better and the industry would want to make us believe we all need two bikes for each discipline, one with a lefthand side and one with a righthandside drivetrain. 🙄
Anti-clockwise followed by counter-intuitive gave me a giggle. Anti- and Counter- are similar prefixes. We use Counter-Clockwise in the States vs. Anti-Clockwise.
This is a thing in photography, with the lenses you can change on a camera body. The direction the rings turn to adjust focus, aperture, and in some cases zoom changes based on who manufactured the lens. Annoying to go from one system to another if you aren't used to that. And it also comes from proprietary pieces. The mounting system changes, how far away the lenses are from the sensor/film (flange distance) changes, mechanical and electronic linkages change. It's a mess. Be glad there is a standard that everyone uses, and there can't be engineering pressure to make it proprietary. Bottom brackets are annoying enough.
Interesting Connor! Always wondered about the drive train being in the right. But,… why are front brakes in the Uk on the right (and back in the left) and they’re the ‘wrong’ way round in Europe. Scares me every time I’ve borrowed a bike on the continent and pulled the ‘back’ brake
Interesting. Another reason that we drive on the left that I've come across is that in the days of horse drawn carriages, coaches and wagons, the drivers and waggoners had whips with which to encourage greater efforts, (a practice now rightly outlawed because of cruelty) because of dominant right handedness, the whips would need to be raised away from low overhanging branches and more to the middle of the road where the tree branches were at their highest.
There are notable and rather common exceptions: the aircooled Harley Sportsters (they might usually have belts though, not an HD expert, but the same principle), Buells which used the Harley engine, the classic looking modern Triumphs (Bonneville, Speed Twin, Speedmaster, probably forgetting something) and the KTM LC-4 series (edit: and the small BMW GSes). At least. Don't know exactly why these makes have ended with the right hand drivetrain, especially the Triumph, I though it would be because of "British tradition" but quickly image-searching it seems that all the classic British bikes from 50s-70s had a left hand chain, including the original Bonnevilles.
Drivetrains on motorbikes were primarily influenced by the engineering constraints of crank rotation, transmission design, and the cooling advantages of mounting the engine with exhausts forward.
A couple of billion years ago when all the continents were in the southern hemisphere - the Earth's spun clockwise! It was a pain in the ass to convert all those bicycles to right hand drive back in 3B BC !!! 😂😂
Great expalantion. Any chance you can explain why the front and rear brake lever location on the bars varies with which side of the road we drive on? Also, on motorcycles the front brake is always on the right.
Nice one! What's stopping the globe from being depicted 180 degrees offset vertically? In that case the world would spin clockwise. Great science, can't believe I wasn't already subscribed!
The bike on the video clip that follows the tv adverts on bike racing is left hand drive. They've shown this for as least 3 years. I can't believe that the TV producers haven't picked up on it.
I'd figure the main reason is the same as why sugar is all right-handed. Which ultimately boils down to why most wine bottles have dimples at the bottom, even if the wines have no use for them.
@2:25 Nope. This is the exact opposite. Pedal direction makes it looser. I've always been told that it's because the alternative would be pedals that you can never remove. But just think of when you have a 15 wrench, you basically "pedal" to remove the pedal.
It's the brain. If you ride a bike, a horse, a scooter etc all of us will get on it from the left side. The brain also feels safer in left turns. Nearly all races go counter clickwise. The chain is dirty. Therefore on the opposit side. And it is it not (and was never) impossible to manufacture left handed threads. ;-)
I’ve never understood why pedal/crank arms have a reversed thread for the left-hand side. The fact that there is a bearing arrangement in the assembly means that there is never a force on the thread in either direction, demonstrated nicely by holding the left pedal by hand and spinning your crank backwards, if there was any possibility of this loosening the thread there would be resistance
A hangover from the days of poor bearing quality. A seized bearing would result in the pedal unscrewing instead of pulling the rider’s foot around and causing an injury. So I read once, anyway.
From extensive experience with people assembling unicycles wrong, I can tell you with certainty that pedals do infact unthread if you put a right hand thread on the left and a left hand thread on the right pedal. Look up mechanical precession. You are right, the bearings produce little torque, mechanical precession does (and it goes against the turning direction of the pedal).
