diff --git a/Periodic_4_hyperbolic_triangulation_2/include/CGAL/Periodic_4_hyperbolic_Delaunay_triangulation_2.h b/Periodic_4_hyperbolic_triangulation_2/include/CGAL/Periodic_4_hyperbolic_Delaunay_triangulation_2.h
index 00f31bd1db2..5d1c4ac8cb4 100644
--- a/Periodic_4_hyperbolic_triangulation_2/include/CGAL/Periodic_4_hyperbolic_Delaunay_triangulation_2.h
+++ b/Periodic_4_hyperbolic_triangulation_2/include/CGAL/Periodic_4_hyperbolic_Delaunay_triangulation_2.h
@@ -406,7 +406,7 @@ is_removable(Vertex_handle v,
   // This is the exact value of the limit.
   // The systole is 2*acosh(1+sqrt(2)), and we want half of that.
   // The max _diameter_ of the hyperbolic circles must be less than this.
-  double factor(0.9); // percentage of the limit to consider -- failsafe!
+  double factor(0.85); // percentage of the limit to consider -- failsafe!
   double lim(factor*acosh(1. + sqrt(2.)));
 
   std::vector<Vertex_handle> bdry_verts;