Rocky Mountain Flatline Pro – First ride review

Downhill race-ready ride

Our rating 
3.5 out of 5 star rating 3.5
GBP £3,299.00 RRP | USD $3,999.00

Our review

A great downhill package with fantastic stability and masses of potential
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In 2009, Rocky Mountain ventured away from their freeride roots and developed this world-class downhill machine, with input from the top Maxxis-Rocky Mountain team. Six World Cup wins and numerous podiums later, it’s time to say hello to the Flatline Pro.


Ride & handling: Low-slung, stable and ready to race

The Flatline Pro felt well-balanced from the off, accelerating efficiently and more than happy to be pushed hard straight out of the gate. The Maxxis Minion DH 2.5in tyres didn’t love the British gloop so we changed them for a set of cut-down WetScreams to let the bike unleash its true potential.

Thanks to the Flatline’s stumpy head tube, low-rise Easton bar and integrated headset, the bar height can be kept nice and low, even with the fork dropped through the crown a little more to try and get the most of the head angle. Ours measured in at 64.5 degrees, which was pretty much spot-on.

The RockShox Boxxer Race fork isn’t overly supple in its initial stroke but does deliver a consistent feel and can take a real pounding when things get ugly. The external adjustments are simple yet effective and what’s more, the fork has potential for fettling.

The single-pivot, linkage-driven rear end is active enough to eat any small bumps, keeping the wheel planted in slower situations, and ramps up smoothly when the hits get bigger and faster. As the terrain gets wilder, the Pro provides enough feedback through the rear end to ensure you know what the wheel is up to, without getting rattled.

With the bulk of the weight between your feet, the Flatline’s cornering ability is great. Hammer the turns feet-up, and you’ll reap the benefits of the low centre of gravity with oodles of grip and confidence.

At high speeds the Flatline is stable and begs to go faster. With the Boxxer fork and RockShox Vivid shock working in sync, the bike covers ground rapidly with plenty of control, leaving you to pick and chose lines, and focus on keeping it pinned.

Frame & equipment: 7lb lighter than last year with tough, reliable kit spec

The Flatline Pro is sculpted from Rocky Mountain’s FORM 7005 aluminium tubing and has a 1.5in head tube with integrated headset and a super-stiff triangulated rear end with a 12mm through-axle.

Most of the weight sits deep in the frame with a sloping top tube for plenty of standover height and to keep the centre of gravity low. The RockShox Vivid 4.1 shock is driven by the LC2R linkage and boasts 213mm (8.4in) of well controlled and progressive travel.

Rocky Mountain have done a good job of shaving a whopping 3.2kg (7lb) from last year’s freeride Flatline, with the refined frame design and new build kit. Our complete bike (medium size) weighed in at 17.5kg (39.4lb).


The RaceFace Respond chainset and e*thirteen LS1 chainguide keep things running smoothly and reliably while the Boxxer Race fork gives a capable and predictable ride.

Product Specifications


Name Flatline Pro (10)
Brand Rocky Mountain

Available Sizes 16" 17" 18"
Brakes Avid Elixir 5 Hydraulic Disc 203mm
Cassette Sram PG-950-9 11-28T
Chain Sram PC951
Cranks Race Face Respond 170-175MM 36T / e13 LS1 Guide
Fork RockShox Boxxer Race
Frame Material RMB FORM 7005 Alu, World Cup Design
Handlebar Easton Vice Low Rise 711mm x Ø31.8mm
Head Angle 64.5
Headset Type FSA Orbit Z1.5 / 1 1/8
Rear Derailleur Sram X9
Rear Shock RockShox Vivid 4.1
Saddle SDG I Fly I Beam
Seatpost SDG I Beam Micro 30.9mm
Shifters Sram X7 Matchmaker Triggers 9spd
Stem Truvativ Holzfeller Direct Mount 50mm
Weight (kg) 17.5
Weight (lb) 39.4
Tyres Maxxis Minion DHF 2.5 FT/ DHR 2.5 RR A.V.
Front Wheel Alex FR32 rims, Wheeltech hubs
Rear Wheel Alex FR32 rims, Wheeltech hubs