Downhiller ARC8 prototyp 00111

Testing to the extreme

The Craft Bike Days powered by DT Swiss are back, and this year we brought something special. The reaction from Mitch (Editor, was priceless when he found out what bike we brought. Yes, we've been working on a downhill bike. Why? Find out here.

First and foremost, we're not claiming to create the perfect downhill bike right off the bat; rather, it's a development project from which we expect a lot of information, and it's our first aluminum prototype of a downhill bike.

After successfully incorporating our Dual Pivot Suspension technology into the production of the Evolve FS and Essential, where the system proved itself in practice and in numerous magazine tests, we took the Slider technology a step further.

The advantage of this type of linkage is that the slider corresponds to an infinitely long lever, approaching the perfect linear-progressive characteristic. Both the Evolve FS and the Essential already benefit from this kinematics.

However, in theory, the Slider Technology offers the greatest advantage with a lot of travel. So, why not take it to the "extreme"?

Et voilà: here is "Einstein."

Downhiller ARC8 prototyp 00379

But if we're already daring to create such a bike, we want to test more than just the slider. For this, removable plates are mounted on both sides. These water-jet parts are interchangeable and can be produced in various versions. This allows for the independent variation of various parameters such as kinematics, travel, and geometry.

Downhiller ARC8 prototyp 00388

For example, if you want to change the travel, you position the slider higher or lower. The progression can be changed by the angle of the slider. The flatter it is turned, the more linear the response, and the steeper, the more progressive. Moreover, the anti-squat could be varied, or using an additional pulley, pedal kickback could be reduced.

Downhiller ARC8 prototyp 00400

In the realm of geometry, both the chainstay length, bottom bracket height, and rear wheel size can be varied using the side plates.

To change the reach, the attachment points of the side plates can be moved forward or backward. For an adjustment of the head angle, the attachment points would need to be rotated around the front wheel axis.

Downhiller ARC8 prototyp 00393

And if that's not enough, it could even be converted to a completely different suspension system, such as High Pivot or VPP.

The current version has a travel of 200mm and the following key geometry specs:

  • Head angle: 62.5 degrees
  • Reach: 465mm
  • Stack: 622mm
  • Chainstay length: 450mm
  • Bottom bracket drop: 25mm

But, as mentioned, all of this can be adjusted through changes to the side plates.

Björn Aeschlimann from Dead Rabbit in Switzerland manufactured the bike.

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