@@Finnspin_unicycles why don't fixie riders pedals unscrew when putting back pressure? why don't bmx riders pedals unthread when riding fakie? the answer lies in proper torque of the pedal. if your pedal is torqued properly it will never un thread. "Mechanical precession can occur when too much clearance exists between a shaft and a bushing, or between the races and rolling elements in roller and ball bearings". This doesn't apply to threaded connections. Threaded connections are designed to use the stretch of the bolt as a "spring" which holes the part in place. due to this "spring", there is a constant force applied to hold the pedal to the crankarm, and the very small vibrations that pick up through the ball bearings rolling is not enough to overcome the tension of the spring and break it loose. It requires a certain breakaway torque which cannot be applied in small amounts over time or it will never actually rotate the thread. However, if the pedal is loose to begin, there will be mechanical precession between the pedal thread and the crankarm thread, which will allow the pedal to back out as no spring tension is holding it.
@@bmxscape While properly tightening the pedals down helps, if you look at pedals, you will find that unlike proper bolts most have barely any flange. In some softer aluminium cranks, you might not even be able to get the necessary preload to fully prevent precession. Preload can also get lost by deformation of the thread or crank due to load spikes (riding down curbs for example). If properly designed for it, you are right, you can avoid such problems in threaded connections, but a century or so ago, the bike industry decided to go with opposing threads instead. Given that such parts are often changed by the end user who doesn't know how to properly tighten things, maybe it is not such a bad choice.
Connor, if your "Earth's rotation" theory holds, does that mean that creatures evolved in the southern hemisphere are predominately left handed? I'm cross lateral, ie right handed left footed (I start off on the bike with my left foot on the pedal) so should I have a bike with the transmission on the left?????
On a fixed speed bike with a single cog you can flip the rear wheel over, swap the left/right cranks and move the chain from right to left, doubling the life of the chainring and cog since the chain then uses the sections of the teeth that previously did nothing.
@@kalijasin Indeed you cannot, the freehub would then be in the wrong direction. This applies to a bike with a fixed cog on the rear wheel, that cannot freewheel. I've seen it done and it does double the life of the components.
Oh! This is an exciting opportunity for the marketing guys at the mega bike companies. Conjure up some explanation of an “improvement” (that most riders don’t need) and put out some ads showing the cool guys riding it and bam! One of the last uniformities of the industry can be crushed. Oh, oh, oh!! And then promote that LH drivetrains work even better with yet another variant of chains that are 1/8” different in pitch!!! Oh my, opening up many new forced obsolescence opportunities!
That the transmission is on the right is now very good. With E-bikes it looks better and makes it more easy to mount the electric motor in the bike. THe only bike I know that has an chain on the left side is the tandem. Although the sprocket on the rear wheel is on the right.
What reason do you think is the most plausible?
I think the Archimedes screw ( Egyptian Screw )was first used in the hanging gardens of Babylon .... Thing is, did they have freehubs ?
Well, that went deep, lol. But not deep enough. You forgot about chirality and particle spin.
Just because it feels right.
No room for kickstand.
The reason for the gears on the right is so when you take a picture, it has the appearance of going forward. Same reason most old steam engines, cars & ships was photographed or painted from their right side. It gives the illusion its headed forwards or towards the future.
This is the nerdy content many of us like. Well done GCN
I've always wondered how to mount my horse when carrying a sword. Thanks, GCN!
Surely this calls for a video on bike jousting?
To arms, to arms!! We ride at dawn!
Always ready to help
What do you mean "mount your horse"?
Now you could carry a sword when riding your bike. It think that would lend some class to the activity that is much needed
Honestly this sorta content has brought me back to GCN!
I've never even questioned why the drive train is on the same side. Weirdly
7:04 The earth spins counter-clockwise in the northern hemisphere (looking from the north pole) and clockwise from the point of view from the South Pole in the southern hemisphere.
Try telling flat earther that. Lol
@@kalijasin Hmmm... are flat-earthers also non-spinners? Even a pancake will exhibit the same behaviour :)
Yeah but which is really the top?
If you go on a long range fishing trip outta San Diego, by the time you get to the equator your bait is dead cause now it can't swim in the opposite direction. Only matters if you like lotsa anchovy on your pizza.
