The Christiania cargo bike
humansinvent.com
humansinvent.com
It is true they are becoming more popular lately though. And there are many different brands in the Netherlands selling them, even with electrical drive support. http://babboe.nl , http://bakfiets.nl , http://fietsfabriek.nl , even the old brand Gazelle is jumping into the fray: http://www.gazelle.nl/collectie/stadsfietsen/specials/2013/c...
(edit: The article is very specifically about the Christiana cargo bike. Sadly there's not much detail about it's development.)
http://www.christianiabikes.com indicates 30 years for this particular iteration.
These things are terribly hazardous. You can't ride them in the road as they are too wide and most of the drivers are assholes and will try and kill you at the first available opportunity.
That leads to the owners riding them on the pavement which is even more hazardous as they have zero stopping power, huge momentum and take up the entire width meaning people have to dive into the road when one appears (see asshole drivers above).
I really want these sort of things to succeed. In fact I think the best form of transport is a recumbent tricycle. But I don't think they work in most poorly designed cities or even most poorly designed towns.
I wouldn't even ride one in Cambridge to be honest.
I found them to be perfectly safe to ride, relatively easy to manoeuvre, with drivers giving ample space (presumably because they think they contain young children, whereas I was just transporting 30KG of alcohol).
They also have disc brakes, and do stop pretty damn well in all conditions.
I guess the only thing I'd modify about a Christiana bike is that I'd want to figure out how to take out the worst of the bumps from potholes. But adding suspension that works on a trike isn't a cheap thing and would not use commodity bike parts... so I can see why they haven't.
But yeah... ride one, they're far more fun they you realise and you're given far more space from drivers than you'd expect.
I got no grief when I rode one of these, and would not call them a hazard.
Maybe it's just the part of London you are in?
The big disadvantages to me is that they get hot which causes the pads to degrade quickly, they weigh more, they're a crap load more expensive and if anything goes snap, hacking it on the road is hard.
From a non-technical point of view, I think discs lock up easier and are the force applied versus the braking force isn't as linear meaning less control.
If you have a heavily loaded bicycle (or tricycle), such as a touring bike with lots of heavy bags or a cargo bike, then you can opt for disc brakes which have additional pistons forming the caliper.
Standard disc brakes have only one piston per brake, but brakes such as the Hope M4 http://www.hopetech.com/page.aspx?itemID=SPG336 have 2 pistons per brake. Which in turn greatly increases the amount of power available to stop the wheel as the pad size is also increased.
Other factors are, as you imply, the rotor size. Small rotors have less stopping power as the same power is transferred to the disc but yet the decreased size requires an increase in power to be equally effective. Small discs are in the order of 160mm in diameter, and the largest are 203mm in diameter.
For the greatest stopping power one would go for 203mm diameter rotors and use the "4-pot" (4 pistons in total, 2 in the front brake, 2 in the rear brake) brake calipers.
Other factors in disc brakes are that the discs can get very hot. Effects of this is that they can deform the shape of the disc.
So also on the market are floating discs, where the braking area is not physically attached to the internal fixing area, hence the term floating... so only the outer area deforms.
And you can also get vented rotors, which are made of two braking areas separated by air to increase the surface area by which the rotors can cool. They tend to also be floating.
So disc types:
1) Standard single piece of metal, can deform with extreme heat
2) Floating disc, less deformation with heat: http://www.hopetech.com/page.aspx?itemID=SPG312
3) Vented and floating discs, less deformation and reduced cooling time: http://www.hopetech.com/page.aspx?itemID=SPG313
The last factor in disc brakes is the method by which one would brake. Hydraulic gives by far the greater performance over cabled, but there is an outside chance that if you haven't managed the temperature of the disc that the hydraulics can overheat and freeze. It's something you manage and I've not heard it happen in years, even as a myth. Also, cable is easier to maintain.
The result of that though, is that touring bikes tend to go for cabled brakes and of the cabled brakes the Avid BB7 stands out. Everyone else just goes with the hydraulics because it's unlikely they're going to be doing a 25km descent with luggage that could cause such extreme overheating.
What else whilst I dump knowledge...
Why not put the discs on the rims? You're correct that it would be better performance but wheels themselves deform on impact (potholes) and the disc would fight against that and cause problems. Also... rim brakes are actually good enough already, much cheaper and require less of a high tolerance in engineering. That said, the Buell motorcycle company did this and it works well if you can afford it: http://www.totalmotorcycle.com/photos/2006models/2006models-... although you now cannot easily get commodity replacement parts. There is also the issue of weight, and that a large ring of metal isn't just additional weight, but rotational weight which requires greater energy to get moving.
Why do Tour de France style road bikes not have disc brakes if they are so good? Basically the UCI made them illegal, and manufacturers of ultra-light bikes prefer rim brakes as disc brakes require them to strengthen the fork and crown to deal with the extra force involved, and both the calipers and fork adjustments would add weight. That said, you will find discs on a lot of consumer road bikes now thanks to cyclocross pushing the technology.
