Combine Harvester: Adjusting to Cut Grain Losses

A combine that is not set for the crop and moisture can lose several percent of yield.

Main settings

• Forward speed: too fast overloads the machine and spills grain.
• Header height and reel speed: cut as low as practical for short crops, and match reel to ground speed.
• Threshing cylinder speed and concave gap: enough to thresh cleanly without cracking grain or breaking straw into fine pieces.
• Fan speed and sieves: enough air to blow out chaff without blowing grain out of the back.

Check losses

Stop and walk behind the machine: count grains on a set area, compare with a reference, and adjust one setting at a time.

Harvest at the right moisture

Standing crop at correct moisture threshes cleanly and stores well; too wet means hard threshing and damage, too dry means shatter.

Sharp knives, good belts and clean sieves help every day.