The One Plus item in question today is the OLM1840H lawn mower – a battery powered cutter with a 40cm deck. The question is, are the Ryobi cordless lawn mowers any good?

My first thought upon seeing it was “Transformers”, but it certainly fits into the Ryobi brand image. We’re jumping ahead a little with the above pic – let’s start at the start and look at the assembly required out of the box. There’s two clamps for the top part of the handle;

Make sure you turn them around so that they close properly or you won’t get far attaching the handle:

Attaching the top to the bottom piece takes under a minute for both sides:

You’ll also have to tighten the lower clamps (here pictured loose):

There’s a key;

Not much to it:

The key plugs in next to the batteries under the clear cover at the front:

At the rear, lift the flap:

…and you will see the mulch plug in place:

If you want to use the catcher, push the handle inward and lift it out:

Hook the catcher up:

Plug your batteries in:

…and you’re back to the first photo of the article, ready to go. From the other sides:


One from underneath for good measure:


The height adjustment has only five settings, but it does seem to have been styled with a sportscar gear shift in mind;

On the side there’s a sticker with a little bit of info about it:

There’s a broad handle on the top of the unit:

The handle is quite handy (pun intended), particularly for those who make use of the fact that the mower is light enough that you could feasibly hang it on a wall to keep it out of the way.
The on button is on the right hand side of the handle:

Next to it are the instructions for powering it on:

Basically, press the “on” button once then hold in any one of the four triggers:


The mower will power off as soon as you stop holding down at least one of the triggers, though it’s quite happy to stay on if you swap hands/positions so long as at least one is held in at any given time. The triggers are quite light, and it’s not a big ask to hold one in while you’re pushing the mower around.
And there you have it. Some essential specs for the mower:
- Takes 18V One Plus batteries (two of) – with LED indicator
- 17.7kg
- 400mm cutting deck
- 20mm-70mm cutting height, 5 increments total
- 50L hard top, mesh catcher
- Mulch or catch
- Folding handle
One of the biggest things that struck me was the weight of the unit – it’s literally half of what our previous 4-stroke mower was, and you can really notice the difference when you’re pushing it around. The next big thing was the ease of starting when compared to our old petrol unit; tapping a button is a world apart from the prime-pull-pray routine of the elderly petrol machine, and certainly easier on the back.
Given that we only had a single 4.0ah battery and a number of smaller 1.5ah batteries, we thought we’d see how far we could get with the little ones in the mix. As it turns out, each of the 1.5ah batteries was good for about 40-50 square meters of wet grass, varying in length up to a foot high. I’m no expert on grasses, but the type we have is fairly soft and I imagine on the easier end of types to cut.

Mulching and catching both worked well, except on one occasion where the wet grass plugged the hole to the catcher, resulting in the mower going back to mulching the grass. I’m happy to write that one up as user error, as it hasn’t happened on any of the subsequent uses with dry grass. The 5 height settings are enough for our uses, and the range is certainly sufficient – I certainly don’t have any need to go for the lowest setting! The mesh catcher seems to work well enough, though I do wish it had a handle on the rear as well as the top to make shaking it out easier.
Last but not least, the noise levels! I can hear my kids talking to me through the gauze windows while I mow outside; it’s far from silent, but it’s much quieter than the petrol mower it is replacing. Think of a large industrial fan whizzing along at ground level and you might have the right idea.
We’ll report back when we acquire a second bigger battery with some runtimes. We have around 150 square meters of grass to cut, and anticipate getting the lot done with a pair of 4.0ah batteries.
In conclusion, the pros are:;
- Lightweight
- No fuel/oil to worry about
- Uses batteries you may already own for power tools
- Quiet (relatively)
Cons:
- Battery powered… runs flat, wait for a charge
- Not cheap
- Few height settings
- Likely unsuited to large lawns, unless you own many batteries or can wait for the charge times
It’s currently $379 without batteries at Bunnings, and it comes with a two year warranty. We’re quite happy with the purchase as it fits our needs well, and would absolutely buy another one.