Deciding whether to shell out the cash for a forage harvester for a machine that simply mows and conditions the grass requires careful balancing of the books.
That’s why Nick Hoyles of Lancashire-based Hoyles Contracting spent a lot of time calculating running costs before deciding to invest in his first Krone Big M.
Due to their purchase price, these machines still have a relatively large place in the UK, but in Ireland, where weed is in their blood, they sell in huge numbers.
Eager to learn more, Mr. Hoyles traveled to the Emerald Isle to see the machines in action and interview fellow entrepreneurs about the economy.
See also: Driver’s View: Krone EasyCut B870 CV Mowers by Stuart Wilson
He was seriously impressed with the performance and his research concluded that a minimum of 2,000 ha of mowing was needed to justify buying a new model.
Hoyles Contracting cuts an area considerably larger than that, so the Big M seemed like a viable option.
However, rather than jump straight into the new market, Mr Hoyles found a 2015 Big M 420 which had just 800 hours on the clock and, at £175,000, was a huge saving.
He raced the 420 for three seasons, which was long enough to convince him that running an extra set of triple mowers made sense.
At this point, his local dealer, Carrs Billington, had a well-specified stock 450 that was attractively priced and came with a three-year warranty.
Switching to the new model seemed profitable and gave him the ability to fix his costs.
His plan is to keep it until the end of the warranty period, after which he will decide whether it makes financial sense to change it or get a few more years of work out of it.
The company also has two sets of triple mowers that are deployed when multiple customers want their grass cut at the same time.
However, they are trying to push as much work as possible through the Big M, aiming to hack 3,000 ha per year.
Krone Big M 450 from Hoyles Contracting
- Year 2022
- Hours 360
- Engine 449 hp Liebherr six-cylinder
- Transmission Hydrostatic with four-wheel drive
- Transport speed 40km/h
- Mowers Three disc mower beds with hydraulic suspension
- cutting width 9.9m
- Conditioner V-type steel tooth
- Groupers Auger type
- Front/rear axle suspension hydropneumatic
- transport width 3m
- transport height 4m
Big M v triple
When the first Big M arrived, Mr. Hoyles and rider Matt “Chippy” Chippendale noticed a significant improvement in production over their larger triples.
“The speed was slightly faster on the straights, but we saved a lot of time on the headlands because the Big M can loop in one and go straight to the next round,” says Hoyles.
Other benefits include the mowers always being mounted and ready to go, the holding is much more maneuverable in small fields and the engine has a combine type air filter which means it does not heat up.
“When we’re running tractors with a set of triples in ratty grass, we’re always trying to keep them cool and seem to be stopping all the time to clean the radiator screens,” says Chippendale.
“With the Big M you can run for several days in the dirtiest conditions without going near the cooling pack – I blow it out every week, but that’s a maintenance job rather than a reaction to it overheating. “
The smooth ride, elevated driving position and quiet cabin are also welcome upgrades over lawn tractors.
“When I come back to the triples I really notice the buzz of the mowers and I’m pretty fed up at the end of the day – the Big M is a much more relaxing place.”
Both Hoyles Big M’s were fitted with auger groups which allow the entire 9.9m working width to be packed into a single row.
These are rarely used in heavy crops, but for lighter stands they sometimes build taller rows to prevent the grass from drying out too quickly.
However, they still use the outside grouper when cutting the headland so that it pulls the grass away from the hedge or fence, making life easier for the rake operator.
Because the engine is so powerful and rarely pushed to its limits, the Big M also uses less fuel per acre than the farm’s John Deere tractors with three mowers.
“The 450 averages about three liters/acre and I can approach two liters in a light crop,” says Chippendale.
The obvious disadvantage of a self-propelled mower is that there is no spare tractor available to do other work outside of the mowing season.
That said, since most of the company’s work is grass-centric, there aren’t many off-season duties for a tractor large enough to run a 9.9m mower set.
“A tractor of this size and a good set of mowers come close to the value of a Big M, so unless there’s a lot of profitable work for the tractor to do when it’s not mowing, I don’t see really the advantage of going in this direction,” says Hoyles.
“Also, once you’ve used a Big M, it’s very difficult to go back to lawn tractors,” he adds.
Benefits of the 450
Upgrading from the Big M 420 to the 450 has resulted in a significant increase in output, with the working width increasing from 9.7m to 9.9m and the maximum mowing speed increasing from 20km/h to 25km/h. h.
Changing from a 423hp MAN engine to a 449hp Liebherr engine also means it can maintain yield in the heaviest grass crops.
But one of the biggest productivity gains has been the addition of automatic GPS guidance, which means the mowers can be steered the full width on every pass.
Since the Hoyles use John Deere tractors, they opted for a Greenstar system that integrates with Krone’s software so it can be activated with a button on the joystick.
All of these improvements mean that a peak output of 16ha/hour is possible, with the average sitting at 10-12ha/hour – a good 1-1.5ha/hour more than the 420.
Mowing quality has also improved thanks to a system of hydraulic floats on the decks which gives a “boulodrome” finish.
“I like that I can adjust the pressure from the cab to get the right amount of float for the conditions,” says Chippendale.
The 420 had spring-loaded mower decks, which got a decent finish, but were less consistent.
In addition, there are fewer misfires between beds on slopes, thanks to a more sophisticated sideshift system for the front mower.
This now moves automatically to counteract the slope and has a mirror function so it moves around headland turns, meaning it’s already in the right position to cut into the other way.
Crop flow has been improved by switching to end-drive rather than center-drive mower beds, which prevents grass from stalling on the center gearbox guard as it shifts to through the mower and results in a smoother swath.
The cab is also a higher quality, with better soundproofing, a higher mounting position and a touch screen to adjust the machine and monitor performance.
As the 450 has yet to reach 500 hours, it’s hard to comment on reliability, but there were a few start-up issues, such as a cracked belt tensioner, faulty front mower gearbox, and slipping clutch questionable on the right mower.
However, these were quickly replaced by the dealership and didn’t stop them for long.
Like any machine, the Big M can still be improved. One of them is the design of the rear lights, which protrude from the wheels when cornering and break easily when caught.
They are mounted on a horizontal swing arm, which Mr Hoyle says should be replaced with a vertical fold that can be operated from the cabin.
Other bugbears are the fact that the large hood leads to poor rear visibility and there is no speed steering feature.
“The turning radius is great, but I have to turn the wheel about four times to turn on the headland and it would be handy if there was an option to reduce it, as is the case on our tractors” , says Mr. Chippendale.