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.
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
Love geeky historical content.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?
The combination of pedals with a motor is where the term "mo-ped" comes from. Eventually the requirement for usable pedal drive was dropped, leaving only limits on maximum speed and power to be classified as a moped for road-tax and licence purposes.
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.
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.
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.
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.
This video revives discussions I last had in the 1970s, when I was a student. As far as I recall, the common feeling with my friends was that because the safety bicycle was invented in the 1880s in the UK, where we drive our vehicles on the left, other countries supposedly just copied what was already deemed to be accepted practice in order to avoid having to set up a manufacturing supply chain for components for a left-hand drive chain. Back in the 1880s, the UK was still a world superpower (difficult to believe now!) and what we did in this country had more weight than it does now. When I hired a bike when on holiday in France, it suddenly occurred to me that it was potentially a bit more dangerous mounting a bike from the left-hand side on a busy road. My mitigation was to either get on the bike where there was a lowered kerbstone or in a side street. That was okay for a few days on holiday but more problematic if I had lived in France full-time.
Being left handed I always assumed that having the chain on the right side was for the benefit of right handed people. When you ever need to pick up your bike, carry it on your shoulder, using your dominant right hand, the dirty gear is away from your body
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.
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.
When I was 8, I asked my cowboy uncle why we get on the horse on the left side. He explained the horses are trained to be mounted on the left and could become uncomfortable and do something unexpected if we tried to mount them on their right side. He also explained the Indians mounted their horses on the right side. Again because that is how the horses were trained. It seems when the Spanish released the horses in America they forgot to include the training manual that described the left sided was the side to mount your horse. The horse does not care so much except it likes consistency.
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. 🙄
If I were to design a new bicycle, I'd look at what's existing and attempt to improve it. I see no advantage to switching sides, so I'd look at other things and leave the drive where people expect it to be, and save the effort to engineer something new. "Why fix it if it ain't broke?"
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 😂
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.
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.
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.
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.
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.
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…
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!
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
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.
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.
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 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.
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.
What I find interesting is how it is in motorbikes: There is a split and it is based on whether the engine is transversal or longitudinal (i.e. whether the crankshaft rotates along the left-right or front-back axis). Transversal engines have the drive predominantly on the left, while longitudinal used to have it on the right. (In the last 10 years, many big manufacturers still making bikes with those engines switched to the left.) Now in the latter there may be a factor, as they are usually shaft drives and shaft always turns in a certain direction depending on what side it is, which may be used to counteract the engine tilting the bike during acceleration and deceleration, so the choice of the side is bound to the choice which direction the engine rotates in. This is not a factor in transversal engine with shaft drive as the shaft is the only thing rotating on front-back axis. The choice of left for transversal engine is interesting. Unlike bikes, the rear sprocket is usually mounted with multiple screws but the (small) front one has usually just a single one. Also, the drive needs to transfer not just accelerating forces but also decelerating ones from the wheel to the engine (gearbox). Maybe it's just as someone mentioned, early motorbikes were bicycles with engine mounted, two separate drive trains, transversal was the default choice thanks to parallel rotation axis and since the bicycle drive was on the right, the motorcycle ended up on the left, considering the rear sprocket was not bound by the same considerations about rotation and the bike one. What's also interesting is the fact side stands on both bicycles and motorcycles is nearly universally on the left. Which is the worse side for 2/3 of the world who ride on the right as they have to mount/dismount from/to the side of traffic. (Personally I do not find either side better or worse if the bike is in a neutral position, although leaning it towards you makes mounting and dismounting easier - and you cannot do that on most motorbikes due to their weight being too much to hold, unless they are on the side stand.) The only exception is trials motorcycles which use opposite side from the drive train and as that is mostly on the left, their side stand ends up on the right.
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?????
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!
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
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
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.
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.
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.
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.
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 !!! 😂😂
"...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?
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.
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😊
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 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.
