: Lower speeds are required to prevent grain breakage, often ranging from 400 to 600 RPM .
: If your dashboard tachometer is unreliable, you can use a handheld digital pulse tachometer to verify actual speeds at the pulleys. Zmaj 142 RPM
: As drum RPM increases, cleaning efficiency generally improves, though this must be balanced against the risk of blowing grain out of the back of the machine. Adjustment & Maintenance : Lower speeds are required to prevent grain
: Usually set between 900 and 1100 RPM . Research indicates that maximum threshing efficiency (up to 99.9%) is often achieved at 1100 RPM . cleaning efficiency generally improves