diff --git a/config/tmux/legacy.conf b/config/tmux/legacy.conf
index 562a609..c420806 100644
--- a/config/tmux/legacy.conf
+++ b/config/tmux/legacy.conf
@@ -4,8 +4,11 @@
 
 bind-key -t vi-copy PPage page-up
 bind-key -t vi-copy NPage page-down
-bind-key -t vi-copy WheelUpPane halfpage-up
-bind-key -t vi-copy WheelDownPane halfpage-down
+# Mouse wheel scrolls 4 lines per tick, not tmux's half-page default (20 lines
+# in a 40-line pane). Old bind-key has no -N; -R is the equivalent repeat
+# count for keys in the copy-mode tables.
+bind-key -R 4 -t vi-copy WheelUpPane scroll-up
+bind-key -R 4 -t vi-copy WheelDownPane scroll-down
 bind-key -t vi-copy v begin-selection
 bind-key -t vi-copy y copy-pipe "$HOME/dotfiles/bin/clipboard-copy"
 unbind-key -t vi-copy Enter
diff --git a/config/tmux/modern.conf b/config/tmux/modern.conf
index b377a33..218b1ae 100644
--- a/config/tmux/modern.conf
+++ b/config/tmux/modern.conf
@@ -3,8 +3,11 @@
 
 bind-key -T copy-mode-vi PPage send-keys -X page-up
 bind-key -T copy-mode-vi NPage send-keys -X page-down
-bind-key -T copy-mode-vi WheelUpPane send-keys -X halfpage-up
-bind-key -T copy-mode-vi WheelDownPane send-keys -X halfpage-down
+# Mouse wheel scrolls 4 lines per tick, not tmux's half-page default (20 lines
+# in a 40-line pane). -N is the repeat count; scroll-up/scroll-down take no
+# direct amount argument and tmux resets the count after each command.
+bind-key -T copy-mode-vi WheelUpPane send-keys -X -N 4 scroll-up
+bind-key -T copy-mode-vi WheelDownPane send-keys -X -N 4 scroll-down
 bind-key -T copy-mode-vi v send-keys -X begin-selection
 bind-key -T copy-mode-vi y send-keys -X copy-pipe "$HOME/dotfiles/bin/clipboard-copy"
 unbind-key -T copy-mode-vi Enter