Thank you so very much for all of your insight, it has been fundamental in the redesign. Please follow this link to my campaign to build a working prototype, http://www.indiegogo.com/projects/zipcycle .

My Best,

The prospects of the Velotilt are quite impressive. The combination of your drivetrain and the leaning mechanism present a new clarity not yet present in velomobile design. I am curious to know if I could ask you a few questions off line, ebirkhauser@kgpds.com .

Cheers,
Eric

Countless existing examples show you’re wrong. There is nothing positive or stylish about everyone being stripped and/or groped by the TSA in order to fly, but people put up with it because flying has clear advantages over taking a train or driving (in certain situations, for those people). All sorts of terribly ugly cars sold well in the 70s because they got good gas milage during an energy crisis. If someone invented a teleporter that required you to be slathered in bat guano, you can bet there would still be people lined up to crap-zap themselves to the other side of the world.

A focus on style is a bankrupt design. Sure, you’d *want* things to be as appealing as possible, but you need to start with a fundamental concept that is realistic. Your just introduces too many new things to be cost effective, and it retains the same fatal flaws of other failed systems.

If I were to suggest one thing to focus on, it would be the bike. I looked at the world records for recumbents (http://www.recumbents.com/wrra/records.asp) to see what real difference a tail fairing really makes (I expect that’s how your bike would be categorized). In *every* case but the 1 hour time trial, the weight of the fairing seems to slow the bike down, and there is only a negligible gain for the 1H. Even then, you’re looking at a 33mph performance put out by an elite athlete going non-stop the whole distance, which makes your aim of turning a 12mph commuter into someone who can easily see 24mph quite suspect. If you really have good reason to believe your bike can achieve the gains you claim, you should be able to shatter those records.

“For better or worse, walking is an essential component of all forms of mass transit, it is unavoidable.”

Not so. I usually bike to any bus or train stop (when I can’t just bike the full distance faster); in a more lazy world people could take electric scooters or skateboards. But that highlights the key failure of shared systems like this: they offer all of the disadvantages of mass transit with none of the advantages. The push should be to high-speed transit *via* bikes solving the “last mile” problem; walking is no longer an acceptable last mile solution (some super-lazy people will even circle a parking lot just so they don’t have to walk a few extra meters to the store).

“While this concept may be a ways off from our current reality, my aim is to shift the center of the conversation by aiding in the visualization of our potential.”

And that’s a good goal, so long as you keep in mind that most people are not going to approach it from a similarly high-minded perspective. They’re going to want practical benefits, and even if you manage to fool them for long enough to fund a pilot project, the dream won’t last long if it cannot live up to the level of potential you’ve got them expecting.

Honestly, I must admit that I am completely flabbergasted, had I any idea I was going back and forth with one of my heroes, well I suppose I would not have changed my response, but nonetheless I am overwhelmed with gratitude for you time and thoughtful consideration. Your work and innovation has had an enormous impact on my exploration. I hope to continue to have your insight and expertise as my process advances. Again, my deepest thanks for your feedback,

Eric

I have a second model which is fairly similar, but lower. Working on a tilting module for my own two bike to make them into tilting delta trikes and working with a group of people on a new tilting velomobile called Velotilt.

Great to see you back in the forum. A very interesting idea, CFD analysis of a chassis approach on a standard bicycle geometry verses recumbent could be revealing. One that I will look forward to exploring, once I have resurrected this design based on all of this incredible feedback!

Thanks,
Eric

EB “My point is that style becomes a necessity in spinning the notion into an attractive solution in the public mind.”

IS “No, it doesn’t. The first order of business is showing a solution that beats alternatives in reality. Style is an “it’d also be nice” not an “everything” (which you stated emphatically, but have now abandoned for some reason). The fact remains that your making things “attractive” does so in a way that shoots costs through the roof, but doesn’t add much in the way of comparative utility.”

So we may have to agree to disagree, a positive public perception or style is absolutely essential to the success of a product. That being said, you are absolutely correct, it must be qualitatively better, I am working on that!

EB “This concept is not showing a foam back pad, which would be an absolute necessity.”

IS “No, it’d be an absolute deal breaker! Like I said, I have ridden recumbents quite a bit and without a mesh back their seats are just sweat machines. A foam back is just an insulator that worsens the problem. And the streamlined bike itself insures that there will be even less airflow to help cool the rider’s back. It’s a loser; rethink your design.”

Alright, I will give mesh a chance, thank you for your patience and persistence.

EB “But some of these issues have to do with the bicycle and its availability.”

IS “Not many. There are plenty of people (in the US, at least) that buy bikes and just let them sit in their garages. You could probably give bikes away for free, even your super-slick one, to anyone that asked for them and see very little increase in riding. About 0.00% of the issue is solved by having bikes at pay stations you must walk to before you can go somewhere.”

For better or worse, walking is an essential component of all forms of mass transit, it is unavoidable. The best strategy for alleviating these issues is through transit oriented development.

