Test Cube Phenix C:62 Rookie SLX: Carbon hardtail for up-and-coming racers
Jan Timmermann
· 17.12.2025
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It looks great, the Cube Phenix C:62 Rookie SLX - all the young test riders at the BIKE Youth Camp agree on this. Plus point for Cube, because as we all know, a children's bike also has to be appealing in order to be taken to heart as a toy and piece of sports equipment. With its detailed carbon frame, the Phenix Rookie is also the lightest hardtail that we put in front of the young testers. The test on the XC track will show whether this is enough to win over the cross-country-experienced talents.
Cube Phenix C:62 Rookie SLX in detail
- Price: 1699 Euro >> available here
- Area of application: Cross Country
- Suspension travel: 100 mm
- Wheel size: 27.5" (frame size XS)
- Recommended height: from 124 cm
- Recommended age: from 10 years
- Frame material: Carbon
- Max. Rider weight: 65 kg
- Weight: 10.8 kg
Equipment
- Suspension fork: SR Suntour Raidon 32 Air
- Gear system: Sram NX Eagle, 1 x 12
- Gear ratio: 32 / 11-50 t. (455 %)
- Brakes: Magura MT Thirty, 160 / 160 mm
- Seatpost: Cube Prolight aluminium, rigid
- Wheels: Newmen Performance 30 light/base
- Tyres: Schwalbe Rocket Ron Evo Addix Speed Super Race, 27.5" x 2.25"
How the children's mountain bike from Cube rides on the cross-country course
Even before the actual test starts, our young testers are sceptical. "That's stupid with the seat clamp!" exclaims Klara (156 cm, 12 years). In fact, the double clamp integrated into the carbon frame cannot be reached with a regular Allen key without removing the rear wheel. A quick adjustment of the extension with a multitool? No way!
The youth Phenix takes this questionable feature from the adult model. However, as there is less space available on children's bikes and impatient offspring are often pawing at the bike, the design element feels more like a bug to the test team.
The Cube Phenix C:62 Rookie SLX also shares its DNA with the pioneers from the adult sector in other frame details. For example, the rear brake is connected to the carbon frame using the flatmount standard and the bottom bracket using the pressfit standard.
The cables and lines all run through the headset into the inside of the frame. Great at first glance, but don't worry if there's something wrong with the children's bike. The poor serviceability is likely to cost some mums and dads a few nerves.
However, the uncompromising copying of the big mountain bike also has good sides. Cube uses branded parts that look good on the bike: Wheels, tyres, brakes - all not high-end, but absolutely fine and functional for the price.
Cube has saved on the suspension fork. Although the SR Suntour shines through the forest with a wonderful colour gradient, it cannot convince with sensitivity. Whilst it absorbs big hits, it lacks sensitivity on small bumps.
Even the narrow race tyres and the stiff carbon fibre frame are not very forgiving for kids. "Somehow I took more hits at the back than on my own hardtail," Klara complains and continues: "But it goes up really well. It definitely works better uphill than downhill."
The children's mountain bike from Cube is light and has a direct acceleration. This means that less energy is wasted than with the competition. Only very steep or very long ramps set limits for smaller riders. The 32-to-50 gearing would also be too tight for some adults.
The handling of the Cube Phenix Rookie was convincing in the test. Cube has opted for a size split and put our test bike in size XS on 27.5 inch wheels, while size S rolls on 29 inch wheels. Added to this are extra-short chainstays and a compact wheelbase. Well integrated, kids can manoeuvre the agile bike through corners without any effort. A compact reach and a short stem also help with agility.
As long as the root staccato doesn't get too strong, the hardtail is also safe on the piste thanks to its slack steering angle. Only on extra steep descents can the Cube with its rigid seatpost and high standover height feel unwieldy. The young test riders then felt more at ease on more docile bikes with more freedom of movement.
Geometry Cube Phenix C:62 Rookie SLX (frame size XS)
- Reach: 370 mm
- Stack: 607 mm
- Top tube length: 561 mm
- Chainstay length: 408 mm
- Wheelbase: 1066 mm
- Bottom bracket height: 326 mm
- BB-Drop: -41 mm
- Seat tube length: 355 mm
- Protrusion height: 780 mm
- Steering angle: 67,7°
- Seat angle: 73°
- Head tube length: 125 mm
- Stem length: 50 mm
- Handlebar width: 720 mm
Data from the BIKE test lab
At BIKE, we go to unprecedented lengths to test bikes. We are the only trade magazine in the world to operate its own test laboratory. The data obtained supports our impressions from the practical test. When it comes to geometry data, we don't just rely on the manufacturer's specifications, but also use the laser measuring device ourselves.
- Complete weight: 10.82 kg (size XS without pedals)
- Wheel weight: 4430 g (incl. tyres, tubes, cassette, brake discs)
- Impeller inertia: 3208 kg x cm² (the lower the value, the better the acceleration)
Conclusion
I really liked the Cube on the climbs. It has disadvantages on the downhill. I get really shaken up there. Also because the suspension fork is heavier than on my own bike. - Klara, BIKE young tester
The Cube Phenix C:62 Rookie SLX skilfully imitates its adult siblings and is a decidedly athletic children's hardtail that whets the appetite for junior racing. The frame details are stylish, but not necessarily practical for families. Small compromises have to be made when it comes to the equipment. However, the look and price are definitely hot! - Jan Timmermann, BIKE editor
Pro
- Clean look
- Discreet weight at an attractive price
- Sporty driving characteristics
- two frame sizes
Contra
- little ride comfort
- second-class suspension fork
Jan Timmermann
Editor