Everybody knows that right handedness is dominant in the northern hemisphere, while left handedness is dominant in the south. 🤣
It's a convention, and it would be pointless to have 2 competing standards when neither offers an overwhelming benefit. Right hand threads are easier for the right handed majority to tighten. By the same argument, left hand threads are easiest for the right handed majority to loosen. For comparison, in the world of motorbikes, the rear sprocket is not screwed on but is held on with several bolts so the handedness of a single central thread is not an issue. A motorbike drive chain is usually, but not always on the left. This is because most people usually mount from the left, so the kick stand is on the left to lean the bike that way. Therefore the chain is on the "downhill" side and more sheltered when the bike is parked in the rain. The explanation about mounting from the left due to the sword scabbard is interesting.
Not sure about that, drivetrains on motorbikes were primarily influenced by the engineering constraints of crank rotation, transmission design, and the cooling advantages of mounting the engine with exhausts forward.
Counter rotating cranks are a relatively recent addition, utilised to recruit crank rotational inertial forces to counter other rotational forces exerted by wheels disks etc.
Also, this might be the result because the exhaust tends to be on the right to avoid burning yourself when getting on/off the bike.
" it would be pointless to have 2 competing standards when neither offers an overwhelming benefit."
Bottom bracket - 'hold my beer'
@@bradl7439 Fair point well made.
@@space.youtube It's also true that most swordsmen held their sword in the right hand and their shield in their left hand. A soldier would need to drop his sword to shake hands, which is why we shake hands with our right hands.
Love geeky historical content. Ive often wondered why motorcycles are the opposite to bicycles until i saw some early motorcycles in a museum. I noticed they were basically bicycles, complete with right-hand side drivetrain with an engine bolted in the frame and a second drivetrain powered by the engine on the left-hand side. As motorcycles evolved and went in a different direction, perhaps the left-hand side drivetrain remained once the pedal cranks had gone?
Interesting info! I'm left handed myself, and when I was kid and starting my bike life, I always intuitively unmounted to right side of bike, and had to lean over to put kickstand down by hand. I had to learn to unmount to left consciously.
Just one more example of lefties living in a righty world.
I'm right handed and (un)mount from the right too. I place my dominant foot in the pedal that's down to initiate the movement...
I saw this video title, thought it looked interesting, and put it in my watch next queue.
As soon as you posted the question I immediately thought about tightening threads, but the forces on ball bearings made more sense than I had ever thought of before.
Never even considered the Archimedes Screw.
Very, very cool, and I've learned something today
Due to the fact that most people mount and dismount their bicycles from the left, when they lean then up against walls and fences it is usually the left hand side you see - which is against the rules for the bike vault. So imho left side drive trains are clearly superior (also cleaning and relubing the chain is such hard work on right hand drive trains because you first have to turn the bike around). 🙃 Apart from that I don't think it really matters in every-day scenarios: I always found riding a bike with my sword on quite cumbersome. Luckily we have cargo bikes nowadays so we can put all our weaponry in the cargo tray/luggage compartment. This makes besieging castles on two wheels so much more enjoyable. Happy days.
2:47 The moment I realized this, some years ago, was one of the most happy moments in my very amateurish career in bicycle engineering 🤣 Thanks for illustrating this so nicely, that's exactly how I pictured it in my mind.
Archimedes was a standout left midfielder for the Greek National Team
He played in that position on principle.😀
Wait.....doesn't the earth only spin counter clockwise if you arbitrarily assign the North Pole as the top? The South Pole is just as valid a top as the North, after all, there is no up and down in space.
This is true, and the first thing I thought when he mentioned the earth's rotation
Yes, but that is the default though, since the vast majority of people live in the northern hemisphere, so that is kinda considered to be the top. Like it is on the vast majority of maps.
@@jaspermooren5883 granted, but how does that apply to a natural predilection to screw things in tightly righty?
@@DejanOfRadic I don't know, that was definitely a bit of a leap of logic that I didn't quite understand either. But saying that the earth rotates counter clockwise wasn't the bad part.
I just commented the same thing.
So in the '70s a Canadian track cyclist had an experimental design with 2 drivetrains. The left side was set up with a freewheel, it would be the drivetrain until it was unwound. The right side was set to wind up and lock, so it would be a bigger gear. Not sure if it got banned, or was just too heavy for the Kilo. Jocelyn Lovell was the cyclist.
Pragmatically, in countries drive left side of road (here in Japan, UK, and Australia) should have benefit having drive train on the right side; for avoid road side weeds sticking to drive train parts. So I'm pretty happy with having it on the right side especially every time I ride gravel or off road.
And Indonesia, India, Thailand, much of southern africa, and NZ. Here in France I need to mount the bike from the traffic side.
