Ryobi 40V 21-inch Brushless Smart Trek review

Powerful, long lasting and self-propelled, is the Ryobi 40V 21-inch Brushless Smart Trek the do it all mower for you?

Ryobi 40V 21-inch Brushless Smart Trek Review
(Image: © Ryobi)

Top Ten Reviews Verdict

The Ryobi 40V 21-inch Brushless Smart Trek offers a really viable alternative to gas with a maintenance free battery system that offers lots of range with dual batteries and lots of power. The 21-inch blade is great for edge-to-edge cutting while the quick adjusting deck height, handle and collection bag all make for easy use.


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    Five year limited warranty


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    Awkward full extension handle start required

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    No battery indicator on mower

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    Slow charging

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The Ryobi 40V 21-inch Brushless Smart Trek battery mower is a mean, green, grass-cutting machine. It sits in the higher end of the battery mower market in terms of price and features with the likes of self-propelled drive and a brushless motor leading the feature set.

Ryobi has managed to get lots of power out of its 40V battery for this mower, which houses two, allowing you to get even more range. On dual battery setup you can use this to cover a good half acre plot on a charge. 

The self-propulsion is called Smart Trek, by Ryobi, but it's essentially similar to what the competition offer with a push to go system. Unlike a lot of the competition this offers a true 21-inch cutting blade for plenty of width when cutting your lawn.

Charging could be faster and there were issues like a lack of battery display on the handlebars. But performance was impressive with lots of power and a high spin speed. Plus you get a reassuring five year limited warranty. 

Is this the best electric lawn mower for you? Read on to find out all you need to know.

Ryobi 40V 21-inch Brushless Smart Trek review: Design and build

  • 21-inch blade
  • Single point height adjustment
  • Steel deck

The Ryobi 40V 21-inch Brushless Smart Trek offers a reassuringly weighty steel deck without adding to the overall weight of the mower too much. It strikes a great balance between light maneuverability and solid weight, to power over bumps and lumps. While the deck is a pretty standard 21-inches, the blade is too. Most of the competition with a 21-inch deck actually feature a 20-inch blade. This slightly larger blade not only means more width and a wider cutting area but also a far better edge-to-edge cut making this great for fine detail cutting in to edges.

The brushless motor is also an appealing feature as this should have longer life and more power efficiency than a brushed equivalent. 

The single point height adjustment, becoming a popular feature on these types of mowers, is really welcome. It means you just need to pull the handle and lift or depress the deck to find the height you want easily. 

The LED headlights are a nice addition that allow you to cut when it's getting dark. Since these battery mowers are so quiet, it can be a genuinely useful feature when you want to cut at night when it's cool, without annoying your neighbors. 

The handle system is quickly adjustable and the bag is a simple clip in unit. Both of which are super easy to use. There is also a red kill switch key, should you want to do maintenance – although we find popping the battery out is just as reassuring. But it's nice to see Ryobi putting pro level features in this model.

Ryobi 40V 21-inch Brushless Smart Trek review: Features

  • Seven height adjustments
  • Self-propelled
  • Dual battery

The Ryobi 40V 21-inch Brushless Smart Trek's headline feature, according to Ryobi, is its Smart Trek self-propulsion system. This uses rear-wheel drive to help move the mower as you apply a little forward pressure on the handles. Rear-wheel drive, the company says, offers more traction when moving across the lawn.

This mower offers a three in one system meaning you can pick between bagging your grass, mulching it or side discharging it – although the side discharge accessory is sold separately. The bag itself is super easy to use thanks to the Easy-Life Single-Motion lock that is made for simple one handed use. 

The height of the deck can be moved through seven levels, with that one handed pull and adjust system. This ranges from as low to the ground as one and a half inches right up to as high as four inches. 

There is a dual battery bay which allows you to double the runtime of this mower, if you invest in a dual battery setup. When one runs out the other one kicks in, at which time you can pop the dead battery in a charger, allowing you even more juice when the second runs out and the first can be placed back in.

Ryobi 40V 21-inch Brushless Smart Trek review: Performance

  • Plenty of power
  • Decent runtime on two batteries
  • Easily adjustable

The Ryobi 40V 21-inch Brushless Smart Trek battery mower has got lots of power with a good 2,800 RPM making it one of the faster spinning mowers out there. This power allows you to glide over maintenance cuts of a lawn but, on longer grass it can slow and struggle a bit. It'll still cut through grass as deep as a month's worth of growth, making that four inch top height useful, but just not as easily as shorter grass the whole time.

In terms of battery life you can expect the included 6Ah battery to get you about a quarter of an acre of average cutting done before it gives out. So just over half an hour or so - the Stihl RMA 510 V offers 45 minutes and the Greenworks 21-inch 60V MO60L410 offers up to 90 minutes. But if you have that second battery you're good for an hour, or half an acre, easily. Also with the other battery charging you may be able to swap it back in after the second battery dies for even more range. That said charging is slow compared to some of the fast charging competition. 

The self-propulsion might take some getting used to as power is added as you lean into the handle, which can be difficult to apply evenly on slopes. As such it's not the smoothest to use right away but can be improved as you get better at judging how much you need to push and how much you need to just relax your arms.

To start it's a simple button push, but you do need the arms at full length. This is done easily with a single point of adjustment but is a hassle if you change it each time you use the mower. That said you can fold the handle down for vertical storage, so you're likely going to be messing with this anyway. 

The deck height adjustment couldn't be easier with that pull and move system that's really hard to fault, especially with those seven points of height – it feels just right. 

The grass collection bag is also very easy to use with a simple lift and release mechanism that makes it quick and easy to take off and attach again.

Should I buy the Ryobi 40V 21-inch Brushless Smart Trek?

If you want a super wide cutting area on a mower that offers plenty of power, easy adjustment features and LED headlights, this is ideal. It'll also give you enough runtime to cover a lot of space and the option to add a battery for even more range.

However, if you want a more intuitive drive system, longer battery range and a bit more power there are other options that are similarly priced.

If you're still set on a gas mower, then check out our round up of the best gas lawn mowers, while those with big lawns will want to take a look at our guide to the best riding lawn mowers.

Luke Edwards

Luke is a veteran tech journalist with decades of experience covering everything from TVs, power tools, science and health tech to VPNs, space, gaming and cars. You may recognize him from appearances on plenty of news channels or have read his words which have been published in most tech titles over the years. In his spare time (of which he has little as a father of two) Luke likes yoga, surfing, meditation, DIY and consuming all the books, comics and movies he can find.