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.
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.
There's even a rear steering cargo trike company in Denmark. It's weird but I had an explanation that it was meant for low speed and maneuverability with cargo rather than as an exercise machine or high speed transportation.
I've ridden a few trikes like you'd use for a small food stand and they aren't so bad to drive around. Would I take one mountain biking or on a hill climb? No, but that's beside the point. I also don't use my phone for all my CAD work.
I rode something like this as part of a tour in switzerland, when turning left I was told to lean to the right (which is obviously different to a two wheeler where you lean in the direction of the turn), otherwise you'd pop-up on two wheels easily enough!
And you really have to push the handle bars, for steering. Again, very different to a two-wheeler.
>when turning left I was told to lean to the right (which is obviously different to a two wheeler where you lean in the direction of the turn), otherwise you'd pop-up on two wheels easily enough!
Can you explain the mechanics behind that? When turning left, wouldn't the bike be at risk of tipping to the right? Wouldn't leaning to the right make that worse?
That document says you need to lean into a turn. That's what I would expect. Turn left, lean your body left. The picture on the cover shows the rider turning left and leaning left.
>Since sidecar outfits are not symmetrical, the technique for left turns is somewhat different from right turns. The outfit won't lean into the turn like a "solo" bike, but instead rolls slightly towards the outside of the turn like an automobile. The sidecar driver compensates by leaning body weight towards the turn and by applying extra force to the handlebars.
Leaning in on a two wheeler is rolling the frame to the left further.
That same frame roll/tip on a trike causes the right wheel to leave the ground. In order to counter act that, and essentially prevent the frame from rolling/tipping at all in the turn, is to move your weight to the right so that wheel stays grounded.
If you really push and try you can get the left wheel up on a left turn but it’s more effort than popping a wheelie on a two wheel bike. It’s hard to do on accident.
I would guess it has to do with the direction of force changing, the left and rear tires getting closer and the right and rear tire distance getting farther and what that implies regarding the distance each wheel needs to travel in the turn.
Edit: maybe tilt is a better word than roll and tip, basically putting the frame less upright is what I mean by that
I imagine the two wheels being in the back and the driver positioned relatively high from the ground makes for very different turning mechanics in OP's linked bike though?
The only "trike-like" bicycles I see are used by elderly people, everything for cargo/kids is either two wheels or three with two wheels in front.
With these probably taking up even more space, where do people keep them? (Living in a German apartment complex without a garage I can stow away some normal bikes, but if just 10 families in this 40-unit house had one of those... oof)
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.
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.
It's not racing, but if there's a steep hill you will pick up some speed (it doesn't help that Christiania uses drum brakes not disk brakes). Also the whole point of a bike is that it's faster to go around than walk. Don't get me wrong I'm all in on cargo bikes and I used a cargo bikes for my kids in a hilly area for years (it was a leaning trike see my other post for what kind it was), but the trikes with the joint in the middle are just unsafe (yes I've also seen people tip over with them, and it really only requires a sharp turn where you have to accelerate a bit).
Before rolling over and killing and maiming the people on board, which is actually a good example of what would happen if one tried to race a racing bike with a Christiana-like cargo bike.
No they are not popular in the Netherlands. Easily 90% of cargo bikes are two wheeled, because tricycles are really only for novice/disabled cyclists. Going above say 20km/h is just plain dangerous with a tricycle, definitely not stable at higher speeds in even the most gentle curve
There are a couple of advantages of tricycles that go beyond novice/disabled. They don’t need a kickstand, so they’re easy to park when loaded. They don’t need balancing at stops. They generally have better load capacity.
There’s also tricycles which can lean into a corner which makes them similarly agile as two-wheeled bikes. They’re still wider, though.
Trikes are certainly not for long distances and a sporty style, but as a short distance cargo/kids hauler, they’re cheap, reliable and effective. I know quite a few people
Who are happy with them.
Three wheel motorcycles are popular amongst bikers who get too old to handle a two wheeler. Some have two wheels in front, one in back, and look almost like cars, others are just a standard motorcycle chassis fitted with two rear wheels.
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/ 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!
> 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.
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?
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.
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.
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.
The problem is that trikes don't steer with countersteering. When you transition to one wheel lifted, you have a brand new mode of operation with a misaligned rear wheel.
If they're not drive why connect them at all? Why not have them mounted independently and eliminate the need for an extra part? My only real guess is it's easier for carrying capacity.
I suspect it because with a single piece axle the torsion forces trying to twist the wheels into negative camber are taken by the axle and the forces on the two wheels negate each other, leaving the frame to only have to deal with vertical linear force.
Maybe. You can get the same effect by putting two bearing on the inside of the wheel with a disconnected axel I think. A simple axel might come out cheaper than that though.
it's the inner wheel with a tilt/lean. Your weight has to get out over the COG to balance. The feeling ranges from foreign to terrifying and I'm not sure why you wouldn't just go with an excellent cargo bicycle that avoids the entire issue.
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.
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 . 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)
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.
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.
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.
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.
Here's the original: http://youtube.com/watch?v=RuPwRQOUhl4
Here's the reimagined modern version: 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.