--- a/src/OptionHandlerFactory.cc
+++ b/src/OptionHandlerFactory.cc
@@ -419,7 +419,7 @@ std::vector<OptionHandler*> OptionHandlerFactory::createOptionHandlers()
   {
     OptionHandler* op(new NumberOptionHandler(PREF_MAX_CONNECTION_PER_SERVER,
                                               TEXT_MAX_CONNECTION_PER_SERVER,
-                                              "1", 1, 16, 'x'));
+                                              "128", 1, -1, 'x'));
     op->addTag(TAG_BASIC);
     op->addTag(TAG_FTP);
     op->addTag(TAG_HTTP);
@@ -480,7 +480,7 @@ std::vector<OptionHandler*> OptionHandlerFactory::createOptionHandlers()
   }
   {
     OptionHandler* op(new UnitNumberOptionHandler(
-        PREF_MIN_SPLIT_SIZE, TEXT_MIN_SPLIT_SIZE, "20M", 1_m, 1_g, 'k'));
+        PREF_MIN_SPLIT_SIZE, TEXT_MIN_SPLIT_SIZE, "1M", 1_m, 1_g, 'k'));
     op->addTag(TAG_BASIC);
     op->addTag(TAG_FTP);
     op->addTag(TAG_HTTP);
@@ -791,7 +791,7 @@ std::vector<OptionHandler*> OptionHandlerFactory::createOptionHandlers()
   }
   {
     OptionHandler* op(new NumberOptionHandler(
-        PREF_CONNECT_TIMEOUT, TEXT_CONNECT_TIMEOUT, "60", 1, 600));
+        PREF_CONNECT_TIMEOUT, TEXT_CONNECT_TIMEOUT, "30", 1, 600));
     op->addTag(TAG_FTP);
     op->addTag(TAG_HTTP);
     op->setInitialOption(true);
@@ -862,7 +862,7 @@ std::vector<OptionHandler*> OptionHandlerFactory::createOptionHandlers()
   }
   {
     OptionHandler* op(new UnitNumberOptionHandler(
-        PREF_PIECE_LENGTH, TEXT_PIECE_LENGTH, "1M", 1_m, 1_g));
+        PREF_PIECE_LENGTH, TEXT_PIECE_LENGTH, "1M", 1_m, 1_g));
     op->addTag(TAG_ADVANCED);
     op->addTag(TAG_FTP);
     op->addTag(TAG_HTTP);
@@ -883,7 +883,7 @@ std::vector<OptionHandler*> OptionHandlerFactory::createOptionHandlers()
   }
   {
     OptionHandler* op(
-        new NumberOptionHandler(PREF_RETRY_WAIT, TEXT_RETRY_WAIT, "0", 0, 600));
+        new NumberOptionHandler(PREF_RETRY_WAIT, TEXT_RETRY_WAIT, "2", 0, 600));
     op->addTag(TAG_FTP);
     op->addTag(TAG_HTTP);
     op->setInitialOption(true);
@@ -928,7 +928,7 @@ std::vector<OptionHandler*> OptionHandlerFactory::createOptionHandlers()
   }
   {
     OptionHandler* op(
-        new NumberOptionHandler(PREF_SPLIT, TEXT_SPLIT, "5", 1, -1, 's'));
+        new NumberOptionHandler(PREF_SPLIT, TEXT_SPLIT, "8", 1, -1, 's'));
     op->addTag(TAG_BASIC);
     op->addTag(TAG_FTP);
     op->addTag(TAG_HTTP);