Rather than having a full anulus as in a normal inner-tube the Cobra is a stright length of tubing sealed at both ends with a small loop allowing the both ends to be joined into a circle at the valve point. I was not aware of the product before, but in hind sight it is really obvious and goes to show how one’s thinking can easily be limited by just doing things the way they have always been done.
The following video on Vimeo demonstrates the tube changing process.
While designed for BMX, Flybikes supply many BMX components, it is not clear in what sizes the tube is available besides the 20″ 406 standard BMX wheel size however, since many velomobiles use this size, it should be possible to fit the tube to several models. It is interesting that Organic Transit explicitly recommend the use of a “Cobra or similar” tube for the ELF rear wheels which appear to be 26″.
Some questions remain as to how the tube performs both in the short and long term but assuming you can source a tube in your wheel size it would still be a good idea to keep one and a pair of scissors in your velomobile emergency kit.
If any readers have any experience with this or similar inner-tubes please let us know via the comments below.