7 ms·

Tricycles are inherently unstable in turns, especially when not loaded down, because they cannot lean. And when carrying a load, the same rules of physics apply

Tricycles are inherently unstable in turns, especially when not loaded down, because they cannot lean. And when carrying a load, the same rules of physics apply, resulting in a lot of torsional forces on the frame. There's a reason we see so few of those on the roads, amidst an explosion of various human-powered modes of transport. Here's the original: http://youtube.com/watch?v=RuPwRQOUhl4 http://youtube.com/watch?v=RuPwRQOUhl4 Here's the reimagined modern version: https://www.youtube.com/watch?v=kA7qGYNFuY0 https://www.youtube.com/watch?v=kA7qGYNFuY0 In both cases, the rider effectively sits atop of where the handlebars would be on a traditional trike. You can see in the first video the lads have a hard time keeping all wheels on the ground. One notable difference between the new model and the old is that they seem to have changed the geometry of the frame so that the driver doesn't lean into the turn (the turning wheel stays upright). They don't demonstrate it in motion very well, but that kind of turn action will tend to throw the rider "out" of the turn, making the trike fall over opposite of the direction of the turn. The old version tends to fall "into" the turn. I can't think of many advantages to this design, other than the driving unit and cargo are modular. Even then, the rider would not be able to travel without the cargo portion. Trikes are tricky, they don't go very fast, they don't turn well, and they're wider than most other pedal-powered vehicles, making them hard to use on existing cycle infrastructure.

