A brilliant strimmer, with a powerful engine – but the distinctive shaft shape makes it hard to use if you aren't tall.
- Ergonomically designed for comfort
- Powerful, easy-start engine
- Excellent on tough grass
- Awkward for a short user to handle
- Slightly fiddly strimmer cord replacement
- Review Price: £259
- Innovative 4-stroke GX25T engine
- Delivers up to 7000rpm for cutting
- Fuel tank capacity 0.58 litres
- Weight without petrol 5.4kg
- Tap and go double line
- Five-year domestic use warranty
What is the Honda UMS 425 LE Grass Trimmer?
The Honda UMS 425 LE is the lightest machine in the Honda Brushcutter range. It’s powered by Honda’s four-stroke GX25T micro engine, which drives a six-splined drive shaft (as opposed to a traditional groove key design) for added strength. This engine uses a special type of non-contact bearing – the same as those used by NASA – that’s resistant to dust and is extremely quiet. It also has a heavy-duty shock-resistant transmission unit.
The Honda UMS 425 LE has a curved-tube shaft to get to hard-to-reach areas, and is only for grass cutting. It’s designed to complete the job started by a lawnmower, cutting grass along walls, around trees and on narrow or uneven surfaces where a lawnmower cannot reach. The clutch is low-vibration, and there’s a semi-automatic bump and feed line system.
Related: Robomow RS635 Pro SX review
Honda UMS 425 LE Grass Trimmer – Design and features
The Honda UMS 425 LE arrived fully assembled, apart from the second handle and the cutter head guard, which had to be attached using an Allen key included in the box.
The machine isn’t height-adjustable, and you can’t extend it. You can move the second handle up and down the shaft to make the machine more comfortable for users of different heights, but it isn’t a quick adjust. You have to use the supplied Allen key to loosen it, as opposed to flicking a lever, which you can do on electric strimmers.
However, this doesn’t really matter because, in most cases, the second handle will be fixed in place by the main user and simply stay in that position. To edge, you simply turn the machine upside down.
To start the Honda UMS 425 LE from cold, push the red start/stop button to ‘start’, then put the choke in the high position. There’s a bubble primer below the carburettor, and you press that a few times to bring petrol out of the tank into the carburettor.
Next, you pull the recoil starter cord vigorously until the engine starts. After the engine has ticked over for about ten seconds, return the choke to the low position; the engine will then settle into a steady, quiet tick-over, and is ready to go.
Press the yellow safety catch on top of the shaft to “On”, then press the yellow throttle trigger under the shaft.
There’s a minimal guard on the cutting head, which means you can swing left and right with ease.
To replace the strimmer cord, press two tabs to release the cutting head, take out the spool, remove the remains of previous cord, and wind on new double cord. To do this, you take a length of strimmer cord, fold it in half, hook it into a recess in the centre of the spool, and wind the two lines around their separate places in the spool. Then you put the spool back. The eyelets have a slot, so you don’t have to feed the ends through anything; you simply click the cord in place.
A spark-plug wrench is supplied, so you can easily change the spark plug. To do this, take the red engine cover off using the Allen key. The spark plug sits beneath; unscrew it with the special wrench and replace it with a new one, screwing this finger-tight into its seat. Then you put the cover back.
Note of caution: most strimmers are two-stroke, so don’t have a separate oil sump. This four-stroke does, so you have to remember to check the oil level each time you use it. The Honda UMS 425 LE comes with safety glasses.
Related: Best grass trimmer
Honda UMS 425E Grass Trimmer – Handling and performance
When I held it (and I am 6ft 5in), the Honda UMS 425 LE was at the perfect height to get the right angle of cut for strimming. It was parallel with the ground: that way, the grass wasn’t cut unevenly, causing a scalloped effect. My girlfriend was surprised by how light and easy the Honda UMS 425 LE was to hold, but at only 5ft 4in tall, she found she had to lift up the engine head slightly to get the right cutting angle.
Even when wearing the very comfortable, fully adjustable padded harness that comes as an optional extra, she found lifting the engine head as she worked tiring after a while. So this machine is a better choice for taller users.
I found the Honda UMS 425 LE really enjoyable to work with. Although it’s heavier than comparable cordless machines, it displayed minimal vibration – which is a plus if you suffer from conditions such as arthritis or vibration white finger (an occupational disease of professionals).
The strimmer handled short and long grass with ease. Nettles weren’t a problem for it, and neither were young brambles and docks. Fat hen (Chenopodius album), a common fibrous weed, often proves a challenge for strimmers, but the Honda UMS 425 LE chewed through it easily. It took less than five seconds to cut a square metre of three-inch long lawn grass.
The narrow guard on the Honda UMS 425 LE meant that I could easily cut around small trees and bushes by swinging left and right. However, the length of the machine meant that it wasn’t ideal in tight, confined spaces.
Since you can’t adjust the Honda UMS 425 LE, you can only trim the top of a bank by holding the machine up at the right angle. This works, but isn’t comfortable for long periods.
When I tried edging by turning the machine upside down, the curved tube shaft kept trying to swing itself upright again, so the action was stressful. You need control for edging, which you’ll never really have using such a big machine upside down. For that reason, a smaller strimmer with an angled head is better if you’re after a super-professional edging job.
Related: Best cordless lawn mower
Why buy the Honda UMS 425 LE Grass Trimmer?
The Honda UMS 425 LE is a lovely bit of kit, good for a professional or someone with a paddock or large garden and plenty of grass and weeds to cut. It’s well balanced, strong and reliable, and can run for over an hour on high power without needing its tank refilled. The four-stroke engine is quieter than a two-stroke unit, so far better for working in residential areas.
If you’re fairly tall and need to keep a large area of long grass and weeds under control, this machine is ideal.
Unlike other sites, we thoroughly test every product we review. We use industry standard tests in order to compare features properly. We’ll always tell you what we find. We never, ever accept money to review a product. Tell us what you think - send your emails to the Editor.