Connor Attenborough 👍👍
The majority of us is right handed. This could be the closest answer. Same as guitar position.
Exactly!
But why would they place the chain on the left side of most motorcycles? Especially since most motorcycles companies used to produce regular bikes
@@SestoEIemento they’d based on kickstarter.
The guitar position depends on how you string it. You can string the same guitar for a right-handed person or a left-handed person
I've recently built a left-hand drive fixie. For the rear wheel the hub is Hope Fatso front hub, with sprocket bolted onto the rotor mounting. It's a nice red one.
For the cranks it's a set of alloy ultra torque mounted back to front, with the threads for the pedals drilled out and helicoils fitted to reverse them - theyre still left hand thread on the left hand side right hand thread on the right hand side.
But I realised is that being right-handed, walking with my left hand drive bike on the right hand side, or hoisting it onto my shoulder to carry it up stairs, is a whole new problem - now I have to make extra effort to avoid rubbing against the drivetrain; or pick up tattoos on my leg, or clothes... Id assumed that the reason for the drivechain being on the right hand side (usually!) is to keep it out of the way for the biggest number of people. I've recently read a book on the history of bikes which suggested that drivetrains in the early years could be found on the left or the right depending on the manufacturer.
could/would watch videos like this for hours, ty all
This went in a direction I couldn't have known from reading the title. It's absolutely brilliant! Thank you for these insights into human evolution! 💚
Finally someone acknowledges the historic/ equestrian reasons! 🤩
When I try mounting my Scultura from the right my sword always get stuck in the frame somehow.
I enjoyed this discussion on a topic I hadn't thought about much, if ever. I had just thought the drivetrain location was related to nautical tradition. The starboard (right) side of a boat or ship relates to where the rudder was traditionally located prior to centerline rudders coming into fashion. Same for having the steering wheel and controls on the right side of the car (at least in the UK and most Commonwealth contries plus Japan and a few others). I hadn't considered bolt rotation or mounting a horse for battle in Arthurian times. Excellent video again from GCN.
This is the sort of content that's brought me back to GCN!
I've never questioned the fact the drivetrain is on the right hand side - but even more weird, my track bike is left hand side and I've literally never noticed it 😂
That's hilarious 😆
2:23 I’ve always wondered why pedals and BB are reversed. It seemed counterintuitive. This helped answer that question. I’m so glad you are independent again. I’m actually enjoying your content. I was getting sick of all the sponsored infomercials.
How is bb reversed? 🤨
I just commented on this actually, I don’t believe there is any benefit to a reverse thread on the left pedal, the pedal rotates on a bearing, so there is no force on the thread at any time -in my opinion
@@kalijasin yes. The common English thread is reverse-threaded on the drive side.
@@daztastic147 there's a force on the threads that screw the pedals to the cranks. And because of the different rotation directions that's why one is clockwise and the other is anticlockwise.
I read somewhere that, due to bearing reliability issues in the early days of cycling, the threads were such that the pedals would unscrew in the event of a seized bearing. The rider would be more likely to control and stop the bike in this scenario than have their clipped-in foot injured as it’s pulled around by the pedal.
I’m not 100% convinced of this to be honest, but…
motorcycles similarly nearly always have the chain on the left. i think this is because the brakes are operated by the right hand (front brake) and right foot (rear brake), and traditionally the rear brake was a drum-type design that had a mechanical linkage to the pedal actuator. by placing the chain on the left it cannot interfere with the brake. additional head cannon: kick stands all lean a parked bike to the left, and i think this was intentional to keep the chain (which requires lube & care) sheltered out of the weather as much as possible.
It's the effect of *precession* that tightens pedal axles and English-threaded BB cups.
The video implies BB bearings push the outer cup in the opposite direction of axle rotation. If that were true, that force would act to *accelerate* the motion of the axle. We could use bearings as motors!
99% of bikes have their drive on the right hand side with a few exceptions, some BMX's, track bikes and mountain bikes ....and that road bike in the Eurosport advert interlude video.
Love the nerdy stuff, more please.
Something I've always wondered, especially after a nasty crash on my mountain bike, is why the derailleur points down putting it closer to the ground and in range of rocks etc
Surely the derailleur spring tension would be sufficient to stop the chain from sagging if it was redesigned to be flipped to point up.
Or am I missing something totally obvious to why it's not possible?