djmips 1y ago
Using a video of duffers trying the bike for the first time is not very convincing. I expect that with experience you'd get the handle on the trike design and control it quite well.
econ 1y ago
If you have a large preferably rusty box in front of you the cars treat you like royalty.
jandrese 1y ago
If you're trying to keep all of the wheels on the ground you're not using it efficiently. With trikes when you go around a curve the inner wheel lifts off the ground, especially as many trikes have solid rear axles. It feels scary to have it pitch outward in the turns, but it is how the machine works.
- 0_____0 1y ago
  What makes this true of trikes but not of the typical automobile?
  - mtreis86 1y ago
    They do. Volkswagens from the 80s and 90s that have solid dead rear axles "tripod" around corners.
  - jandrese 1y ago
    Automobiles have 4 wheels. The geometry of the situation is very different. This is also why cars have differentials, because otherwise the car would be fighting against the turn. Basically when you turn your trike turns into a bike.
  - 00N8 1y ago
    Some cars like the Mini Cooper S do lift a rear wheel when turning sharply under braking -- I've seen this a lot in autocross racing. I normally only see front engine/FWD cars with limited suspension travel do it though. Trikes are less stable & will lift a wheel more easily overall.
  - enragedcacti 1y ago
    The principle is the same, the distinction has more to do with suspension (or lack thereof) and the solid rear axle. The same strategy of lifting the inside rear tire is used in competitive go-kart racing: https://youtu.be/cMAtgPX6st8?t=312 https://youtu.be/cMAtgPX6st8?t=312 . If the carts had a differential then it would be a different story (and they would be cars and not karts according to the SuperFastMatt taxonomy)
- layer8 1y ago
  Isn’t it the outer wheel that would lift off the ground?
  - jandrese 1y ago
    You would think so but no. The inner wheel is the one that lifts.
cpgxiii 1y ago
> There's a reason we see so few [tricycles] on the roads, amidst an explosion of various human-powered modes of transport. Perhaps in the US and western Europe, but tricycle tuk-tuks and cycle rickshaws are extremely common in other parts of the world.
- TrueGeek 1y ago
  In The Netherlands 3 wheel bikes are fairly common to haul kids and dogs. I can easily get mine on two wheels if I take a sharp, fast, turn - but after you do it once you learn the limits and it's a very stable bike.
  - deleted 1y ago
    [deleted]
  - clan 1y ago
    Same in Denmark. It is almost a must have for inner city families. Much more common than two wheel Long Johns. Two very common models are: https://www.christianiabikes.com/classic/ https://www.christianiabikes.com/classic/ https://www.ladcyklen.dk/ladcykel/nihola-ladcykler.html https://www.ladcyklen.dk/ladcykel/nihola-ladcykler.html
    - cycomanic 1y ago
      The common aspect is that both the Netherlands and Denmark are flat. The danish/Dutch trikes are really just unsafe when you pick up significant speed like down a hill. I am a long time cyclist, who raced for years. I've never felt as unsafe on a bike as when I tried riding and a fast bike speed on a Christiania.
      - bgnn 1y ago
        Luckily cargo bikes aren't for speeding and racing but for carrying cargo. It would be like using a truck to race instead of a mid-engine super light sports car. Durch cargo trikes are generally assumed safer than their two-wheeled alternatives here.
asveikau 1y ago
I see the word "tricycle" and I'm reminded of the Piaggio MP3, from the parent company of Vespa. It has two front wheels and one rear.
- WaitWaitWha 1y ago
  It is the Velorex that pops into my head.
SoftTalker 1y ago
The instability in turns was what made the "Big Wheel" fun when I was a small child. Too low to the ground to really tip over but easy to make it spin out. I had a conventional tricycle too, don't recall ever falling over on it, though it could get tippy. You learned to lean to offset that.
steanne 1y ago
there are trikes that can lean. this is one, and not the one i remember see an article on a few years ago, so there's at least two companies out there doing it. https://youtu.be/9LwqIIqysZ0 https://youtu.be/9LwqIIqysZ0
somat 1y ago
Yes, the tricycle. Masterfully combining the exposed position of a bicycle with the space requirements of a car. They really don't make sense in motorcycles, A large part of the point of a motorcycle is that you are willing to give up a lot of comfort and safety in exchange for having a very small nimble personal transport. Nothing wrong with this tradeoff, but why would want a vehicle that takes up the same amount of space as a car that gives you the safety and comfort value of a motorcycle?
- skeeter2020 1y ago
  I personally set aside the safety & comfort sacrifice of the motorcycle but cannot accept the performance loses. Similar to when I see people maneuvering a bicycle over rough or varied terrain while sitting down; you might as well be driving a car.
  - kennywinker 1y ago
    Might as well be driving a car… well, except for the climate impact, cost, maneuverability, and pedestrian death toll.
- turbosepp 1y ago
  My uncle always said: "those things combine the weaknesses of a motorcycle with the weaknesses of a car"
- kennywinker 1y ago
  At the speeds you can go on this, motorcycle is a bad comparison. Depending on the rear module used, this could definitely use most of the bike infrastructure in my city without a problem. There’s already a bike delivery company that uses e-trikes to great effect moving goods around the city center - in the downtown core 35kph keeps up with traffic 85% of the time, so taking the road is also an option.
cycomanic 1y ago
Yes when my kids were young I tried out a bunch of cargo bikes and the christiania trikes feel so unnatural and unsafe it's really hard to describe. I still ended up with a trike but it's a leaning one which feels just like a normal bike (and it's very narrow so fits through doors into backyards...). This is what I got: https://chike.de/en/ https://chike.de/en/ it was the best purchase I ever made! For anyone thinking about a cargo bike when having small kids; go ahead your kids will love it, you will love it!
gcanyon 1y ago
Of course the guys find the old one tippy: there's no load in back. Put even twenty pounds on that platform and stability would be wildly improved.
seanhunter 1y ago
> There's a reason we see so few of those on the roads, amidst an explosion of various human-powered modes of transport. Cargo/passenger trikes are growing in popularity here where I live in London. I see probably a dozen a day which are an even mix of people ferrying kids about in a Danish/Dutch style "bakfiets" thing (you seem to be able to get 1-4 small people in the front of one of these depending on how picky they are about being squashed in) and cargo/parcel delivery which seem to be more modernized designs anecdotally. Whereas the model for a courier company used to be a person on a bicycle or motorbike doing one delivery at a time it seems more and more to be shifting to a person on a cargo bike doing multiple related deliveries in an area, and somewhat competing with traditional logistics just with a faster turnaround. The hook for parents seems to be if you have more than one kid it's still possible to use a bike to get around rather than a car (which is a very inconvenient mode of transport within London generally) and it's much faster and with bigger range compared with trying to get your offspring to walk (which might not even be possible for any kind of reasonable distance depending on age). The advantage to these designs is that you have a bicycle that can carry cargo. Having decided that is the criterion you want to hit, having a modular version may well be beneficial. The disadvantage you cite (that the driver can't lean) really doesn't factor too much into this use case because they aren't trying to travel at speed. Urban settings have much more stop-start movement in straight lines than cornering, and if you think about a parent with kids in the front of a bike they probably aren't trying to go super fast because they want to know they can definitely brake fast if the need arises.
Moldoteck 1y ago
fyi there are trike designs that can lean. Their two wheels are leaning on turns: first google result https://newatlas.com/butchers-and-bicycles-mk1-leaning-cargo-trike/30526/ https://newatlas.com/butchers-and-bicycles-mk1-leaning-cargo... but there are many more models able to do it