In summary: disc brakes are awesome and will always stop you, even when it's wet. But only consumer bikes have them, and to make them simple and cheap larger rotors are used with plain discs. Performance discs are vented and floating rotors for long and hard braking periods, and touring people tend to use cables over hydraulic.
And one final thing... mix and match. You'll see professional off-road riders putting large 2-pot calipers up-front on large floating rotors, but then only put a single pot on the rear with a small rotor. The vast majority of braking power goes through the front wheel, and people still obsess over weight to the point of wanting to save a few grams where they can.
This is mainly driven through by cyclists becoming more politically motivated to affect a change.
What it comes down to is segregation of transport types; cars from bicycles; pedestrians from bicycles.
So for better or for worse, merely segregating cyclists isn't enough. Something needs to be done about the asshole drivers.
[Of course, merely as a matter of general principle, something should be done about the asshole drivers, because they are simply bad for society, but that's a long and hard task, which entails both legal and cultural changes.]
I'd love to live in a place where there were either clear delineations (cars/bikes/pedestrians). Failing that, bikes really belong on infrastructure for cars, not infrastructure for pedestrians.
The problem with that 'cult' is that it is driven from a fear that once you provide segregated cycling infrastructure then, you as a cyclist have no right to use roads (Germany has done this).
This is a fallacy that keeps the majority of the population in cars. You need to make the 'perception' that cycling is safe enough for 10 year olds to use to actually enable people to begin cycling.
This is so much more about the general health, well being and safety of the general public than whether you are able to tank it down a dual carriage way while being passed by cars doing 70mph.
I guess my point is that road cycling culture is a chicken and egg problem. If more people of all ages are riding, drivers will be more conscious, and it will be safer. If everyone stays constrained to the walking paths and bike lanes, the utility isn't there ( because the lanes and paths don't go where you want ), and the drivers get to stay oblivious.
Finally, your last point about the dual carriageway misses the point completely. Yes, people who like biking a lot are the 'early adopters' who push for more radical social change. For all the reasons I've mentioned, highways are actually very safe: wide lanes, wide shoulders, very little direction changing (no turns, no dooring) and pretty attentive drivers. I'd wager you have less fatalities on highways than congested metropolitan areas, because the drivers are less distracted and overburdened.
The epitome of this is our new 'divided bike lanes', where they stick a curb between you and the car. This has all sorts of features:
- cars completely ignore you and cut you off by turning right without looking. I've already been broad-sided once this year.
- you can't safely overtake other cyclists without cutting out into the roadway (where nobody is watching for you)
- pedestrians treat it as extra pavement and stand right in the bleeding way
As for riding on the pavement, IMO it's never OK on any bike. At least in Ontario (Canada), if a vehicle has brakes it belongs on the street, if it doesn't it goes on the pavement. They could technically ticket people for riding on the sidewalk, but the whole culture that treats riding on the road as needlessly dangerous lets them get away with it.
Good call. Load some groceries or kids on this things, and with the weak (looks like backpedal) brake design I'm seeing here you're asking for a world of trouble once you gain enough momentum from going downhill.
Let's keep in mind these were designed in the Netherlands, where everything is as flat as a pancake. Not always applicable to your average US city.
>In fact I think the best form of transport is a recumbent tricycle
Until you try to go uphill unfortunately.
I agree that these things are incredibly dangerous, I often see mothers with kids in the front (with no helmet) turning out of blind corners. With mother at the back she can't see what round the corner until the kids are well into the road!
that being said, zero stopping power? i used the trike to transport various heavy things (not children though) and the two front disc brakes had no problem stopping me immediately. maybe you just had bad luck with yours?
I do not own one but have ridden one. Compared to my Dawes Galaxy it really just doesn't stop at all. I've been run over by one as a pedestrian as well. It came skidding to a halt. That did have children in it though.
The idea that London doesn't accept bicyclists or provide infrastructure for them is quite untrue. That said, plenty of people in London from Europe view London as insufficiently bike-friendly. Which it is, too.
the two most important things are: - segregated bicycle paths - forgiving attitude towards bicycles by drivers
those should have top priority, the rest is icing on the cake. photo of a bicycle path in copenhagen: https://farm5.staticflickr.com/4119/4735055023_b1b8425c8b_b....
but maybe i am biased. i would give up all the things you mentioned for wide, segregated bicycle paths as i just love a safe and stable ride on my bike.
A hydraulic brake system would be ideal for this application but they are quite expensive.
... Guess that's more a front platform than a front box. Ah well. The bakfiets-bike is still cooler. :P http://goo.gl/lfGq1
http://www.tomscargobikes.com/tomscargobikes.com/BUILD_YOUR_...
There are a lot of cycling groups for parents and small kids. Here's one: http://kidicalmasspdx.org/
So if you want to put the cargo's weight between two wheels and sit somewhere in the center; it's better to have a customized standard frame with saddle in the back to make construction as easy as possible.
A side effect of the cargo weight in front and the drivers in the back is that the load weight per wheel is more evenly distributed.
Also, as mentioned before, it's easier to monitor cargo, kids and your vehicles maximum width in relation to any obstacles in front of you.