The Arc8 makers drew the first lines for this mountain bike in 2016 - it was to be an aggressive trail bike: Very efficient on the climbs, but much better downhill than you would expect. However, it was not intended as a cross-country race bike. Its creators were all the more skeptical when the bike was nevertheless used in cross-country racing. So the founders Serafin Pazdera and Jonas Müller inadvertently created a great cross-country bike. The question to themselves was obvious: "How good could a mountain bike be if we developed it specifically for this purpose?"

The answer to their own question was "make". The result is the Evolve FS, Arc8's interpretation of a cross-country bike with 100 to 110 millimetres of travel at the rear and 100 to 120 millimetres of travel at the fork.

A true lightweight

Arc8 claims a frame weight of 1240 grams - incredibly light. To achieve this, a lot of time was invested in the carbon construction and more than fifty different layups were analyzed with the help of laminate tools, which would not have been possible with physical prototypes.

Although this is the net weight, the painted frame with shock and guide system also only weighs an impressive 1780 grams in size L. The complete bike weighs just 9.5 kilograms in size M and in the XX1 configuration.

Not new - but unique

Arc8's new suspension system, which in principle is not actually all that new, catches the eye. Arc8 replaces the bellcrank with a slider system that is small, light and stiff, but results in an almost perfectly linear-progressive suspension curve. Many are familiar with a similar system from the Yeti 303R or a more recent example, the Trek Supercaliber. The Arc8 slider system is therefore not entirely new, but it is definitely unique in the cross-country segment.

Radical geometry

The geometry of the Evolve FS frame is rather unusual for cross-country use. Frame size and fork length do make a difference, but based on an L-frame with a 120 mm suspension fork, the steering angle is 65 degrees, which is in the range of steeper enduro bikes. The wheelbase and reach are relatively long at 1234 and 495 millimeters, but the chainstays are again quite short at 430 millimeters. Combined with a short stem, this results in a very smooth ride with direct steering behavior, while the short chainstays ensure that you are still agile out of corners.

Details

Almost as much attention has been paid to the frame details as to the rear triangle and co. For example, the frame has an aero down tube, which not only offers less surface area for the wind to attack, but also less surface area for dirt to stick to.
The frame also offers space for two water bottle holders, which is particularly interesting for marathon riders and other long-distance riders.

Prices and availability

The Arc8 Evolve FS is available as a frame kit including the Fox "Float DPS Performance" shock for 3499 francs. The complete bike with Sram XX1 Eagle AXS is available for 10,499 francs, while the Shimano XTR version costs 9199 francs. The cheapest option is the XT version for 6499 Swiss francs, which at 10.7 kilograms is by no means anything to hide. The bikes and frame kits are now available in sizes M and L (body heights 160- 178cm and 178- 190cm) from specialist retailers.

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