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Today’s DealsNucleus 26
A 24″ / 26″ aluminum frame hardtail crosscountry bike with upper mid-range components.
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Manufacturer Price
£629($844)| Weight | 28.0 lbs |
|---|---|
| Frame | Aluminum |
| Suspension | Hardtail, 100mm |
| Fork | Suntour XCR Air |
| Wheels | 24″ / 26″ Aluminum |
| Drivetrain | 1 × 8 |
| Groupset | Box Four |
| Brakes | Hydraulic Disc |
4'1" – 4'7"
4'4" – 5'1"
None yet.
Do you have this bike? Help other riders make a decision about which size will work for them by sharing your own size and fit notes.

Aug 2023 · Alan Muldoon
Head over to the Vitus website and you could be forgiven for thinking that you’re seeing double. You’re not, it’s simply that Vitus offers the Nucleus VR with either 27.5in wheels or 29in wheels. Both options are the exact same price and both come with very similar wheel size appropriate build kits, that include different fork travel, different tyre sizes and different gearing. Best hardtail mountain bikes: classic trail-shredding machines Regardless of your preferred wheel size both options also use bespoke alloy frame designs, where Vitus has sensibly used the wheel size split to offer subtly different size ranges. The 27.5in wheel bikes run from S to XL, the 29ers from M to XL. The idea being shorter riders will benefit most for the smaller wheels, as they need more bum/tyre clearance. To keep the test fresh we opted for the Nucleus 29 VR, as we know from experience that bigger wheels roll over bumps better, especially when you have zero rear suspension, so they keep the rider fresher too. The lightweight alloy 29er frame has all the features you’d expect on a modern trail hardtail. A tapered headtube, internal routing for a dropper and ISCG tabs on the bottom bracket shell for fitting a chain device. And even though the seat tube has a slight kink in it, to help tuck the bigger 29in rear wheel in nice and tight to keep the chainstays short, there’s still plenty of seat post insertion, so getting the saddle well out of the way for shredding is easy. Suspension One of the big differences between the 29in Nucleus VR and the 27.5in bike is that it has 20mm less fork travel, so 100mm vs 120mm. Both bikes get the Suntour XCR 32 LO-R which is air-sprung and easily adapted to different rider weights. The fork also has externally adjustable rebound damping, but that’s not enough to put it level pegged with the fork on the Carrera, as this fork is really sticky. Maybe the bushings were too tight, but even with all of the dials wound wide open the fork was slow to react to impacts and very harsh. And while you could take one look at the 9mm quick release dropouts and assume the fork wouldn’t be stiff enough, Vitus is the only brand in this category to use a tapered steerer tube, so fork stiffness isn’t a problem. Components With a Nukeproof riser bar and 50mm Vitus stem the cockpit on the Nucleus is totally sorted – the lock-on grips a real bonus in wet conditions. The Maxxis Ardent tyres also offer a good compromise between rolling speed and traction, and will definitely dig in better in loose conditions than the lower profile Ikon tyres on the Polygon. We were impressed by the Clarks brakes too, as they were more powerful than the Tektros and have a light lever action just like the Shimanos. In fact, the only question mark over the build kit is the 8-speed Box drivetrain. Yes, …Continue reading »
Choice of wheel sizes. Sorted cockpit components. Maxxis Ardent tyres are a sound choice. Powerful Clarks brakes. Low weight
Sticky fork. Only eight gears. Tall seat tube

May 2021 · Alex Evans
Despite some decent parts, the Nucleus has a disappointingly stiff and XC-biased ride
Shimano Deore-based drivetrain works well
Good grip from tyres in most conditions
Geometry compromises all aspects of performance
Fork suffers from stiction
Stiff-feeling ride
| Frame | Nucleus Aluminium - 26" Wheel, BSA threaded BB, IS disc brake mounts, 135mm x 9mm QR Axle BB Standard: BSA, 68mm, Threaded Color: Bright Blue or Copper |
|---|---|
| Fork | Suntour XCR-DS-LO Air Forks, 100mm travel, IS Mount, 100mm x 9mm QR Axle, Lock-Out, 1 1/8" Steerer Travel: 100mm Spring Type: Air |
| Shock | N/A, N/A |
| Bottom Bracket | Samox BSA 24mm, BSA Threaded, 68mm Wide, English Thread |
| Headset | Neco No:11G, Semi-Cartridge, 1.5mm Top Cover, Height 9.8mm |
| Stem | Vitus 6061 Aluminium, 40mm Length, +/- 3° |
| Handlebar | Vitus 6061 Aluminium, 15mm Rise, 9° Back Sweep, 700mm Wide |
| Saddle | Vitus, Kids Specific, Steel Rail |
| Seatpost | Vitus 6061 Aluminium, 27.2mm x 250mm, 20mm Offset Type: Rigid |
| Grips | Vitus, 110mm, Closed End |
| Rear Derailleur | Box Four 8, 8 Speed w/ Clutch |
|---|---|
| Front Derailleur | N/A, N/A |
| Crank | Prowheel, 165mm Crank Arm, 32T, Double Chain Guard, Reduced Q Factor |
| Shifters | Box Four 8, 8 Speed |
| Cassette | Sunrace CSM680, 11-40T, 8 Speed |
| Chain | Box Four 8, 8 Speed |
| Brakes | Clarks Clout Disc Brake, Hydraulic, Reach Adjust Type: Hydraulic Disc |
| Rims | Front: WTB ST i25 TCS 2.0, 26", 32 Hole, Disc Specific, Rear: WTB ST i25 TCS 2.0, 26", 32 Hole, Disc Specific |
|---|---|
| Front Hub | Vitus KT, K08F, 32 Hole, 6 Bolt, 100mm x 9mm QR |
| Rear Hub | Vitus KT, K08R, 32 Hole, 6 bolt, 135mm x 9mm QR, 8/9/10 Speed HG Freehub |
| Tires | Front: Maxxis Ikon, 26” x 2.2”, Rear: Maxxis Ikon, 26” x 2.2” |
| Disc Rotors | Clarks Clout, Front: 160mm, Rear: 160mm |
First added September 23
Last updated July 13
Not listed for 685 days