When you stop your bike, as a right handed person, you put your left foot on the ground because it's easier to start the bike with your right leg. If the chain was on the left it would touch your leg when you lean the bike.
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.
@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.
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.
you forgot that, because of the right hand threads being mass produced it becomes extremely expensive to get the left hand threads crafted for pretty much "no apparent reason". so unless you custom order, or make every single bolt by hand yourself, to make the bike, or get the bike made, to uniformly apply physics in the opposite direction you'd be safer just buying a standardized bike. or just put a bearing wash behind every bolt and you'd probably be as safe as your standard left pedal.
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.
Ive never thought of it. But without watching the video, i would guess it's because all gear components are made facing the same way, so it's just easier.
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
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
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
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.
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
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?
The combination of pedals with a motor is where the term "mo-ped" comes from. Eventually the requirement for usable pedal drive was dropped, leaving only limits on maximum speed and power to be classified as a moped for road-tax and licence purposes.
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.
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...
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.
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! 💚
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
@petermacdonald6377 not in the beginning, though. I'm over 50, too, and don't inspect motorcycles for that stuff.
This video revives discussions I last had in the 1970s, when I was a student. As far as I recall, the common feeling with my friends was that because the safety bicycle was invented in the 1880s in the UK, where we drive our vehicles on the left, other countries supposedly just copied what was already deemed to be accepted practice in order to avoid having to set up a manufacturing supply chain for components for a left-hand drive chain. Back in the 1880s, the UK was still a world superpower (difficult to believe now!) and what we did in this country had more weight than it does now.
When I hired a bike when on holiday in France, it suddenly occurred to me that it was potentially a bit more dangerous mounting a bike from the left-hand side on a busy road. My mitigation was to either get on the bike where there was a lowered kerbstone or in a side street. That was okay for a few days on holiday but more problematic if I had lived in France full-time.
Being left handed I always assumed that having the chain on the right side was for the benefit of right handed people. When you ever need to pick up your bike, carry it on your shoulder, using your dominant right hand, the dirty gear is away from your body
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.
Archimedes was a standout left midfielder for the Greek National Team
He played in that position on principle.😀
could/would watch videos like this for hours, ty all
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.
When I was 8, I asked my cowboy uncle why we get on the horse on the left side. He explained the horses are trained to be mounted on the left and could become uncomfortable and do something unexpected if we tried to mount them on their right side. He also explained the Indians mounted their horses on the right side. Again because that is how the horses were trained. It seems when the Spanish released the horses in America they forgot to include the training manual that described the left sided was the side to mount your horse. The horse does not care so much except it likes consistency.
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. 🙄
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
If I were to design a new bicycle, I'd look at what's existing and attempt to improve it. I see no advantage to switching sides, so I'd look at other things and leave the drive where people expect it to be, and save the effort to engineer something new.
"Why fix it if it ain't broke?"
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 😆
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.
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.
Finally someone acknowledges the historic/ equestrian reasons! 🤩
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.
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.
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.
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…
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!
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
1:03 WHAT ARE YOU DOING MATE?? ARE YOU OUT OF YOUR MIND??
When I try mounting my Scultura from the right my sword always get stuck in the frame somehow.
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.
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.
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 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.
Well done research and explanation, loved it.
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.
You learned me something. It seems I didn't know everything (until now) 😁
Thumbs up
Lovely video Connor! Well done!
Love this, a deep dive into the pointless, it's brilliant
...and there you have it. Why it has never dawned on me is troubling. Fun! Thanks.
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)
Connor Attenborough 👍👍
That's a deep dive into the topic! Well done!
Ollie has some competition! Well done Conor!
