diff --git a/src/spfx.c b/src/spfx.c
index 0bfe905..e13d07f 100644
--- a/src/spfx.c
+++ b/src/spfx.c
@@ -226,7 +226,7 @@ void spfx_start(double dt) {
 
 /* Add ruuumble!! */
 void spfx_shake(double mod) {
-  shake_rad += mod;
+  shake_rad += mod/5.;
   if(shake_rad > SHAKE_MAX) shake_rad = SHAKE_MAX;
   shake_off = 0;