You've got to have a lot of spunk to be seen on a bike like this, but it's not just for show – it's been used to deliver sperm to fertility clinics in Copenhagen, Denmark since 2010.
Now the idea has been taken up on the other side of the Atlantic, too, with Seattle Sperm Bank buying their own delivery bike, complete with a freezer compartment to store donor sperm.
The machine carries up to 20 vials of US$500-$600 semen in its liquid nitrogen-cooled tank, which keeps the samples at -120 to -150°C. As with the European 'sperm bike', it's a modified BULLITT cargo bike from Danish company Larry vs Harry. To cope with Seattle's hills, the US version has had an electric-assist kit added.
As well as being a statement of green intent, the bike is seen as a valuable and very visible publicity tool. Good donors are hard to find as, after initial sperm-quality analysis, just five to 10 percent of donors make it to the next stage of a genetic family history interview. Nor is the process helped by declining fertility rates.
BULLITT cargo bikes are a modern take on the traditional Danish 'Long-John' design, using a massively oversized aluminium frame and lightweight components to keep weight under 25kg. They're rated to carry up to 100kg of cargo.
They appear to have achieved something of a cult status and have been used for a number of other unusual uses including mobile sound, mobile bike repairs and even cargo bike surfing. They're available in the UK via www.thebullittbike.co.uk.