Sixpack Evo Rail Ultra saddle review (148 g)

The Sixpack Racing EVO Rail Ultra is an extremely lightweight saddle distinguished by its innovative one-piece construction. The one-piece, fibre-reinforced shell also forms the patented integrated rail system with a 7 × 10 millimetre profile, eliminating superfluous material and reducing weight to a minimum without sacrificing stability.
The clever part of the rail system is that it fits any top-clamp seatpost with 7x10 mm dimensions and can simply be slid in from the front with the clamp slightly open.

The saddle is available in two widths: 140 mm and 160 mm, with Sixpack quoting 148 g for the 140-mm version and 150 g for the 160-mm version, each with a tolerance of ± 2 grams. The saddle has an overall length of 246 millimetres, creating a compact shape that stays out of the way on descents and does not interfere during trail and enduro use.
A generous layer of E-TPU padding provides comfort, distributing pressure evenly while keeping the overall weight low despite the thicker cushioning material. The textured upper provides grip on contact. A central relief channel helps distribute pressure more evenly. The underside of the saddle also features an integrated M5 mounting point for accessories.

There is not usually much to say about installation in a saddle review, but the Sixpack EVO is a very different matter. Depending on the seatpost, fiddling the rails into the clamp is often unavoidable; the EVO, by contrast, slides into place within seconds, made possible by the open rail at the rear of the saddle.
One advantage its creators do not highlight at all is that the rail is quite long, allowing the saddle to be moved a very long way forwards or backwards in the clamp. If you are suffering from an overly slack seat angle, for example, this lets you compensate by several degrees and shift the riding position towards a steeper effective seat angle. My own ageing e-bike is just such a candidate, and I now have nothing left to complain about in that respect.
The fact that its weight approaches that of far more expensive ultralight saddles is a welcome side effect.

Above all, however, a saddle has to do one thing: remain pain-free on short rides as well as long ones. When you sit on the Sixpack Racing EVO Rail Ultra, you can feel your sit bones, though far less than with some other saddles that focus the pressure particularly strongly and precisely on them. Even after several hours in the saddle, I was spared painful pressure points; on some rides I did not think about the saddle at all, which is a good sign. Sitting can naturally become a little uncomfortable at times, but the contact area is large and wide enough to make it easy to adjust your position on the saddle. I found my favourite spot quite far towards the rear. Initially, I would have liked the saddle to have a small ramp at the back for additional support. Ultimately, however, I did not miss this feature.
The padding is slightly thicker than on some other sporty saddles, but feels firm and clearly defined. During the review, the material never compressed to an uncomfortably hard point. You can read how this works for riders in different weight categories – particularly heavier riders – in NoSane’s impressions below.

Asked whether the Sixpack Ultra could be the one saddle for everyone, however, my answer is no. My girlfriend concluded after only a short time that this saddle was not for her. In fairness, I should add that she does not get on with several other saddles either, because choosing the right saddle is always a highly individual matter.

As far as I am concerned, the Sixpack Racing EVO Rail Ultra has made it into my personal top three saddles. Where exactly it ranks, and whether I might even use it permanently on all my own bikes, is something I will decide over the coming months – the fact that it has reached this point at all should make it abundantly clear how impressed I am by this innovative saddle.