diff --git a/core/scripts/run-tests.sh b/core/scripts/run-tests.sh
index 9e832a5..7f35ba2 100755
--- a/core/scripts/run-tests.sh
+++ b/core/scripts/run-tests.sh
@@ -141,6 +141,8 @@
 }
 
 $test_list = simpletest_script_get_test_list();
+// Limit to testing only 62 classes.
+$test_list = array_slice($test_list, 0, 62, TRUE);
 
 // Try to allocate unlimited time to run the tests.
 drupal_set_time_limit(0);
