diff --git a/dynamixel_sdk/src/dynamixel_sdk/GroupBulkRead.cpp b/dynamixel_sdk/src/dynamixel_sdk/GroupBulkRead.cpp
index d8f2b6d..f248ee8 100644
--- a/dynamixel_sdk/src/dynamixel_sdk/GroupBulkRead.cpp
+++ b/dynamixel_sdk/src/dynamixel_sdk/GroupBulkRead.cpp
@@ -90,11 +90,11 @@ void GroupBulkRead::RemoveParam(UINT8_T id)
 
 void GroupBulkRead::ClearParam()
 {
-    if(id_list_.size() != 0)
-    {
-        for(unsigned int _i = 0; _i < id_list_.size(); _i++)
-            delete[] data_list_[id_list_[_i]];
-    }
+    if(id_list_.size() == 0)
+        return;
+
+    for(unsigned int _i = 0; _i < id_list_.size(); _i++)
+        delete[] data_list_[id_list_[_i]];
 
     id_list_.clear();
     address_list_.clear();
diff --git a/dynamixel_sdk/src/dynamixel_sdk/GroupBulkWrite.cpp b/dynamixel_sdk/src/dynamixel_sdk/GroupBulkWrite.cpp
index 399b32e..973793b 100644
--- a/dynamixel_sdk/src/dynamixel_sdk/GroupBulkWrite.cpp
+++ b/dynamixel_sdk/src/dynamixel_sdk/GroupBulkWrite.cpp
@@ -111,14 +111,11 @@ bool GroupBulkWrite::ChangeParam(UINT8_T id, UINT16_T start_address, UINT16_T da
 }
 void GroupBulkWrite::ClearParam()
 {
-    if(ph_->GetProtocolVersion() == 1.0)
+    if(ph_->GetProtocolVersion() == 1.0 || id_list_.size() == 0)
         return;
 
-    if(id_list_.size() != 0)
-    {
-        for(unsigned int _i = 0; _i < id_list_.size(); _i++)
-            delete[] data_list_[id_list_[_i]];
-    }
+    for(unsigned int _i = 0; _i < id_list_.size(); _i++)
+        delete[] data_list_[id_list_[_i]];
 
     id_list_.clear();
     address_list_.clear();
diff --git a/dynamixel_sdk/src/dynamixel_sdk/GroupSyncRead.cpp b/dynamixel_sdk/src/dynamixel_sdk/GroupSyncRead.cpp
index 8e602e3..fede283 100644
--- a/dynamixel_sdk/src/dynamixel_sdk/GroupSyncRead.cpp
+++ b/dynamixel_sdk/src/dynamixel_sdk/GroupSyncRead.cpp
@@ -72,14 +72,11 @@ void GroupSyncRead::RemoveParam(UINT8_T id)
 }
 void GroupSyncRead::ClearParam()
 {
-    if(ph_->GetProtocolVersion() == 1.0)
+    if(ph_->GetProtocolVersion() == 1.0 || id_list_.size() == 0)
         return;
 
-    if(id_list_.size() != 0)
-    {
-        for(unsigned int _i = 0; _i < id_list_.size(); _i++)
-            delete[] data_list_[id_list_[_i]];
-    }
+    for(unsigned int _i = 0; _i < id_list_.size(); _i++)
+        delete[] data_list_[id_list_[_i]];
 
     id_list_.clear();
     data_list_.clear();
diff --git a/dynamixel_sdk/src/dynamixel_sdk/GroupSyncWrite.cpp b/dynamixel_sdk/src/dynamixel_sdk/GroupSyncWrite.cpp
index 45d90f8..8a61435 100644
--- a/dynamixel_sdk/src/dynamixel_sdk/GroupSyncWrite.cpp
+++ b/dynamixel_sdk/src/dynamixel_sdk/GroupSyncWrite.cpp
@@ -92,11 +92,11 @@ bool GroupSyncWrite::ChangeParam(UINT8_T id, UINT8_T *data)
 
 void GroupSyncWrite::ClearParam()
 {
-    if(id_list_.size() != 0)
-    {
-        for(unsigned int _i = 0; _i < id_list_.size(); _i++)
-            delete[] data_list_[id_list_[_i]];
-    }
+    if(id_list_.size() == 0)
+        return;
+
+    for(unsigned int _i = 0; _i < id_list_.size(); _i++)
+        delete[] data_list_[id_list_[_i]];
 
     id_list_.clear();
     data_list_.clear();