Rocky Mountain Growler 40 Review
Cons: Poor tire specification, upright rider position, less stable at speed
Manufacturer: Rocky Mountain
Compare to Similar Products
Our Analysis and Test Results
Should I Buy This Bike?
The Growler 40 is a relatively capable hardtail mountain bike that has a preference for moderate speeds and terrain. This entry-level bike is comfortable with a relatively upright riding position and girthy 2.8" wide tires. It excels on smoother trails and more rolling terrain, though it is capable of riding more aggressive terrain with a controlled and calculated approach. Testers enjoyed riding the Growler on the right terrain and within its noticeable speed limit, as it did feel somewhat less stable at speed than some of the competition. That said, when not pushing the limits of speed or aggressiveness, the Growler was a comfortable and faithful companion for long hours in the saddle. We found it to be most appropriate for less aggressive riders and terrain and feel that it would probably work quite well for anyone dabbling in the adventurous world of bike packing.
The Growler 40's frame is constructed from 6061 aluminum tubing. The frame has a tapered head tube, external cable routing (internal for the dropper post), and boost spacing. There are two bottle cage mounts within the front triangle. Our large framed test model measured with a 628mm effective top tube length and a 438mm reach. The head tube angle was 67-degrees and the effective seat tube angle was 73-degrees. The bottom bracket height was 311mm with a 1170mm wheelbase and 444mm long chainstays. It weighed in a 30 lbs and 10 oz with tubes but without pedals.
- Available in aluminum frame only
- 27.5"+ wheels only
- Designed around a 130mm travel fork
- Clearance for up to 3.0" tires
- Available in 4 sizes, S-XL
- Offered in three builds ranging in price from $899 up to $1,849
The Rocky Mountain Growler is a fun bike on most trails but it has a speed limit. There's nothing particularly exciting about it, but it rides predictably and is capable on the vast majority of terrain. It performs best on smoother trails and more moderate grades and can even get into some steeper and chunkier terrain as long as you do so with control. Somewhat modern geometry helps it handle a majority of trails while the component specification reminded our testers that there are limits to what a $1300 hardtail is designed to handle. If you're not especially concerned with getting rad or tackling rowdy terrain, the Growler is a solid bike for getting out on the trails and could certainly work as an entry-level bike packing rig. More aggressive tires would do wonders for the Growler's performance in steeper terrain and loose conditions and bring the fun factor way up.
The Growler felt comfortable and reasonably composed on most descents. Relatively modern trail geometry and a reliable part spec helped testers adapt quickly to the bike. A couple of geometry and part choices kept this bike from keeping up with the Fuse 27.5, Giant Stance, or Marin Hawk Hill on the descents. Still, being comfortable and predictable isn't necessarily a bad thing, though this isn't the best choice for those looking to descend super aggressively.
The Growler has some, but not all, of the touches of modern trail bike geometry that help the bike feel stable and confident on the descents. The low bottom bracket helps the bike hug the ground in corners. The 67-degree head angle makes the steering pretty confident and predictable when traveling at higher speeds or down steeper trails. The wheelbase is still fairly short, giving it a lively and quick sensation, but it sacrifices some stability and composure when riding at higher speeds. The only trend Rocky Mountain didn't include was a longer reach. The bike's cockpit feels compact when descending, especially when compared to the stretched out Marin Hawk Hill.
A couple of components on the build package kept the bike testers from pushing the limits of this bike. The Suntour Raidon 34 fork felt good on big impacts but didn't seem to move at all on smaller bumps. The Best in Class Giant Stance had the same exact fork with far better small bump sensitivity. The lack of small bump compliance made both technical uphills and downhills a fatiguing endeavor as the feedback was quite noticeable. The Growler 40 sports WTB Ranger tires 27.5 x 2.8 tires, the same tires found on the Salsa Timberjack Deore. These tires roll fast making the bike feel quick and sporty for a plus-sized bike. The downside is the low profile knobs, and rounded side to side profile provides almost no traction in loose conditions or when trying to brake quickly. If you pull the brakes hard the tires quickly break loose and begin skidding. These tires perform best on smooth hard-packed trail surfaces, though they don't inspire tons of confidence in loose conditions.
Once again, nothing about the Rocky Mountain Growler stood out as particularly good or bad when climbing. The gear range was easy enough to muscle up the steepest trails despite not being the cleanest shifting. The 2.8" tires provided plenty of traction to climb up most technical or loose climbs. The cockpit was comfortable but a little more upright then you'd want if you plan on chasing those uphill KOM's on Strava.
When looking at the geometry charts for the Rocky Mountain Growler a lot of things made sense based on the ride feel. The reach and top tube length are the shortest of all the bikes in our test. Top tube length is essentially how far the seat post sits from the top of the head tube at the front of the bike. This distance dictates how stretched out a rider will feel when seated on the bike. The other number that stood out was how tall the stack (front end) is, 628mm on a size Large. As soon as our testers started riding this bike, the first comment was how upright this bike feels. When you are sitting and pedaling, the handlebars are closer to the rider and higher off the ground than any other test bike in this group. The upside of this is that older riders or people with back or shoulder injuries may be more comfortable riding in this upright position. The downside is that once climbs become steeper, the rider's weight is more upright and the front wheel tends to lift off the ground more easily, a characteristic our testers noted throughout their test rides. This wheel lift wasn't nearly as bad as experienced on the Salsa Timberjack with its ultra-short chainstays.
