It is 25 years since Krone entered the self-propelled market with the Big M mower. Premiered in May, 1996, it was a big success and the 3,545th machine is expected to exit the production line at the end of July this year.
Someone who knows pretty well all there is to know about the Big M is Josef Horstmann, who recalls May 10, 1996, the day journalists got to see the prototype, as the most stressful day of his career.
The machine was due to get a quick wash in the morning, before being presented to the international press in the afternoon. Sadly, on its way to the garage the electrical harness caught fire.
Fortunately, the team managed to repair Big M so that it was able to perform at its afternoon debut. “It all went well, although we weren’t able to demonstrate all of its functions, but nobody noticed,” says Mr Horstman.
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Modern Big Ms are fitted with Fritzmaier cabs, but the structure on the first machines, including this one at the Krone museum in Spelle, was supplied by John Deere.
The press were thrilled. So to were the contractors trialling the Big M, which had a cutting with of 9.10m. “It gave them an enormous efficiency on the one hand and came with a 40km/hr road homologation on the other. So, we actually killed two birds with one stone – maximum efficiency and fast travel between fields.”
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Josef Horstmann was involved with the Big M project from day one.
In 1999, the Big M was subjected to a 24-hour endurance test where it cut 315.1ha in 24 hours and an average of 15.2ha/hr. These two numbers secured an entry in the Guinness Book of Records.
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Launched in 2001, the Big MII (9.7m) was fitted with a new drivetrain that adapted engine speed to forward speed. This helped to reduce fuel consumption and stresses and strains on the engine and drives. These changes helped fuel the popularity and the 500th Big M was sold in May 2003.
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Krone stunned Agritechnica 2007 visitors with the 510hp Big M 500, which boasted a working width of 13.20m. “In hindsight, I think it was a bit ahead of its time, but it did offer a preview of what would be possible in the future,” says Mr Horstmann.
The Big M 500 was phased out, but the popularity of the 9.7m Big M continued, and the 1,000th machine left the Spelle factory in October 2008.
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Next milestone developments included the launch of the 400hp Big M400 at Agritechnica 2009, followed by the MAN-powered Big M420 (fourth generation) in 2011. The fifth generation followed in 2017, the 449hp Liebherr-powered Big M450 model, and the newest model, the Big M 450CR, was launched in 2020.
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“Over the course of 25 years Krone has continued refining the self-propelled mower to today’s professional level,” comments Mr Horstmann, “and the Big M is enjoying sustained popularity especially in Germany, North America, Japan and Ireland.”
“This truly reflects a success story in a very competitive environment in which tractors are becoming ever more powerful and triple mowers keep growing in widths. Despite all the changes one thing is for sure, Big M and its success was instrumental for Krone’s decision to enter the forage harvester segment.”