djmips 1y ago

Using a video of duffers trying the bike for the first time is not very convincing. I expect that with experience you'd get the handle on the trike design and control it quite well.

econ 1y ago

If you have a large preferably rusty box in front of you the cars treat you like royalty.

jandrese 1y ago

If you're trying to keep all of the wheels on the ground you're not using it efficiently. With trikes when you go around a curve the inner wheel lifts off the ground, especially as many trikes have solid rear axles. It feels scary to have it pitch outward in the turns, but it is how the machine works.

0_____0 1y ago
What makes this true of trikes but not of the typical automobile?
- mtreis86 1y ago
  They do. Volkswagens from the 80s and 90s that have solid dead rear axles "tripod" around corners.
- jandrese 1y ago
  Automobiles have 4 wheels. The geometry of the situation is very different. This is also why cars have differentials, because otherwise the car would be fighting against the turn. Basically when you turn your trike turns into a bike.
- 00N8 1y ago
  Some cars like the Mini Cooper S do lift a rear wheel when turning sharply under braking -- I've seen this a lot in autocross racing. I normally only see front engine/FWD cars with limited suspension travel do it though. Trikes are less stable & will lift a wheel more easily overall.
- enragedcacti 1y ago
  The principle is the same, the distinction has more to do with suspension (or lack thereof) and the solid rear axle. The same strategy of lifting the inside rear tire is used in competitive go-kart racing: https://youtu.be/cMAtgPX6st8?t=312 https://youtu.be/cMAtgPX6st8?t=312 . If the carts had a differential then it would be a different story (and they would be cars and not karts according to the SuperFastMatt taxonomy)
layer8 1y ago
Isn’t it the outer wheel that would lift off the ground?
- jandrese 1y ago
  You would think so but no. The inner wheel is the one that lifts.

cpgxiii 1y ago

> There's a reason we see so few [tricycles] on the roads, amidst an explosion of various human-powered modes of transport. Perhaps in the US and western Europe, but tricycle tuk-tuks and cycle rickshaws are extremely common in other parts of the world.

TrueGeek 1y ago
In The Netherlands 3 wheel bikes are fairly common to haul kids and dogs. I can easily get mine on two wheels if I take a sharp, fast, turn - but after you do it once you learn the limits and it's a very stable bike.
- deleted 1y ago
  [deleted]
- clan 1y ago
  Same in Denmark. It is almost a must have for inner city families. Much more common than two wheel Long Johns. Two very common models are: https://www.christianiabikes.com/classic/ https://www.christianiabikes.com/classic/ https://www.ladcyklen.dk/ladcykel/nihola-ladcykler.html https://www.ladcyklen.dk/ladcykel/nihola-ladcykler.html
  - cycomanic 1y ago
    The common aspect is that both the Netherlands and Denmark are flat. The danish/Dutch trikes are really just unsafe when you pick up significant speed like down a hill. I am a long time cyclist, who raced for years. I've never felt as unsafe on a bike as when I tried riding and a fast bike speed on a Christiania.
    - bgnn 1y ago
      Luckily cargo bikes aren't for speeding and racing but for carrying cargo. It would be like using a truck to race instead of a mid-engine super light sports car. Durch cargo trikes are generally assumed safer than their two-wheeled alternatives here.

asveikau 1y ago

I see the word "tricycle" and I'm reminded of the Piaggio MP3, from the parent company of Vespa. It has two front wheels and one rear.