What I find interesting is how it is in motorbikes: There is a split and it is based on whether the engine is transversal or longitudinal (i.e. whether the crankshaft rotates along the left-right or front-back axis). Transversal engines have the drive predominantly on the left, while longitudinal used to have it on the right. (In the last 10 years, many big manufacturers still making bikes with those engines switched to the left.) Now in the latter there may be a factor, as they are usually shaft drives and shaft always turns in a certain direction depending on what side it is, which may be used to counteract the engine tilting the bike during acceleration and deceleration, so the choice of the side is bound to the choice which direction the engine rotates in. This is not a factor in transversal engine with shaft drive as the shaft is the only thing rotating on front-back axis.
The choice of left for transversal engine is interesting. Unlike bikes, the rear sprocket is usually mounted with multiple screws but the (small) front one has usually just a single one. Also, the drive needs to transfer not just accelerating forces but also decelerating ones from the wheel to the engine (gearbox). Maybe it's just as someone mentioned, early motorbikes were bicycles with engine mounted, two separate drive trains, transversal was the default choice thanks to parallel rotation axis and since the bicycle drive was on the right, the motorcycle ended up on the left, considering the rear sprocket was not bound by the same considerations about rotation and the bike one.
What's also interesting is the fact side stands on both bicycles and motorcycles is nearly universally on the left. Which is the worse side for 2/3 of the world who ride on the right as they have to mount/dismount from/to the side of traffic. (Personally I do not find either side better or worse if the bike is in a neutral position, although leaning it towards you makes mounting and dismounting easier - and you cannot do that on most motorbikes due to their weight being too much to hold, unless they are on the side stand.) The only exception is trials motorcycles which use opposite side from the drive train and as that is mostly on the left, their side stand ends up on the right.
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
BTW, some very early safety bicycles did indeed have the chain drive on the left. This was before right hand chain became a standard.
Nice. But does the Earth rotate in a counterclockwise rotation? Seems to depend on your point of view!
From the point of view of the hemisphere where the majority of people live, it rotates in a counterclockwise direction.
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!
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.
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
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.
Very educational. I’ve learnt a fair bit today.
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.
You didn't see the track bike used by the Japanese team in the Paris Olympics? Or the one used by the US team in 2016?
You didn't pay attention did you.
I thought it was for the bike vault
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.
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.
Seen a couple of lefty fixies in Miami, although that was quite some years ago.
Well done, very interesting video! Thank you!
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
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 !!! 😂😂
That was very interesting. Thank you for this new, to me, knowledge.
5:09 Stock footage company couldn't afford to hire full class of students.
😂
Love the video every day should be a school day.
Love this content ♥️
"...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?
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.
I used to have a left hand drive BMX. I loved it because it stood out.
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😊
Great video! Way better stuff then the next how to climb a montain faster video or something like that.
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.
Why do eurosport show a bike with it on the left on their ads for upcoming cycling programmes?
Freestyle bmx come in left or right side drive.
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.
When you stop your bike, as a right handed person, you put your left foot on the ground because it's easier to start the bike with your right leg. If the chain was on the left it would touch your leg when you lean the bike.
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
Love this video
@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.
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)
Interesting - I enjoyed this explanation.
GCN Does Science: The channel we may not deserve, but definitely the channel (the nerdy) want.
very well done!
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.
Wow, very interesting; thanks!
Tandems commonly have their transmission on both sides.
Nicely done. I enjoyed they.
you forgot that, because of the right hand threads being mass produced it becomes extremely expensive to get the left hand threads crafted for pretty much "no apparent reason".
so unless you custom order, or make every single bolt by hand yourself, to make the bike, or get the bike made, to uniformly apply physics in the opposite direction you'd be safer just buying a standardized bike.
or just put a bearing wash behind every bolt and you'd probably be as safe as your standard left pedal.
Was wondering this myself couple of days ago :)
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.
i ride LHD for bmx cuz i grind on my right so i dont have to worry about my chain snapping/damaging my sprocket
Ive never thought of it. But without watching the video, i would guess it's because all gear components are made facing the same way, so it's just easier.
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.
Very Interesting!