The RD is positioned downwards because it's the load-free part of the chain (only tensile forces come from the RD spring). Flipping the RD to the top would cause several problems, as all the loads would then travel through the RD, cage, spring, etc. You wouldn't even be able to use a spring, as any force would just deform the spring instead of driving the bike forward. Additionally, shifting would become much more difficult-you would always need to freewheel to shift, and any force on the pedals would make it impossible. You’d also need beefier RDs and cages to withstand the forces, and there would be efficiency losses due to deformation of these parts. While you could theoretically make the chain cross between the chainring and cassette to flip the RD, that would lead to even bigger issues
I knew about why it's on bicycles that way, and why UK traffic is RHD (and why most of rest of world - other way, because chosen at times and with predominant other type of transportation, eg. carriages, not horseback riding) .. but didn't knew bits why thread is dominantly right. Interesting. Enjoyed.
Love this, a deep dive into the pointless, it's brilliant
There are also some velomobiles who have half right, half left, and even one which has it right, but on both sides at the rear (driving two wheels)
...and there you have it. Why it has never dawned on me is troubling. Fun! Thanks.
That's a deep dive into the topic! Well done!
I have a French-threaded steel frame.
When I first got it, I would tighten the bottom bracket mercilessly.
Then daintily pedaling down the road, I would feel, then see, the bottom bracket . . . slowly unscrewing!
That proved why French-threaded pedals, got everyone scratching their heads, until The British-threaded pedals solved it.
French-threaded bike engineering, one of the many things the French got wrong.
French get everything wrong!
Time carbon, look pedals, mavic wheels, Renault F1 cars, airbus, the Eiffel Tower, Concorde, the sewing machine, the hot air balloon, high speed trains and the metric system. Here you go.
@@l.d.t.6327 Mavic R-Sys - nuffsaid, Concorde, banned from the sky -nuff said, forcefully over-feeding ducks nuff said, etc etc. Now I never said they NEVER created anything. All I deed was mention an aspect of bike threading they fked up. That's all.
@@savagepro9060 nope, I read your comment, and it’s denigrating / xenophobic towards French. It says more about you and your lack of respect. Ps: I’m not even French, but have friends everywhere and a bit less toxic when commenting.
@@l.d.t.6327 what can I say . . . To Itch His Own! Let's hope this was not . . . Talk-Sick? Oh but my Franco-Samaritan Friend, Fight! Fight! Do not surrender the . . . Little White Flag
Grest video, Connor! I knew that you usually approach a horse from the left-hand side but not why. I just thought that you always do it from the same side because horses are used to it and get nervous if you try it on the other side. 😅 If you then do the same with bikes it is more practical for a classic bike stand if the chain drive is not in the way but I guess in the beginning thought about that.
nobody* thought about that.
@@kaischroeder4473 Thanks, I'm having my first cup of coffee and needed the explanation.
I thought it was for the bike vault
Ollie has some competition! Well done Conor!
BTW, some very early safety bicycles did indeed have the chain drive on the left. This was before right hand chain became a standard.
Well done research and explanation, loved it.
"...is it because the Earth spins in a counter clockwise direction?..." ???
Really? Have you considered the fact that the Earth's rotational direction depends on where it is being observed?
And if it actually influences "handedness" why is the dominant handedness not different in the north and south hemispheres?
I don't get what you mean. Earth still rotates in the same direction regardless of which hemisphere it is observed from. If the sun is used as a reference point, it rises in the east and sets in the west, regardless of one's position on the globe. (I think. My brain is starting to hurt).
Where would the observer need to be to see it differently?
The drivetrain on bicycles is always on the right due to historical standardization, ease of use for most right-handed people, and better access to the mechanical components for maintenance.
I have an old Bianchi mb that has it on the left. It is my favorite winter training bike. Love the physics in this though.
3:10 No! This is not accurate. The reason for this reversal is called precession, it has nothing to do with the ball bearings. It is more like the threads roll around slightly as the load direction changes. For a quick demo: If you hold a pencil loosely in your fist and wiggle the end around in a circle the pencil will twist the opposite direction. This applies to both the bottom bracket and crank threads, which is why the both tighten in the opposite direction that they turn.
Whatever the theory, both pedals and bottom brackets will actually loosen if not tightened up enough.
Whatever the reason, it’s the one standard that the entire bike industry can agree on, please, let’s keep it that way. I don’t want to have to worry about buying a left/right side cassette or derailleur
BMX has had the LHD option since the late 90s.
