There are a ton of different variants of the Nukeproof Reactor. You can pick either 27.5in or 29in wheels, carbon or aluminium frames and multiple price points in each category. Travel is matched to wheel size, so the 27.5in Reactor gets a 150mm fork and 140mm out back while our 29er test bike has 10mm less travel at both ends.

Also available as a frame only with Super Deluxe Ultimate RCT shock for £1,799.99

Nukeproof Reactor Pro 290 Alloy review

To reduce weight, Nukeproof uses triple-butted hydroformed aluminium tubing but with a carbon-fibre seatstay assembly. This carbon upgrade makes the rear suspension more sensitive by reducing unsprung mass, but we reckon it also improves the ride feel. Yes, heavier riders may find the Reactor a little too flexy, but for riders of average weight the stiffness and comfort from the chassis is right up there with the best full suspension mountain bikes.

Geometry is on the money too. It has a similar reach to the Specialized and Whyte, and while the head angle is steeper and the BB higher, you can shave 6mm off the latter and half a degree off the former, using the built-in (Trail/Rail) flip-chips. These inserts stay captured in the frame when you make the adjustment which is a nice touch.

Compression damping is easy to access and adjust

Suspension

Even though the 130mm rear suspension on the Pro 290 Alloy looks similar in layout to the Focus, it is a four-bar design with completely different kinematics. Once into the travel the Nukeproof has much more support, so you get none of that wallow under power. And even though we measured the rear travel at 127mm, it’s so effective it actually feels like it delivers more.

The RockShox Pike Select+ fork has a slightly different spring curve to the Lyric on the Whyte T160 RS V1 but it was a good fit for the rear suspension on the Nukeproof Reactor Pro 290 Alloy. We did bottom it a few times on our first downhill runs, so we added a Bottomless token and ran a little less sag. Even then the Pike doesn’t feel as stiff as the Fox 36, but we reckon the flex compliments the ride of the Pro 290 Alloy frame.

Flip-chips for Trail and Rail alter geometry

Components

Like all Nukeproofs, the cockpit on the Reactor employs the smaller 31.8mm interface, but again this adds to the overall ride feel. The Nukeproof handlebar has a good profile, and the 45mm stem length matches the reach on the size L Reactor perfectly.

The Brand-X Ascend post has 170mm of drop but the seat tube on the Reactor is a little taller than the other bikes in its class, so if you’re of medium height the saddle could be too high at full extension. Something worth considering when choosing which size to get.

Even when the SRAM Guide RE four-piston brakes had bedded in, the Nukeproof felt a little under-braked at the rear. It has a smaller 180mm rotor so if you’re a heavier rider we’d recommend upgrading to a 200mm rotor. Changing the Maxxis Dissector rear tyre could also help as it doesn’t quite have the braking traction of a Minion DHR II or High Roller II. Nukeproof runs the tougher EXO+ casings to ensure you’re not going to be smashing the rims, which is a good thing as the 28mm internal width is slightly narrower than those elsewhere to cut rotating weight.

Rear 180mm rotor sub optimal for the heavier rider

Performance

On paper, the Pro 290 Alloy is more upright than the other three bikes in the shop bought category. And when you’re charging downhill at full pelt, the ride can get a bit wild. But that’s hardly surprising because the bike has a generous 481mm reach, good tyres and decent cockpit that really egg you on.

Even having less travel isn’t a limiting factor. On the flipside it’s more agile and accurate on mellow singletrack, and when you’re darting in and out of the trees, popping off roots and rocks, it is the most fun here and the easiest to ride with confidence.

It climbs well too, and even if there’s a bit more suspension movement than on the Specialized, it’s still really efficient so you never feel like you’re working overly hard on the way up.

Nukeproof Reactor Pro 290 Alloy