Every big person who comes to us brings a story of suffering with them," says Stefan Stiener. He should know: The head of Velotraum measures above normal himself and has therefore always had a sympathetic ear for his fellow sufferers. It is usually only after many years of makeshift and DIY solutions that they decide to put their money where their mouth is and buy a "real bike" - one that finally fits!
The frame sizes of most standard trekking, everyday and touring bikes end around 60 or 62 centimetres. Some manufacturers go up to 64 or 65 centimetres, but that's usually the limit. A person with an inside leg length of one metre still sits on it like a child's bike.
Statistics show that people are getting taller and taller. The majority of the reasons for this are better nutrition, education and medical care - commonly referred to as "prosperity". For some statisticians, increasing height is therefore even considered a direct indicator of a society's level of prosperity. According to a representative survey by the Socio-Economic Panel of the German Institute for Economic Research (DIW), a good 6% of all German men were over 190 centimetres tall in 2006. For women, however, the proportion is less than a tenth of a per cent.
It is still often smaller, dedicated suppliers such as Velotraum or Tout Terrain that build bicycles for this niche audience. Sometimes, as in the case of Stefan Stiener from Velotraum, there is personal motivation at the beginning: if you can't find a decent bike, you end up building one that fits - because you can. However, established series manufacturers also value the really large customers: Fahrradmanufaktur has been faithfully offering the T-XXL for years, Hartje offers two trekking bikes up to frame height 70, and a few other models in 67 and 64. 11 so-called "XXL models" in its Kalkhoff, Raleigh and Univega brands, which also range up to frame sizes 67 and 70, are produced by the quantity giant Derby Cycles. Frame construction companies such as the Schauff brothers or Werner Juchem have even specialised in large cyclists as a clientele. Long cyclists are particularly well catered for by classic custom suppliers with a large proportion of customised bikes such as Maxx from Rosenheim or the Saarland-based manufacturer Utopia: Here, the regular range extends up to frame size 66, at Utopia London even up to 73. Unfortunately, we were unable to organise test bikes from Hartje and Juchem: Hartje was sold out and Werner Juchem was prevented from producing an XXL test frame by a cold.
Big bikes have their own peculiarities: It is not enough to simply increase the size of a trekking bike. This is because the greater loads caused by heavier riders and longer leverage ratios in the frame need to be taken into account. We have known this since Archimedes: If the levers are long enough, you can break anything! The starting point for bicycle design is always the wheels. These are usually 28-inch wheels, which can be made very stable with thick tyres and up to 36 spokes. The stability comes not only from the components such as spokes or rims, but also from the design: built by hand, trued and re-centred, wheels can withstand amazing loads without complaint. Regular re-centring helps to extend their service life. Wide tyres, suitable rim widths and sufficient air pressure create a stable foundation. Clever construction and appropriate tube dimensions play the main roles when it comes to frame material: Large tube diameters provide more stable support than thin ones, and additional struts help to compensate for leverage ratios that become less favourable with increasing length. If the wall thicknesses (sometimes up to 2 millimetres) are also adjusted, the result is a stable frame for tall and heavy riders. The same applies to attachments such as stem, handlebars and seat post: a larger diameter increases stiffness. Seat posts should be equipped with a two-bolt clamp; if a clamping bolt loosens and, in the worst case, breaks, the saddle will not fall off immediately. Appropriate handlebar widths of 66 or 68 centimetres suit taller riders better than narrow 64-centimetre bars. When it comes to suspension forks, air suspension forks are actually easier to adjust. In the test field, however, mostly reinforced rigid forks are used; the two suspension forks on Kalkhoff and Univega are specially equipped with hard steel springs. However, there is a procurement problem here: many manufacturers deliver their suspension forks with fork shafts that are too short: In the giant frames, a standard 260 mm steerer tube does not even protrude from the top of the head tube!
The frame geometry in particular poses enormous challenges for manufacturers: a frame for tall riders must not only be tall enough, but also long enough. We have measured top tube lengths of around 66 centimetres for frame size 70. The head tubes also have to be long enough to avoid leaving the handlebars too low: otherwise there is a risk of knee contact when cornering. We discovered what is probably the longest head tube in the world on the Kalkhoff Image XXL, size 70: A whopping 26.5 centimetres lift the cockpit to a suitable height for an upright riding position. The Suntour CR8 fork fitted here has an extra-long steerer tube - another extra cost for fork and bike manufacturers. The rear triangle length also needs to be adjusted to provide the necessary heel clearance when transporting luggage. Here, however, the seat stays are again steeper than usual. As a result, not every pannier rack will fit on the Giant bike. As you can see: The topic has its pitfalls.
When it comes to crank lengths, you should remember that tall people also prefer long cranks. Shimano still offers XT cranks in 180 mm length - as do other specialised suppliers such as Specialités TA. However, these products are usually more expensive and more complex to procure, so our test field mostly contains 175 mm standard cranks from Shimano, and even a Mighty crank with 170 mm on the women's model from Utopia. But you can't make a science out of it, as Sumo designer Jan Schauff knows. "There are many discussions and individual preferences here, but no absolute truth. Longer cranks on large frames make sense in theory, but over the years you also get to know the complete opposite: In BMX races, 180 mm cranks are nothing special, even for 10-year-olds."
In any case, our test rider Mark Richter was impressed by the professionalism and manoeuvrability of the current giant bikes. "You can immediately feel that the bikes are high quality. That's what I've always wanted: to get on and feel comfortable. Even though I was already over 1.90 tall at 17. But back then, bikes like that simply didn't exist." Today, even tall cyclists have every reason to be very happy, starting from 700 euros upwards.