WaitWaitWha 1y ago
It is the Velorex that pops into my head.

SoftTalker 1y ago

The instability in turns was what made the "Big Wheel" fun when I was a small child. Too low to the ground to really tip over but easy to make it spin out. I had a conventional tricycle too, don't recall ever falling over on it, though it could get tippy. You learned to lean to offset that.

steanne 1y ago

there are trikes that can lean. this is one, and not the one i remember see an article on a few years ago, so there's at least two companies out there doing it. https://youtu.be/9LwqIIqysZ0 https://youtu.be/9LwqIIqysZ0

somat 1y ago

Yes, the tricycle. Masterfully combining the exposed position of a bicycle with the space requirements of a car. They really don't make sense in motorcycles, A large part of the point of a motorcycle is that you are willing to give up a lot of comfort and safety in exchange for having a very small nimble personal transport. Nothing wrong with this tradeoff, but why would want a vehicle that takes up the same amount of space as a car that gives you the safety and comfort value of a motorcycle?

skeeter2020 1y ago
I personally set aside the safety & comfort sacrifice of the motorcycle but cannot accept the performance loses. Similar to when I see people maneuvering a bicycle over rough or varied terrain while sitting down; you might as well be driving a car.
- kennywinker 1y ago
  Might as well be driving a car… well, except for the climate impact, cost, maneuverability, and pedestrian death toll.
turbosepp 1y ago
My uncle always said: "those things combine the weaknesses of a motorcycle with the weaknesses of a car"
kennywinker 1y ago
At the speeds you can go on this, motorcycle is a bad comparison. Depending on the rear module used, this could definitely use most of the bike infrastructure in my city without a problem. There’s already a bike delivery company that uses e-trikes to great effect moving goods around the city center - in the downtown core 35kph keeps up with traffic 85% of the time, so taking the road is also an option.

cycomanic 1y ago

Yes when my kids were young I tried out a bunch of cargo bikes and the christiania trikes feel so unnatural and unsafe it's really hard to describe. I still ended up with a trike but it's a leaning one which feels just like a normal bike (and it's very narrow so fits through doors into backyards...). This is what I got: https://chike.de/en/ https://chike.de/en/ it was the best purchase I ever made! For anyone thinking about a cargo bike when having small kids; go ahead your kids will love it, you will love it!

gcanyon 1y ago

Of course the guys find the old one tippy: there's no load in back. Put even twenty pounds on that platform and stability would be wildly improved.

seanhunter 1y ago

> There's a reason we see so few of those on the roads, amidst an explosion of various human-powered modes of transport. Cargo/passenger trikes are growing in popularity here where I live in London. I see probably a dozen a day which are an even mix of people ferrying kids about in a Danish/Dutch style "bakfiets" thing (you seem to be able to get 1-4 small people in the front of one of these depending on how picky they are about being squashed in) and cargo/parcel delivery which seem to be more modernized designs anecdotally. Whereas the model for a courier company used to be a person on a bicycle or motorbike doing one delivery at a time it seems more and more to be shifting to a person on a cargo bike doing multiple related deliveries in an area, and somewhat competing with traditional logistics just with a faster turnaround. The hook for parents seems to be if you have more than one kid it's still possible to use a bike to get around rather than a car (which is a very inconvenient mode of transport within London generally) and it's much faster and with bigger range compared with trying to get your offspring to walk (which might not even be possible for any kind of reasonable distance depending on age). The advantage to these designs is that you have a bicycle that can carry cargo. Having decided that is the criterion you want to hit, having a modular version may well be beneficial. The disadvantage you cite (that the driver can't lean) really doesn't factor too much into this use case because they aren't trying to travel at speed. Urban settings have much more stop-start movement in straight lines than cornering, and if you think about a parent with kids in the front of a bike they probably aren't trying to go super fast because they want to know they can definitely brake fast if the need arises.

Moldoteck 1y ago

fyi there are trike designs that can lean. Their two wheels are leaning on turns: first google result https://newatlas.com/butchers-and-bicycles-mk1-leaning-cargo-trike/30526/ https://newatlas.com/butchers-and-bicycles-mk1-leaning-cargo... but there are many more models able to do it