Monster 659 Owner's Manual page 68

ABS device (for Monster 659 ABS only)
Check that the front (1) and rear (2) phonic wheels are clean.
Warning
Clogged reading slots would compromise system
proper operation.
It is recommended to disable ABS system in case of muddy
road surface because under this condition the system might
be subject to sudden failure.
Warning
Prolonged rearing could deactivate the ABS system.
1
2
E
fig. 56
fig. 57
67