Growler 50

The 2021 and newer Rocky Mountain Growler is an aggressive aluminum trail hardtail designed for riders who prioritize descending capability over cross-country efficiency. Built around 29-inch wheels and high-volume 2.6-inch tires, it applies the long, slack design philosophy typically reserved for long-travel full-suspension bikes to a rigid frame.

Rather than serving as a lightweight climbing specialist, the Growler is positioned as a burly, durable platform meant to be pushed hard on steep, rough terrain. It suits budget-conscious riders looking for a highly capable primary mountain bike, or experienced riders wanting a modern, low-maintenance hardtail that does not force them to drastically alter their line choices on challenging descents. The frame utilizes proven, easily serviceable standards like a threaded bottom bracket and external headset cups, underscoring its utilitarian intent.

$1,999Model Year 2025

Year

Build

Size

Stack	643mm
Reach	450mm
Top tube	620mm
Headtube length	110mm
Standover height	802mm
Seat tube length	420mm

Fit and geometry

The Growler’s handling is defined by a starkly progressive geometry chart, highlighted by a 64-degree static head tube angle and a long wheelbase that stretches past 1,230mm on the size large. Because a hardtail only sags at the front fork, this exceptionally slack static head angle steepens slightly under rider weight, settling into a balanced but still aggressive posture on the trail.

To maintain climbing traction and pedaling efficiency, Rocky Mountain pairs the slack front end with a steep 75-degree seat tube angle. This places the rider squarely over the bottom bracket, preventing the front wheel from wandering on steep ascents despite the long reach. The cockpit setup reinforces the bike’s downhill bias, utilizing wide 780mm handlebars and short 40mm stems across all sizes to maintain responsive steering leverage. Combined with short 435mm chainstays, the rider is positioned centrally between the wheels, encouraging a forward, attacking stance that maximizes front-wheel grip through fast corners.

Full specs

Frameset

Frame

Rocky Mountain 6061 Alloy | Threaded BB | Boost 148mm | Tapered Zerostack Headtube | Dropper Post Compatible

Fork

Marzocchi Z2 Float EVOL Rail 150mm | 44mm Offset

Groupset

Shift levers

Shimano Deore 12spd

Rear derailleur

Shimano XT

Cassette

Shimano Deore 10-51T 12spd

Chain

Shimano M6100

Crankset

Shimano Deore | 30T | 24mm Spindle | Crankarm Length: SM - MD = 170 | LG - XL = 175mm

Bottom bracket

Shimano SM-BB52

Front brake

Shimano MT4120 4 Piston | Resin Pads

Rear brake

Shimano MT4120 4 Piston | Resin Pads

Front rotor

null

Rear rotor

null

Wheelset

Front wheel

WTB ST i30 TOUGH TCS 2.0 | 32H; Shimano TC500 | 15mm Boost; 2.0 Stainless

Rear wheel

WTB ST i30 TOUGH TCS 2.0 | 32H; Shimano TC500 Boost 148mm; 2.0 Stainless

Front tire

Maxxis Minion DHF 2.6 EXO Tubeless Ready

Rear tire

Maxxis Minion DHR II 2.6 EXO Tubeless Ready

Cockpit

Stem

Rocky Mountain 35 AM | 0° Rise | All Sizes = 40mm

Handlebars

Saddle

Rocky Mountain 148 Cromo

Seatpost

X Fusion Manic Composite 30.9mm | XS - SM = 125mm | MD = 150mm | LG - XL = 170mm

Grips

Rocky Mountain Lock On Ergo

Builds

The Growler lineup is structured to offer accessible entry points while maintaining the same 6061 alloy frame across all models. The frame features internal cable routing, Boost 148mm rear spacing, and dropper post compatibility.

Lower-tier builds like the 20 and 40 utilize Suntour forks and basic two-piston Shimano brakes, keeping costs down while delivering wide-range gearing suitable for steep climbs. The flagship Growler 50 steps up to a 140mm or 150mm fork—such as a Marzocchi Z2 or RockShox 35 Gold, depending on the model year—and upgrades to a 12-speed Shimano Deore/XT or mixed SRAM drivetrain. The 50 also introduces four-piston front brakes for better heat management on long descents.

Across all builds, the specification relies heavily on 2.6-inch tires from Maxxis or WTB mounted to 30mm internal width rims. These high-volume tires are critical to the bike's ride quality, allowing riders to run lower pressures for necessary damping. While the stock components are generally praised for their durability, multiple reviewers suggest that aggressive riders will quickly benefit from upgrading the stock resin brake pads and rotors to metallic versions for stronger initial bite.

$1,999

2025Selected

Reviews

Reviewers consistently highlight the Growler’s exceptional stability at speed, noting that its progressive shape allows it to tackle terrain normally reserved for longer-travel bikes. Testing the Growler 40, Mike Levy noted it was the only hardtail in his test group that he "rode like a full-suspension bike" (PinkBike), taking the same lines and carrying similar speed. The stiff aluminum frame transfers power directly, but testers emphasize that the high-volume tires are essential for muting trail chatter and preventing fatigue on long descents.

While the bike excels when pointed downhill, its length and slack front end introduce distinct handling tradeoffs at lower speeds. Reviewers found the bike requires deliberate input on flat terrain and can feel "sluggish in tight spaces" (Bigbluetire) or awkward on slow, technical climbs.

Despite the demanding low-speed handling, the consensus points to a highly capable descender that rewards an active riding style. The geometry provides a wide margin for error on steep trails, making it "possible to charge through chunk more recklessly" (Bike Magazine) than on traditional hardtails. Ultimately, testers view the Growler as a specialized tool that trades low-speed agility for unflappable composure when the trail gets rough and fast.