Three quarters of all Germans now live in the city, and parking space is becoming scarce even for bicycles. Corridors, balconies and cellar compartments are increasingly the biotope of stationary bicycle traffic - but the bikes have to get there first. The more compact the bike, the easier the journey. Compact bikes, such as those shown in this test, are around 20 to 30 centimetres shorter than a standard trekking bike, making it much easier to negotiate the bends in stairwells. Some also have easily swivelling handlebars or folding pedals to take up less space when standing. However, the main feature of this type of bike is 20-inch wheels, the classic folding bike size. In terms of riding dynamics, they differ noticeably from the usual wheel size: the small wheels develop less gyroscopic force. This makes the steering less stable, but at the same time facilitates acceleration. Small wheels have a slightly higher rolling resistance than the usual "28 inch" wheels and run rougher over obstacles on the road. It is therefore not without reason that larger wheels have prevailed for most purposes - even on mountain bikes in recent years.
But 20-inch wheels are a comparatively good compromise between space requirements and riding characteristics. Two of our test bikes (the I:sy and the very similar Räderwerk Twenty) also roll on extra-thick tyres, which partially compensate for the disadvantages of small wheels. These two and the Cannondale Hooligan proved to be robust city runabouts.
The models from Gios and Dahon are characterised by a completely different approach. They are close to the trendy Japanese toy called the "mini bike". These tiny bikes quote the look of classic sports bikes, but caricature it with their small wheels. The fact that the fashion aspect plays a role here can also be seen in the equipment. With their simple drive components, the relatively inexpensive mini speedsters cannot seriously compete with "big" trekking bikes. However, their riders are sure to attract a lot of attention - and where can you find as many people as in densely populated cities?
The complete article was published in Trekkingbike issue 4/2015. You can read the entire issue in the Trekkingbike app (iTunes and Google Play) or order the issue in the DK shop.
You can download the individual articles as PDF files here.
