diff --git a/examples/cluster.c b/examples/cluster.c
index 0023085..3e6d796 100644
--- a/examples/cluster.c
+++ b/examples/cluster.c
@@ -15,15 +15,15 @@ static void draw_needle(cairo_t *cr,
                         double min_angle,
                         double max_angle,
                         double value) {
-    double angle = min_angle + ((max_angle - min_angle) * value) - 90.0;
+    double angle = min_angle + ((max_angle - min_angle) * value) - (M_PI/2);
 
     cairo_move_to(cr, x, y);
 
     cairo_set_source_rgb(cr, 0, 0.25, 1.0);
 
     cairo_line_to(cr,
-                  x + r * cos((M_PI/180.0) * angle),
-                  y + r * sin((M_PI/180.0) * angle));
+                  x + r * cos(angle),
+                  y + r * sin(angle));
 
     cairo_stroke(cr);
 }
@@ -79,7 +79,7 @@ static void draw_tachometer(cairo_t *cr,
     /*
      * Draw a gauge needle
      */
-    draw_needle(cr, x, y, 0.77 * r, 232, 488, 0.0);
+    draw_needle(cr, x, y, 0.77 * r, 232 * (M_PI/180), 488 * (M_PI/180), 0.0);
 
     /*
      * Draw a tiny boi circle