EB “So two things; aerodynamics and electric assist.”

IS “I’m well aware of the fantasy of both, but I’m firmly grounded in reality when I take them into account. Proper aerodynamics take more effort than just a streamlined bike shell, and even then the biggest benefit is at higher speeds. Since your design is not fully faired, I have my doubts that it will be as efficient as you hope (and I also worry about how it would handle in a gusting cross wind, but that’s another issue entirely). So, yeah, someone who rides a lot might be able to push it up to 25+mph on a casual commute, but I have serious doubt that the infrequent 12mph rider is going to see much benefit. I really do hope to be proven wrong on that point, though; build it and we’ll see.

As far as electric bikes go, I have long been of the opinion that current technology is not where it needs to be for bikes. They add too much weight and complexity to the bike compared to what little boost you gain. Your shell is already a highly vulnerable (and likely highly expensive, as well) component of your design, so you’d better think twice before you put a lot of extra weight inside it.

Further, you need to think about this as more than just a bike issue. That is to say, people *already* have the ability to use a two wheeled, powered vehicle to get from place to place at relatively high speeds, both in the form of scooters and (even faster) motorcycles. They’re not using those much as it is, and I doubt they’d be using them more if they had get one at a shared station. At the same time, car shares and rentals are doing OK. You need to incorporate the implications of *all* of that if you really hope to offer alternatives to current transportation models.”

I have developed a membrane fairing for this concept and yes the drag coefficient reduction is substancial ( http://birkhauserdesign.com/blog/2012/9/5/120905-zipbikeprocess ). But from previous feedback on a velomobile concept on issues of ventilation and practicality, I am reluctant to make the fairing an integral component of the share design. I prefer for it to remain an option for private ownership. Nonetheless on the topic of aerodynamics, until a prototype is built, it is all just computer simulation.

Making the assist package purely optional would allow riders of different physical ability to choose added weight and assistance or lighter weight pedal only approaches. An in-hub battery and motor package would allow for system flexibility based on the preferences determined by members. I must stress that the assist would aid acceleration to higher speeds and maintaining said speeds, but a electric assist speed governor is a must, as this would not be an electric motorcycle share strategy. The concerns of safety will make it difficult for any type of motorcycle share program to be successful. With a grade separated infrastructure, the real and perceived safety of bicycle transit systems is dramatically better. Great tip, a study of the Car2Go and zipcar business model will prove helpful in my process.

EB “To be effective stations must be evenly dispersed according to population density”

IS “And that’s why they generally will not work, ever. You can only “share” exclusive resources like this when the density remains relatively constant. If 10 people want to get from the West Bank of the U of MN campus to the East Bank, for example, that would be a viable scenario for sharing, because it would be balanced out by 10 people wanting to go the other way within a short time period. And that is something that will be repeated many, many times throughout the day.

But there is little sharing to be had when you have 100 people who are widely dispersed in the suburbs that want to get downtown, work there for 8 hours, and then expect to be able to get a bike to ride back home again. To get any sharing, you have to haul bikes around by truck (as the local bike sharing system does) to fill the usage gaps, which ultimately turns it into a silly mass transit system for bikes!”

Great point, on the mass transit system for bikes… a humorous one at that. People in areas of higher density will always have better access to mass transit, and can better serve bidirectional efficiency of the system. For the people in areas of low density a longer walk or private ownership is a reality, so the benefits must outweigh the drawbacks. Sadly we do exist in a cultural of denial. The benefits of any mode of active transit from a standpoint of healthcare costs alone is astonishing. That we are complacent with the fact that the leading cause of death in this country for individuals between 3 and 30 is automobile related, is truly incredible.

EB “I think we are all cyclists here in this forum, we have drank the Kool-Aid, so the question I ask is how can we successfully and safely grow our community while enriching the potential of we consider the best way of getting from a to b.”

IS “Sure, and that’s why I like to see any efforts to tackle the problem. But to actually *solve* the problem, you have tackle it with a healthy dose of reality. In reality, grand visions such as these don’t provide people with the small steps that are *necessary* to change their behavior slowly over time. I mean, hell, I can’t even deduct milage for taking a bike somewhere for business, but I could if I rode a damn car! Are there *any* incentives to riding a bike coming out of DC? Property tax rebates? Mandated health insurance rate reductions? If anyone there were really serious about quintupling the biking population, there are so many better ways of doing it.”

You are right, we must crawl before we can walk, but the notion of walking gets us to crawl. In the field of architecture, the challenge is the same. We can design and fabricate buildings that are energetically positive, but without strong incentives we are forced into designing projects just a little bit better than the standard convention. You are absolutely right, it takes serious policy to effect change, but without landmark buildings in the arena of sustainability, the populace has an intense difficulty in accepting that dramatic positive change is possible. If we begin to visualize the true potential of active transit systems, it can gain traction in the public mind. While this concept may be a ways off from our current reality, my aim is to shift the center of the conversation by aiding in the visualization of our potential.