Honda HRS21 Owner's Manual page 18

4. Check the blade bolts for tightness.
Torque: 5.0-6.0 kg-m (36.2-43.4 ft-lb)
m To be certain that the engine will not start accidentally, re-
move the spark plug cap before performing this inspection.
5. Check the air cleaner element and clean it if it is dirty (p.29)
AIR CLEANER
16