1. THE ORIGINAL CONDITION
Specialized Stumpjumper Comp, 4299 euros, 14.03 kilos (photo above)
The Stumpi has already outgrown the trail category, but even with 150/140 millimetres of travel it offers a perfect starting point for long tours. Despite the SWAT box in the down tube, the full carbon frame weighs just two kilos without the shock, making it one of the lightest in the all-mountain category. In our last test, we only criticised the rather high weight and the somewhat sluggish handling on the climbs. Perfect for our tuning project.
2. THE TRANSFORMATION
Budget:
818 Euro | Weight: -1404 grammes
1 wheelset 1488 g / 698 Euro
Many a carbon wheelset would struggle with this weight. The Newmen Evolution X.A. 25 wheels come with aluminium rims that have a rim width of 25 millimetres and were even very dent-resistant in the last wheel test. The new generation of hubs is also more user-friendly thanks to the elimination of bearing adjustment. The wheelset alone weighs 713 grams less than the Roval Traverse wheels.
2 tyres 795 / 758 g / 100 Euro
When new, the Specialized rolls on its own 2.6 inch wide tyres. In combination with 29-inch diameter tyres, the weight settles at a hefty 987/947 grams. For a tyre of this width, the Butcher/Purgatory combination rolls surprisingly well, but has little grip. The Schwalbe Fat Albert Front and Nobby Nic tyres in a width of 2.35 inches save 381 grams, roll fast and can even improve on grip. However, due to the smaller volume, you have to ride them with a little more air pressure, which is not a problem with the sensitive suspension.
3 Tubeless conversion / approx. 20 Euro
The tubeless conversion does not cost much and is quick, as most tyres are now tubeless-compatible. In addition, many rims are already supplied with an appropriate rim tape. The puncture protection increases and the wheel weight decreases. In this case, the tuning was particularly productive: with 250 grams per tube, we were able to save a whole 370 grams.
3. THAT DID THE TRICK
Driving report
Ride report From raccoon belly to toned six-pack: With 1.4 kilos less on the ribs, the before/after comparison of the Specialized Stumpjumper is the clearest. The Stumpi also gained the most in our points ranking. And that with a budget of just over 800 euros.
The first few metres off-road make it clear that the radical diet doesn't just have an impact on the scales. The All Mountain is almost unrecognisable when accelerating and is confident on the throttle. 1400 grams less on the wheels and tyres is a real statement. Despite the slightly narrower tyres we chose, you don't have to make any compromises off-road. With slightly higher air pressure (+ 0.2 bar), you can easily compensate for the theoretically lower puncture protection of the smaller tyre volume (2.35 instead of 2.6 inches). In addition, the Schwalbe tyre combination rolls at least as well and can even go one better in terms of grip. If you want to stick with the 2.6-inch tyre, you can still save weight with the Maxxis combination from page 38. To give the Stumpi even more sportiness, a slightly flatter handlebar would have been the icing on the cake.
CONCLUSION on the Specialized Stumpjumper Com pby Peter Nilges, BIKE Test Manager
When Specialized first made the storage space in the down tube accessible with a flap (SWAT door), the carbon frames initially put on a few pounds. In the current generation, however, the Stumpi frame is once again one of the lightest in its category and is therefore a perfect basis for a lightweight bike. In the overall package on offer, however, Specialized is gambling away the weight bonus with heavy wheels and 2.6 inch wide tyres. A successful feast for an effective tuning measure. With a reasonable investment of a good 800 euros, a whole 1.4 kilos less was possible, which ignited the turbo on the All Mountain. The fact that the entire weight was saved on the rotating mass means that the extensive diet has a particularly strong effect.
You can find this article in BIKE 10/2019. You can read the entire digital edition in the BIKE app (iTunes and Google Play) or the print edition in the DK shop reorder - while stocks last:
