eXmark Commercial 21 X-Series Lawn Mower Review

PTR Review
  • Overall Rating 9.4

For Pros who want to refuel less often and don't want to worry too much about the general durability of their investment, the eXmark Commercial 21 X-Series is one you definitely need to see for yourself.

Overall Score 9.4 (out of 10)

eXmark Commercial 21 X-Series Lawn Mower Just Keeps Going and Going…

We tested 24 mowers of both electric and gas variety to check the lay of the land in both the commercial and residential mower markets. You can read about all of that in our Best Gas Mower and Best Battery-Powered Mower comparison reviews. Today, we’re looking at one of the Pro-grade self-propelled gas models, the eXmark Commercial 21 X-Series Mower. Not only did it impress with its insane fuel capacity and runtime, but it also comes with some unique features that set it apart.

The Commercial 21 X-Series has several options. We’re testing the model with a self-propelled zone start and Honda’s GXV 160 engine. You can also get it with a Kawasaki KAI FJ180V engine in either the self-propelled zone or self-propelled BBC (blade brake clutch) designs.


  • Huge gas tank means tons of mowing without having to stop and refuel
  • Super-beefy build
  • Smooth speed adjustments
  • Excellent cutting power


  • Lower fuel efficiency than its competition
  • Height adjustment can be cumbersome if you change it frequently


We use a variety of tests to come to our conclusions and you’re welcome to take out word for it. However, we know many of you care about the substance of our testing. You can find those details in our gas mower shootout.

Cutting Power

We spent a significant portion of our testing by looking at each mower’s blade tip speed. The reason for this is pretty simple: the faster the blade tip speed, the easier it is for the mower to actually cut. As the grass gets taller and thicker, the engine’s ability to maintain that speed will determine how well it avoids getting bogged down and stalling out.

eXmark Commercial 21 X-Series Lawn Mower Review

We started out measuring the no-load speed of each mower’s blade and then measured the difference as we applied heavier loads. The eXmark Commercial 21 X-Series lawn mower started out cranking out 3129 RPM and 190.7 MPH tip speeds with its 20.5″ blade. That’s a solid number considering the class leader was at 194.8 MPH.

Under a light maintenance cut, there’s virtually no change in any of gas mower’s speeds. It’s simply just not enough load to have much effect on them.

Under heavy load similar to a couple of weeks worth of fast growth, the eXmark Commercial 21 X-Series lawn mower cranks out 3103 RPM and 189.1 MPH. This is only a drop of 1.6 MPH between the no-load speed and its speed under heavy load. Gas engines don’t struggle under a heavy load nearly as much as battery-powered lawn mower motors. Even so, the eXmark struggled the least among the commercial and residential models we tested.

Torture Test

We took a handful of our higher-performing mowers and threw them into a torture test. This amounted to mowing through five weeks worth of grass growth at a constant 2.5 MPH walking speed and set to a 2.5″ cut height.

eXmark Commercial 21 X-Series Lawn Mower Review

The eXmark Commercial 21 X-Series lawn mower made it 44.5′ before succumbing to the strangling nature of our overgrown bahiagrass. This was not a bad score, but it was bested by the Honda HRC216 (113′), the residential gas Cub Cadet SC900 (54.5′), and the battery-powered EGO Peak Power lawn mowers (60.5′).

Of course, this was a subjective test with too many variables to draw too many hard and fast conclusions. We didn’t factor these performances into our final score, but the results were still pretty interesting.

Overall, eXmark produces plenty of power as a commercial level mower. Even though it’s not at the top, we’re not disappointed in its cutting power at all.

Cutting Area

Running back to the trailer to grab the gas can in the middle of a job is inconvenient, so the more area a mower can handle on a tank of gas, the better.

eXmark Commercial 21 X-Series Lawn Mower Review

This is one of the areas where eXmark really put some thought into the user experience and simply dominates. Rather than throwing some piddly fuel tank on their commercial walk-behind, eXmark goes with nearly a gallon. It’s easily the biggest fuel tank we saw during the shootout.

Lo and behold, the eXmark Commercial 21 X-Series lawn mower covered the most ground of any other mower. It can get through 76,670 square feet on a tank (1.76 acres) and run for nearly 3.5 hours. Its closest competitor is more than 0.5-acre behind.

Fuel Efficiency

While you can mow a whole lot of grass on a tank with the eXmark, its actual fuel efficiency has room for improvement. Among both commercial and residential models, it has the lowest fuel efficiency we tested, despite its Honda GXV160 engine.

Teasing out our runtime data, eXmark gets roughly 1.88 acres cut on a gallon of gas. Even though their tanks are smaller, Honda leads the commercial group with an impressive 2.57 acres/gallon fuel efficiency. Residential lawn mowers are even better, reaching as high as 3.02 acres/gallon.

Feature Set

Self-Propelled Drive

The eXmark Commercial 21 X-Series mower features Infinite Speed Control. This is a multi-cone transmission that provides infinite speed control from 0-4.2 MPH. It has no gears to change and it’s super-easy to operate.

eXmark Commercial 21 X-Series Lawn Mower Review

Some of the mowers we tested had jerky self-propel drives, but eXmark’s is really smooth as you adjust through its speed range.

Deck Material

For the deck material, steel is the material of choice on gas mowers (some battery-powered lawn mower use plastic/poly). The exception to this rule is the eXmark Commercial 21 mower. It uses die-cast aluminum for its 5″-deep, 1/4″ thick deck.

eXmark Commercial 21 X-Series Lawn Mower Review

Height Adjustment and Range

The eXmark adopts yet another unique design for its height adjustment as well. Rather than the standard lever-based 4-point adjustment we see on other gas lawn mowers, the X-Series uses eXmark’s patented front height adjustment system.

To make adjustments pull up on the tab and pull the wheel and its accompanying axle out of the mower base. Then push the axle and wheel into the hole that corresponds best to the height you want and click it into place. The back of the mower adjusts via a lever that adjusts both wheels at once.

Pro Tip: Set the front wheels one level higher than the rear to improve your collection efficiency when you bag.

We have mixed feelings about the system. On the one hand, it’s kind of a pain to yank a wheel out of its socket, lift the mower, and replace the wheel. On the other hand, this is the sturdiest-feeling mower of the whole bunch, owing to the stability of this system in large part. Realistically, most people set one height and roll with it rather than making constant adjustments. For the extra rigidity, we’ll take it.

This mower has 8 height settings to choose from, ranging from 0.875″ to 4.250″. That’s plenty to cover nearly every species of grass you might come across.

Handle Positions

The eXmark Commercial 21 mower sticks with the standard 3 handle positions that lock into place by spring-loaded pin detents.

Discharge Options

Curiously, this eXmark lawn mower only allows for mulching and bagging. Side discharging your clippings is not an option here.

Additional Features

  • Easy on/off bag design
  • Guard rail on the front protects your mower’s vital parts


While we do look at price when considering value, it’s not the only thing we look at. We like to consider the entire design along with its performance to get an idea of its bang for your buck.

The eXmark Commercial 21 X-Series mower retails for $1,799, which is a bit more than its rival from Honda. It comes with a 1-year commercial warranty.

The Bottom Line

The eXmark Commercial 21 X-Series has the power and build quality we expect from a mower that carries the “commercial” designation. While you can find better cutting power and fuel efficiency, eXmark is hitting the mark with their design. It’s easy to use and runs forever on its massive gas tank.

For Pros who want to refuel less often and don’t want to worry too much about the general durability of their investment, the eXmark Commercial 21 X-Series is one you definitely need to see for yourself.

eXmark Commercial 21 X-Series Mower Specs

  • Model Number: ECX160CHN21000
  • Engine Model: Honda GXV160
  • Air Filter: Dual-element air filter
  • Drive System: Self-propelled, rear-wheel gear-driven
  • Transmission: Infinitely variable speed transmission
  • Fuel Capacity: 1 Gal
  • Speed: 0-4.2 mph
  • Speed Control: Finger-tip control
  • Weight: 123 lbs
  • Deck Style: Fixed, rear-discharge bagger and mulch plug standard
  • Cut Swath: 20.5″
  • Bag Capacity: 2.5 bushels
  • Warranty: 1-Year commercial
  • Price: $1,799

For more information about the eXmark Commercial 21 X-Series lawn mower, click here.

Related articles