It would also make sense to have it on the same side as your dominant foot, as that's probably the side where most torque will be applied. Also re swords, your left hand will also likely be holding a shield (unless you're rich enough to have a squire to pass it to you after mounting), and that would be very awkward to swing over the horse.
Tandems commonly have their transmission on both sides.
Pedals are actually trying to unscrew themselves as you go, rather than tightening. The left pedal has a reverse thread so that it accomplishes this. I think it is a safety feature: if the pedal seizes, it will then unscrew itself from the crank rather than separate your foot from your leg.
That's only half the answer though. Threads aren't a perfect, precise fit, and pedal threads undergo precession relative to the crank as you pedal under load. The threads are designed to tighten with respect to that precession.
Don't forget the bearings in the pedal. Just like the bottom bracket.
I used to have a left hand drive BMX. I loved it because it stood out.
Lovely video Connor! Well done!
And motorcycles are usually on the left! I get a kick out of that! I mount a moto from the left and a bicycle from the right out of habit wierdly
Well done, very interesting video! Thank you!
This seems to make sense until you realize that virtually all motorcycles have their transmission on the left side
Well that makes sense in the same way -> you step up on the left -> so the hot exhaust should be on the right. And you want to separate your chain and exhaust, hence the chain should be on the left. You do however need to change the screw threads.
Maybe cuz the kick starter is on the right. To utilize limited space options.
Used to agree but you would be surprised how many now have drive on the right.
Hold on, kick start? Haven’t seen one on a new bike for 40 years
On most motorbikes the drive chain is on the left side. The rear sprocket is bolted on and the front fits in slits in the axel. They are not hold by thread around the axel at all.
The reason the first "treads" where right handed is also because the first screws where from wood and wood is stronger left handed, which is the force applied to the wood when using the screw. That is also the reason old windmills rotate counter clockwise.
why is wood stronger left handed? Is this the chirality which is part of whole nature?
@@Long_Toe Science is not sure why wood is stronger is one direction as the other. It is probably a combination of sun and wind. Western wind is much more common.
You learned me something. It seems I didn't know everything (until now) 😁
Thumbs up
The rotational force on the pedals loosens the thread for the same reason the BB is tightened by rotational forces. How can you make a wrong statement and then immediately provide the perfect explanation for why you're wrong? However, the loosening isn’t an issue because the rotational forces are close to zero due to the pedal bearings, but saying the opposite is just incorrect. If you want to test this, the next time you unscrew your pedals, simply hold the pedal axle in place and turn the cranks forward to quickly unscrew the pedal.
Back in the early days of bicycles the left pedal kept coming loose so they changed it to a left hand thread. It has to do with the way the thread bites as the compression force works its way around during pedal rotation.
It was demonstrated to me that it is the effect of mechanical precession.
You can see how this works by putting a water bottle inside of a roll of painters’ tape. Now roll the bottle around the inner surface of the tape roll, and you can observe how this reverses the direction of the force.
At a micro level, the pedal axle is actually walking in the opposite direction around the inner surface of the threaded hole in the crank arm.
First of all, the effect he showed for the rotational forces shows that the torque on the static bearing race actually goes against the rotation. The right pedal spins counter clockwise relative to the cranks, so per his explanation the torque would go clockwise, tightening the thread. So that is actually consistent.
Secondly, look up mechanical precession on wikipedia, that is the actually dominant effect and the explanation why pedals don't unscrew while riding. From extensive experience with unicycles assembled wrong, I can tell you that there is enough torque on the pedal threads while riding to unscrew pedals if you reverse the thread directions.
@@Finnspin_unicyclesPrecession is correct. But the bearing description in the video is also wrong; if the bearings have the slightest amount friction, they will exert a force that is in the same direction as the moving part. If the opposite were true, bearings would act as motors😊
Imagine a world, where there was no consensus about the correct side of the drivetrain. We could have endless discussions about which side is better and the industry would want to make us believe we all need two bikes for each discipline, one with a lefthand side and one with a righthandside drivetrain. 🙄
That was very interesting. Thank you for this new, to me, knowledge.
Anti-clockwise followed by counter-intuitive gave me a giggle.
Anti- and Counter- are similar prefixes. We use Counter-Clockwise in the States vs. Anti-Clockwise.
Interesting - I enjoyed this explanation.
