At under 12kg in total, the top of the range 799 MSL is properly light for a bike with 150mm of travel. Looking at the spec, though, it’s no surprise – the Rocky Mountain grips sit on either end of Race Face Next Carbon bars and pedals screw into a choice premium enduro crankset. The light but unexpectedly bomber tough Race Face Next SL crank with its one-piece spider and chain securing narrow wide ring also uses a 30mm axle in the BB92 Press Fit bottom bracket shell.

The rims are Reynolds' Carbon All Mountain and the gearing SRAM XX1, meaning hardware on the Altitude is about as light as possible without obviously sacrificing strength. The same goes for the Smoothwall carbon frame, which uses hard internal forming mandrels rather than an inflatable bladder to create the most accurate high pressure shaped tube walls inside and out.

The level of construction control is evident in the use of subtle blister bumps for each internal cable entry port rather than simpler-to-make rubber grommet-plugged multi-control holes. There are multiple exit points for the cables and hoses, either underneath the top tube just ahead of the shock (used for a shock remote on this bike) or under the bottom bracket, where you’ll also find an extra bottle mount with fancy blue anodised bolts and chainguide mounts moulded into the frame.

While they’re not needed here, there are DMD front derailleur mounts built into the chainstay front end. A lack of cross bracing bridges means plenty of mud room even with the big 2.4in Ardent tires. We know riders who’ve ragged Rocky’s solid state ABC pivot bushings through long seasons of very varied weather without an issue, so we’re not worried about excess wear.

Combine stiff cranks, a light bike with light wheels and a semi-slick rear tire and the Altitude certainly isn’t slow at gaining its namesake. The Fox CTD shock comes with a handlebar remote control, which means you can firm it up or lock it out almost totally with the flick of the under-bar trigger or dump the low speed compression damping by releasing Descend mode. You get the same adjustment via the dials topping the Fox 34 fork too, so prepping it for long stints of climbing or just adapting ride feel for changing terrain is no problem.

The rotatable Ride-9 chip within a chip feature that holds the front of the shock also lets you change geometry and/or shock rate. That means you can have a really steep seat angle and steeper head angle if you prefer clawing up similarly steep climbs or something much slacker and lower for carving the corners. RockShox’ seemingly omnipresent Reverb Stealth dropper post means seat height is never an issue and powering up the fire road of Bootleg Canyon things seemed all set for an impressive first ride of the demo.

Unfortunately that’s not quite how it panned out because of a shock issue that caused severe high speed spiking on our sample. Luckily we were riding a Rocky Mountain Instinct 990 29er with an almost identical suspension setup at the same time so we know the suspension – while noticeably linear and fairly pressure sensitive – is basically sound.

The suitably slack and low geometry combines with the excellent Maxxis DHF triple compound front tire and short stem, wide bar Race Face cockpit for a front end you can really put weight into. The Ardent rear tire acts as a natural drifting ‘fuse’ too, stepping out seemingly automatically just as the front end starts to slide and turning potentially dangerous understeer into big grin, back end out oversteer.

The light weight and easily compressed shock feel make the Altitude very easy to hop and pop around on the trail too, so you can generally keep it clear of the big hits that might make its lack of planted rigidity an issue.

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