Aside from the Giant Stance all these test bikes featured a Shimano Deore 10-speed drivetrain. The only difference is Rocky Mountain decided to install an 11-46t cassette instead of the standard 11-42t. The easier gearing is helpful for spinning out the legs or being able to continue grinding up a steep, sustained climb. Once again, the shifting isn't quite as crisp with the larger change between gears, but the easier gear is always a welcome friend when things turn steep. The plus-sized tires and their large contact patch also helped with decent rear wheel traction.
All the bikes in this budget class provide a great value to consumers. At $1,359 the Rocky Mountain Growler 40 is the mid-priced option from our test. When shopping this price range, a couple of details can make a big difference in performance. Rocky Mountain checks a few key boxes by offering a dropper post, as well as tubeless compatible tires and rims at under $1,400.Fork--
The Growler 40 is equipped with a Suntour Raidon 34 LOR Air fork with 130mm of travel. This particular fork worked well at soaking up more significant impacts on the trail. When it came to small bumps or sections or high-frequency chatter, testers reported it feeling as if the fork didn't seem to do much. It felt almost stuck in place until a more substantial impact broke it free to absorb the impact. The Giant Stance 2 came with the same fork without the same problems. Perhaps it is inconsistency in manufacturing, though we can't be sure what caused the difference.
Wheels and Tires--
The wheels on the Rocky Mountain Growler feature 35mm wide Alex rims and Shimano hubs. The wider rims pair well with plus-sized tires to increase air volume and run them at lower pressure for increased damping and traction. The WTB Ranger 27.5 x 2.8" tires are fine in the appropriate conditions. They are fast-rolling, but once the dirt gets dry or loose the tires have a hard time finding any traction, especially when cornering. If you live somewhere with firm compacted dirt and mellower trails, these tires roll fast and provide adequate traction. We would have preferred something a little more aggressive.
The Growler 40 comes spec'd with a Shimano Deore 10-speed drivetrain. This is a pretty standard drivetrain for bikes in this price range. Every bike in this budget test came with this drivetrain except for the Best in Class Giant Stance. We had no issues during the testing period with the drivetrain, though it feels somewhat cheap when compared to the gear range and shifting performance offered by the SRAM 12-speed SX drivetrain on the Giant Stance.
Handlebars, Seat and Seatpost
The Rocky Mountain has the nicest dropper post of all the test bikes in this budget group. The X-Fusion dropper post has been on many of our test bikes in the past with infinite saddle positions and no reported problems within our bikes. A WTB Volt saddle is a reasonably comfortable saddle with a medium amount of padding. The Volt has a crowd-pleasing shape and width and is a safe bet for a stock saddle. The Rocky Mountain handlebars had a natural feel. The 760mm width is plenty wide for most riders, and most people coming off an older bike will still feel like these bars are wide enough.
The upgrade that would make the most significant improvement in bike handling and capability would be new tires. A tire with larger knobs would drastically increase the braking power and cornering ability of this Rocky Mountain. Once you need to replace them, a more aggressive tire will drastically improve the handling of this bike.
The next obvious upgrade would be the fork. It is hard to recommend upgrading a fork on a lower end bike. Many suspension companies don't offer lower to mid-level forks for aftermarket purchase. A high-end fork will run you anywhere from $600-1200. It typically makes more sense to spend a little more money on a higher-end build than to make this type of upgrade.
The $1,359 Rocky Mountain Growler 40 is the middle of three build options offered.
At $899 the Growler 20 drops customers down to a Shimano Altus 9 speed drivetrain and a rigid seat post instead of the X-Fusion dropper post. It comes with lower-level Shimano MT-200 brakes as well as the lower-level SR Suntour XCR 34 fork that comes on the Salsa Timberjack we tested.
At the higher end of the Rocky Mountain build options is the Growler 50 priced at $1,849. For the $500 increase in price, customers are treated to the new RockShox Revelation RC fork with 140mm of travel. This Revelation is one of the best performing mid-range forks on the market. It also comes with Shimano's 11-speed SLX drivetrain for improved shifting performance. Otherwise, the build kit remains almost exactly the same as the Growler 40 we tested.
All of the budget bikes in this test provide great value to the consumer, and the Growler 40 is no exception. This hardtail comes with a dropper post and can be set up with tubeless tires to improve downhill handling and traction. The capable middle of the road performance won't knock anyone's socks off, but will get you out on the trail with predictable and reliable performance. This bike checks a lot of boxes for a reasonable $1,359.
The Rocky Mountain Growler 40 doesn't stand out as the best performing trail bike in our budget test. It can still easily handle most trails confidently as long as the dirt isn't too loose or the trail too steep. For less aggressive riders who like an upright body position, this could be a good option for getting out on the trails without breaking the bank. The Growler 40 could also be a solid entry-level option for the rider who is contemplating getting into bikepacking.
— Jeremy Benson, Kyle Smaine