This is a thing in photography, with the lenses you can change on a camera body. The direction the rings turn to adjust focus, aperture, and in some cases zoom changes based on who manufactured the lens. Annoying to go from one system to another if you aren't used to that. And it also comes from proprietary pieces. The mounting system changes, how far away the lenses are from the sensor/film (flange distance) changes, mechanical and electronic linkages change. It's a mess. Be glad there is a standard that everyone uses, and there can't be engineering pressure to make it proprietary. Bottom brackets are annoying enough.
Interesting Connor! Always wondered about the drive train being in the right. But,… why are front brakes in the Uk on the right (and back in the left) and they’re the ‘wrong’ way round in Europe. Scares me every time I’ve borrowed a bike on the continent and pulled the ‘back’ brake
Interesting. Another reason that we drive on the left that I've come across is that in the days of horse drawn carriages, coaches and wagons, the drivers and waggoners had whips with which to encourage greater efforts, (a practice now rightly outlawed because of cruelty) because of dominant right handedness, the whips would need to be raised away from low overhanging branches and more to the middle of the road where the tree branches were at their highest.
I don't know about that. People in my country are still using carriages and whips and they drive them on the right side without any issues
Was wondering this myself couple of days ago :)
Seen a couple of lefty fixies in Miami, although that was quite some years ago.
99% of motorcycles have the final drive chain on the left hand side. 🤔
the kickstart is on the right and more power in the right foot.
There are notable and rather common exceptions: the aircooled Harley Sportsters (they might usually have belts though, not an HD expert, but the same principle), Buells which used the Harley engine, the classic looking modern Triumphs (Bonneville, Speed Twin, Speedmaster, probably forgetting something) and the KTM LC-4 series (edit: and the small BMW GSes). At least. Don't know exactly why these makes have ended with the right hand drivetrain, especially the Triumph, I though it would be because of "British tradition" but quickly image-searching it seems that all the classic British bikes from 50s-70s had a left hand chain, including the original Bonnevilles.
Drivetrains on motorbikes were primarily influenced by the engineering constraints of crank rotation, transmission design, and the cooling advantages of mounting the engine with exhausts forward.
Maybe because its motor operated
100% of motorcycles do not have a threaded rear freewheel
Earth only spins in a counterclockwise direction if you assume the north is the upside.
A couple of billion years ago when all the continents were in the southern hemisphere - the Earth's spun clockwise! It was a pain in the ass to convert all those bicycles to right hand drive back in 3B BC !!! 😂😂
Nicely done. I enjoyed they.
Great expalantion. Any chance you can explain why the front and rear brake lever location on the bars varies with which side of the road we drive on? Also, on motorcycles the front brake is always on the right.
very well done!
Nice one! What's stopping the globe from being depicted 180 degrees offset vertically? In that case the world would spin clockwise. Great science, can't believe I wasn't already subscribed!
Nice content for my next boring birthday amusement talk!
What would throw me off if it moved to the left is when bike is in stand , turning drivetrain hand and going through gears hand would swap.
The bike on the video clip that follows the tv adverts on bike racing is left hand drive. They've shown this for as least 3 years. I can't believe that the TV producers haven't picked up on it.
I'd figure the main reason is the same as why sugar is all right-handed.
Which ultimately boils down to why most wine bottles have dimples at the bottom, even if the wines have no use for them.
@2:25 Nope. This is the exact opposite. Pedal direction makes it looser. I've always been told that it's because the alternative would be pedals that you can never remove.
But just think of when you have a 15 wrench, you basically "pedal" to remove the pedal.
It's the brain.
If you ride a bike, a horse, a scooter etc all of us will get on it from the left side.
The brain also feels safer in left turns. Nearly all races go counter clickwise.
The chain is dirty. Therefore on the opposit side.
And it is it not (and was never) impossible to manufacture left handed threads. ;-)
You don't know my wife... She will get on from any old side
Mind sharing more about the left turning thing? Interesting...
Love this content ♥️
Not all early safety bicycles had the drivetrain on the right. Eg the Ivel was on the left
Very Interesting!
I’ve never understood why pedal/crank arms have a reversed thread for the left-hand side. The fact that there is a bearing arrangement in the assembly means that there is never a force on the thread in either direction, demonstrated nicely by holding the left pedal by hand and spinning your crank backwards, if there was any possibility of this loosening the thread there would be resistance
A hangover from the days of poor bearing quality. A seized bearing would result in the pedal unscrewing instead of pulling the rider’s foot around and causing an injury. So I read once, anyway.
