Ground Speed; Cutting Width; Blade Speed - Honda Harmony H2013HDA Owner's Manual

OPERATION
Ground Speed
Keep the shift lever in the MOWING range for best results. Slow the
ground speed of the lawn tractor when mowing taller grass. Always
use the shift lever to control the ground speed, never the throttle.
Cutting Width
Allow an adequate amount of overlap in the cutting
path when mowing. Four to six inches is
recommended; this is roughly the same width as a
front tire.
When overlapping in a curve, use a lower speed, and
overlap the previous cut by 50%, or about half the
width of the mower deck. In extremely tall or thick
grass, you may have to cut a larger overlap.
Blade Speed
LT-AAA
The blades must spin very fast to cut properly. Always use the FAST
throttle setting, and keep the engine running at maximum rpm.
If engine speed drops, it could mean the engine is being overloaded
by the blade trying to cut too much grass. Mow a narrower swath,
operate the lawn tractor at a slower ground speed, or raise the cutting
height of the mower deck.