It's really awesome how much effort is put into testing and presenting these designs! They actually made the product to hold and observe and if you've ever designed and built something it is such a cool feeling to have your design to hold in person. I can't wait to see how they present and test the frame ideas...

Also, for people worried about issues with gears and disk brake on the same side, it has already been done on production bikes. My friend has an Eastern Nightrain with those parts mounted on the same side and has no issues. A picture: http://velospace.org/files/IMG_20120103_153204.jpg

pperini, the tagline about symmetry is just a fun way to describe the design. It is something of an inside joke beyond that, but I'm sorry you seem to be offended by it. This design is a first draft, something that wouldn't be presented to the public if a company was developing it because all the problems have not yet been worked out. You and others are providing feedback that will be addressed if this were to go any further into design. As with any radically different design there are many things that must be taken into account and adjusted, such as the spacing issues you discuss, before physical testing begins. Beyond that, on my page there is a list of comments about the design and proposed changes. In that list I say that I ran out of time to to develop the connecting/stiffening bar on the rear end. I did not want it to be a simple block when the rest of the tubes are so flowy and that takes time to model.

That is something to consider in a future revision, this is just a first draft for me. Thanks for the feedback!

So what's the situation with chain growth? I don't fully understand the effects of suspension/pedal feedback/pedal bob as a result of chain growth but I believe bikes with extreme rearward wheel paths such as this have issues resulting from pulling on the chain through suspension travel? I'm not hating, just want to know.

-About dirt or grease on the brakes, I propose a motocross style shield on the rotor. The caliper would need to be either supported on an extension of the axle or easily releasable for removing the wheel for service. -The caliper would be able to pivot out and away to remove the wheel. This plays into the benefit that the wheel can be quickly swapped or worked on. -Extra short chainstays are possible if the standard chainstay and/or seatstay bridges are removed because the wheel can be tucked in closer to the frame. -An internal gearbox would be ideal for this bike, I didn't build it in because of time constraints even though it was my initial intention with the design. That would draw comparisons to Ducati motorcycles as it would seem like a transmission is wedged in a bike frame, which is cool. Don't deny it.

I think a lot of people have the same questions so I will address them in a post at the top. Comment if you have anything you would like to know. Remember, this is a first draft prototype, not everything you see here would be the same in production. -My initial "plan" was to have a vertical support member in the rear triangle, but I ran out of time to implement it. This would help stiffen the rear triangle. -On a note about stiffness, larger than average bearings would be used at the rear triangle connection to support the load. With a properly designed linkage and frame pivot, the shock would not experience any larger than average torsion loading. See below... -About the off-axis forces on the shock, etc... the frame is strong enough to absorb most of the force, but consider what happens when you hit a bump while cornering? There is a non-axial force on the shock and it is asked to compress and it does the job just fine. The force is going through a linkage in both my design and any commercially available designs. The difference is the frequency of those twisting forces, so the linkage/frame connection have a longer than average fatigue life. As noted above, strong linkage and pivot are what is needed.

Perhaps you can explain how galvanic corrosion and crevice corrosion apply in this situation? As I understand, this process occurs under presence of an electric potential. This can be from an applied source or occuring naturally in highly salty environments such as the ocean where a current is induced. If the bike is not stored in this environment how would this process happen? Also, wouldn't a simple sprayed protectant on the inside of the tubes be enough to stop this, not a barrier between materials?

You are correct, but I would say a higher precision bearing would need to be used to solve that problem. 1 for the price of 2? Haha, I also considered the cross-over but that was a time hang-up and it gave me a unique benefit of increasing room for the rear wheel so extra short chainstays are possible.

I think a lot of people have the same questions so I will address them in a post... -My initial "plan" was to have a vertical support member in the rear triangle, but I ran out of time to implement it. This would help stiffen the rear triangle. -About the off-axis forces on the shock, etc... the frame is strong enough to absorb most of the force, but consider what happens when you hit a bump while cornering? There is a non-axial force on the shock and it is asked to compress and it does the job just fine. The force is going through a linkage in both my design and any commercially available designs. The difference is the frequency of those twisting forces, so the linkage/frame connection have a longer than average fatigue life. -About dirt or grease on the brakes, I propose a motocross style shield on the rotor. The caliper would need to be either supported on an extension of the axle or easily releasable for removing the wheel for service. Thanks for the comments everyone!