From extensive experience with people assembling unicycles wrong, I can tell you with certainty that pedals do infact unthread if you put a right hand thread on the left and a left hand thread on the right pedal. Look up mechanical precession. You are right, the bearings produce little torque, mechanical precession does (and it goes against the turning direction of the pedal).
@@Finnspin_unicycles why don't fixie riders pedals unscrew when putting back pressure? why don't bmx riders pedals unthread when riding fakie? the answer lies in proper torque of the pedal. if your pedal is torqued properly it will never un thread. "Mechanical precession can occur when too much clearance exists between a shaft and a bushing, or between the races and rolling elements in roller and ball bearings". This doesn't apply to threaded connections. Threaded connections are designed to use the stretch of the bolt as a "spring" which holes the part in place. due to this "spring", there is a constant force applied to hold the pedal to the crankarm, and the very small vibrations that pick up through the ball bearings rolling is not enough to overcome the tension of the spring and break it loose. It requires a certain breakaway torque which cannot be applied in small amounts over time or it will never actually rotate the thread.
However, if the pedal is loose to begin, there will be mechanical precession between the pedal thread and the crankarm thread, which will allow the pedal to back out as no spring tension is holding it.
@@bmxscape While properly tightening the pedals down helps, if you look at pedals, you will find that unlike proper bolts most have barely any flange. In some softer aluminium cranks, you might not even be able to get the necessary preload to fully prevent precession. Preload can also get lost by deformation of the thread or crank due to load spikes (riding down curbs for example).
If properly designed for it, you are right, you can avoid such problems in threaded connections, but a century or so ago, the bike industry decided to go with opposing threads instead. Given that such parts are often changed by the end user who doesn't know how to properly tighten things, maybe it is not such a bad choice.
@@bmxscape Yep when the unicycle was mentioned above the first thing I thought of was fixies.
Connor, if your "Earth's rotation" theory holds, does that mean that creatures evolved in the southern hemisphere are predominately left handed?
I'm cross lateral, ie right handed left footed (I start off on the bike with my left foot on the pedal) so should I have a bike with the transmission on the left?????
Do you know how to make the rotation of the weel backwords?
I mean to revers the bicycle
bonus points for saying octopuses and not octopi. just wondering if this was a pre video water cooler discussion beforehand . lol
The sword sound effect was very necessary, I almost wasn't sure what you were explaining without it.
It's a shame that swords don't actually make that sound when drawn... (source: I own a sword and scabbard)
Amazing nerdy video
It actually never crossed my mind but now I want to know.
i ride LHD for bmx cuz i grind on my right so i dont have to worry about my chain snapping/damaging my sprocket
1:03 WHAT ARE YOU DOING MATE?? ARE YOU OUT OF YOUR MIND??
good work
it's often on the left on Eurosport cycling trailers - but that might be a video flip.
I'd love to see someone make a video explaining why motorbike drive chains are on the left side.
On a fixed speed bike with a single cog you can flip the rear wheel over, swap the left/right cranks and move the chain from right to left, doubling the life of the chainring and cog since the chain then uses the sections of the teeth that previously did nothing.
I don’t think you can put the Cassette on the other side on most bikes.
@@kalijasin Indeed you cannot, the freehub would then be in the wrong direction. This applies to a bike with a fixed cog on the rear wheel, that cannot freewheel. I've seen it done and it does double the life of the components.
Drivetrains on Street BMX bikes can come on either side depending on what side the rider wants it on for grinding or other personal preferences.
I was waiting for the comparison with motorcycle transmission, which is mostly on the left)
Oh! This is an exciting opportunity for the marketing guys at the mega bike companies. Conjure up some explanation of an “improvement” (that most riders don’t need) and put out some ads showing the cool guys riding it and bam! One of the last uniformities of the industry can be crushed. Oh, oh, oh!! And then promote that LH drivetrains work even better with yet another variant of chains that are 1/8” different in pitch!!! Oh my, opening up many new forced obsolescence opportunities!
It's funny because it's true
Great video! Way better stuff then the next how to climb a montain faster video or something like that.
That the transmission is on the right is now very good.
With E-bikes it looks better and makes it more easy to mount the electric motor in the bike.
THe only bike I know that has an chain on the left side is the tandem. Although the sprocket on the rear wheel is on the right.
Very amusing.