diff --git a/grbl/defaults.h b/grbl/defaults.h
index 2489a63..c6cf62e 100644
--- a/grbl/defaults.h
+++ b/grbl/defaults.h
@@ -107,7 +107,7 @@
   #define DEFAULT_SPINDLE_PWM_OFF_VALUE 0   // %
   #define DEFAULT_SPINDLE_PWM_MIN_VALUE 1   // %
   #define DEFAULT_SPINDLE_PWM_MAX_VALUE 100 // %
-  #define DEFAULT_SPINDLE_RPM_MAX 1000.0    // rpm (S-value)
+  #define DEFAULT_SPINDLE_RPM_MAX 300.0    // rpm (S-value)
   #define DEFAULT_SPINDLE_RPM_MIN 0.0       // rpm (S-value)
   #define DEFAULT_STEP_PULSE_MICROSECONDS 10
   #define DEFAULT_STEPPING_INVERT_MASK 0