If you compare the measurement data of the new American racing file with its predecessor, the Superfly FS - which has been completely cancelled for 2016 - the geometry data reads almost identically, apart from minor deviations. Only three points stand out: the slightly longer top tube, the head tube shrunk to 100 mm and the almost two centimetres shorter chainstays. In terms of frame weight, the new Top Fuel chassis (2262 g) with its aluminium chainstays has even gained 300 grams. A step backwards? No, because at 75.9 Nm per degree, the Top Fuel is significantly stiffer, more direct and more manoeuvrable than the Superfly FS. The sensitive rear triangle also achieves better values in terms of efficiency. We were impressed by the excellent rear suspension function: very sensitive on rough gravel, progressive enough for smaller jumps and not too firm in between. This allows the 110 millimetres of travel to be fully utilised. Our test bike only lacked the necessary liveliness when accelerating - despite the latex milk in the Bontrager tyres, the wheels weigh too much for this price class. Whether the Top Fuel with its Sram 1x11 groupset is the right choice for marathons and stage races depends on your own physique and the route profile. You'll also have to make do with a large water bottle (maximum three-quarters of a litre). The smaller frames may only hold half a litre.
Test summary of the Trek Top Fuel 9.8
Stiff, efficient and equipped with a super chassis: The Top Fuel has what it takes to win the World Cup. The downside: the lightweight top models are very expensive.
PLUS Stiff, robust frame, drive-neutral kinematics, sensitive chassis
MINUS Heavy wheels, poorly equipped compared to the price
You can read this article or the entire BIKE 10/2015 issue in the BIKE app (iTunes and Google Play) or buy the issue in the DK shop reorder:
