diff --git a/include/etl/private/bitset_new.h b/include/etl/private/bitset_new.h
index 7d2b2679..ba397209 100644
--- a/include/etl/private/bitset_new.h
+++ b/include/etl/private/bitset_new.h
@@ -665,19 +665,11 @@ namespace etl
       *lhs_pbuffer ^= *rhs_pbuffer;
     }
 
-    //*************************************************************************
-    /// operator ~
-    /// NOT the value in the buffer
-    //*************************************************************************
-    static ETL_CONSTEXPR14 void operator_not(pointer pbuffer, size_t /*number_of_elements*/) ETL_NOEXCEPT
-    {
-      *pbuffer = ~*pbuffer;
-    }
-
     //*************************************************************************
     /// operator_shift_left
     //*************************************************************************
-    static ETL_CONSTEXPR14 void operator_shift_left(pointer pbuffer, size_t /*number_of_elements*/, size_t active_bits, size_t shift) ETL_NOEXCEPT
+    static ETL_CONSTEXPR14 void operator_shift_left(pointer pbuffer, size_t /*number_of_elements*/, size_t active_bits, size_t shift,
+                                             element_type top_mask) ETL_NOEXCEPT
     {
       if (shift >= active_bits)
       {
@@ -686,6 +678,7 @@ namespace etl
       else
       {
         *pbuffer <<= shift;
+        *pbuffer &= top_mask;
       }
     }
 
@@ -716,9 +709,10 @@ namespace etl
     /// Initialise from an unsigned long long.
     //*************************************************************************
     template <typename TElementType>
-    static ETL_CONSTEXPR14 void initialise(pointer pbuffer, size_t /*number_of_elements*/, unsigned long long value) ETL_NOEXCEPT
+    static ETL_CONSTEXPR14 void initialise(pointer pbuffer, size_t /*number_of_elements*/, unsigned long long value, TElementType top_mask)
+      ETL_NOEXCEPT
     {
-      *pbuffer = static_cast<TElementType>(value);
+      *pbuffer = static_cast<TElementType>(value) & top_mask;
     }
 
     //*************************************************************************
@@ -1405,7 +1399,8 @@ namespace etl
     //*************************************************************************
     /// operator_shift_left
     //*************************************************************************
-    static ETL_CONSTEXPR14 void operator_shift_left(pointer pbuffer, size_t number_of_elements, size_t active_bits, size_t shift) ETL_NOEXCEPT
+    static ETL_CONSTEXPR14 void operator_shift_left(pointer pbuffer, size_t number_of_elements, size_t active_bits, size_t shift,
+                                             element_type top_mask) ETL_NOEXCEPT
     {
       if (shift >= active_bits)
       {
@@ -1458,6 +1453,8 @@ namespace etl
         {
           pbuffer[i] = 0;
         }
+
+        pbuffer[(number_of_elements - 1U)] &= top_mask;
       }
     }
 
@@ -1538,7 +1535,7 @@ namespace etl
     template <typename TElementType>
     static
       ETL_CONSTEXPR14 typename etl::enable_if< etl::integral_limits<TElementType>::bits == etl::integral_limits<unsigned long long>::bits, void>::type
-      initialise(pointer pbuffer, size_t number_of_elements, unsigned long long value) ETL_NOEXCEPT
+      initialise(pointer pbuffer, size_t number_of_elements, unsigned long long value, TElementType top_mask) ETL_NOEXCEPT
     {
       size_t i = 0UL;
 
@@ -1550,6 +1547,8 @@ namespace etl
       {
         pbuffer[i++] = All_Clear_Element;
       }
+
+      pbuffer[number_of_elements - 1] &= top_mask;
     }
 
     //*************************************************************************
@@ -1560,7 +1559,7 @@ namespace etl
     template <typename TElementType>
     static
       ETL_CONSTEXPR14 typename etl::enable_if< etl::integral_limits<TElementType>::bits != etl::integral_limits<unsigned long long>::bits, void>::type
-      initialise(pointer pbuffer, size_t number_of_elements, unsigned long long value) ETL_NOEXCEPT
+      initialise(pointer pbuffer, size_t number_of_elements, unsigned long long value, element_type top_mask) ETL_NOEXCEPT
     {
       size_t i = 0UL;
 
@@ -1578,6 +1577,8 @@ namespace etl
       {
         pbuffer[i++] = All_Clear_Element;
       }
+
+      pbuffer[number_of_elements - 1] &= top_mask;
     }
 
     //*************************************************************************
@@ -1810,7 +1811,7 @@ namespace etl
     ETL_CONSTEXPR14 bitset(TValue value, typename etl::enable_if<is_integral<TValue>::value>::type* = 0) ETL_NOEXCEPT
       : buffer()
     {
-      implementation::template initialise<element_type>(buffer, Number_Of_Elements, static_cast<unsigned long long>(value));
+      implementation::template initialise<element_type>(buffer, Number_Of_Elements, static_cast<unsigned long long>(value), Top_Mask);
     }
 
     //*************************************************************************
@@ -2396,7 +2397,7 @@ namespace etl
     {
       etl::bitset<Active_Bits, TElement> temp(*this);
 
-      implementation::operator_shift_left(temp.buffer, Number_Of_Elements, Active_Bits, shift);
+      implementation::operator_shift_left(temp.buffer, Number_Of_Elements, Active_Bits, shift, Top_Mask);
 
       return temp;
     }
@@ -2412,7 +2413,7 @@ namespace etl
       }
       else
       {
-        implementation::operator_shift_left(buffer, Number_Of_Elements, Active_Bits, shift);
+        implementation::operator_shift_left(buffer, Number_Of_Elements, Active_Bits, shift, Top_Mask);
       }
 
       return *this;
@@ -2749,7 +2750,7 @@ namespace etl
       : pbuffer(pbuffer_)
     {
       ETL_ASSERT(pbuffer != ETL_NULLPTR, ETL_ERROR(etl::bitset_invalid_buffer));
-      implementation::template initialise<element_type>(pbuffer, Number_Of_Elements, value);
+      implementation::template initialise<element_type>(pbuffer, Number_Of_Elements, value, Top_Mask);
     }
 
     //*************************************************************************
@@ -2759,7 +2760,7 @@ namespace etl
     ETL_CONSTEXPR14 bitset_ext(TValue value, buffer_type& buffer, typename etl::enable_if<is_integral<TValue>::value>::type* = 0) ETL_NOEXCEPT
       : pbuffer(buffer.data())
     {
-      implementation::template initialise<element_type>(pbuffer, Number_Of_Elements, static_cast<unsigned long long>(value));
+      implementation::template initialise<element_type>(pbuffer, Number_Of_Elements, static_cast<unsigned long long>(value), Top_Mask);
     }
 
     //*************************************************************************
@@ -3343,7 +3344,7 @@ namespace etl
     //*************************************************************************
     ETL_CONSTEXPR14 bitset_ext<Active_Bits, TElement>& operator<<=(size_t shift) ETL_NOEXCEPT
     {
-      implementation::operator_shift_left(pbuffer, Number_Of_Elements, Active_Bits, shift);
+      implementation::operator_shift_left(pbuffer, Number_Of_Elements, Active_Bits, shift, Top_Mask);
 
       return *this;
     }
diff --git a/test/test_bitset_new_default_element_type.cpp b/test/test_bitset_new_default_element_type.cpp
index 0321519b..a1d12e77 100644
--- a/test/test_bitset_new_default_element_type.cpp
+++ b/test/test_bitset_new_default_element_type.cpp
@@ -311,7 +311,7 @@ namespace
         CHECK_EQUAL(compare.test(i), data.test(i));
       }
 
-      CHECK_EQUAL(compare.to_ullong(), data.to_ullong());
+      CHECK_EQUAL_HEX(compare.to_ullong(), data.to_ullong());
     }
 
     //*************************************************************************
@@ -328,7 +328,7 @@ namespace
         CHECK_EQUAL(compare.test(i), data.test(i));
       }
 
-      CHECK_EQUAL(compare.to_ullong(), data.to_ullong());
+      CHECK_EQUAL_HEX(compare.to_ullong(), data.to_ullong());
     }
 
     //*************************************************************************
@@ -345,7 +345,7 @@ namespace
         CHECK_EQUAL(compare.test(i), data.test(i));
       }
 
-      CHECK_EQUAL(compare.to_ullong(), data.to_ullong());
+      CHECK_EQUAL_HEX(compare.to_ullong(), data.to_ullong());
     }
 
     //*************************************************************************
@@ -362,7 +362,7 @@ namespace
         CHECK_EQUAL(compare.test(i), data.test(i));
       }
 
-      CHECK_EQUAL(compare.to_ullong(), data.to_ullong());
+      CHECK_EQUAL_HEX(compare.to_ullong(), data.to_ullong());
     }
 
     //*************************************************************************
@@ -379,7 +379,7 @@ namespace
         CHECK_EQUAL(compare.test(i), data.test(i));
       }
 
-      CHECK_EQUAL(compare.to_ullong(), data.to_ullong());
+      CHECK_EQUAL_HEX(compare.to_ullong(), data.to_ullong());
     }
 
     //*************************************************************************
@@ -394,14 +394,12 @@ namespace
       CHECK_EQUAL(compare.any(), data.any());
       CHECK_EQUAL(compare.all(), data.all());
 
-      CHECK_EQUAL_HEX(compare.to_ullong(), data.to_ullong());
-
       for (size_t i = 0UL; i < data.size(); ++i)
       {
         CHECK_EQUAL(compare.test(i), data.test(i));
       }
 
-      CHECK_EQUAL(compare.to_ullong(), data.to_ullong());
+      CHECK_EQUAL_HEX(compare.to_ullong(), data.to_ullong());
     }
 
     //*************************************************************************
@@ -2743,40 +2741,108 @@ namespace
     }
 
     //*************************************************************************
-    TEST(test_issue_497)
+    TEST(test_issue_497_for_flip)
     {
-      etl::bitset<11, uint8_t> bits;
+      const int Size = 11;
+
+      using Bitset = etl::bitset<Size, uint8_t>;
+
+      Bitset bits;
+
+      // Ensure that we are using multiple elements for the bitset.
+      CHECK_TRUE(Bitset::Number_Of_Elements > 1);
 
       // Check the initial state of the bitset.
-      size_t count_set  = bits.count();
-      size_t count_size = bits.size();
-      bool   all_set    = bits.all();
-
-      CHECK_EQUAL(0, count_set);
-      CHECK_EQUAL(11, count_size);
-      CHECK_EQUAL(false, all_set);
+      CHECK_EQUAL(0, bits.count());
+      CHECK_FALSE(bits.all());
 
       // Copy flipped bits to a new bitset.
-      etl::bitset<11, uint8_t> negated_bits = ~bits;
+      Bitset negated_bits = ~bits;
 
-      count_set  = negated_bits.count();
-      count_size = negated_bits.size();
-      all_set    = negated_bits.all();
-
-      CHECK_EQUAL(11, count_set);
-      CHECK_EQUAL(11, count_size);
-      CHECK_EQUAL(true, all_set);
+      CHECK_EQUAL(Size, negated_bits.count());
+      CHECK_TRUE(negated_bits.all());
 
       // Flip the bits in the original bitset.
       bits.flip();
 
-      count_set  = bits.count();
-      count_size = bits.size();
-      all_set    = bits.all();
+      CHECK_EQUAL(11, bits.count());
+      CHECK_TRUE(bits.all());
+    }
 
-      CHECK_EQUAL(11, count_set);
-      CHECK_EQUAL(11, count_size);
-      CHECK_EQUAL(true, all_set);
+    //*************************************************************************
+    TEST(test_issue_497_for_left_shift)
+    {
+      const int                Size    = 11;
+      const unsigned long long Initial = (1ULL << Size) - 1;
+
+      using Bitset = etl::bitset<Size, uint8_t>;
+
+      // Create a bitset with all bits set to 1.
+      Bitset bits(Initial);
+
+      // Ensure that we are using multiple elements for the bitset.
+      CHECK_TRUE(Bitset::Number_Of_Elements > 1);
+
+      // Check the initial state of the bitset.
+      CHECK_EQUAL(Size, bits.count());
+      CHECK_TRUE(bits.all());
+
+      // The amount to shift so that the value is moved to the msb of the storage.
+      size_t shift_amount = Bitset::Allocated_Bits - Size;
+
+      bits = bits << shift_amount;
+
+      CHECK_EQUAL(Size - shift_amount, bits.count());
+      CHECK_FALSE(bits.all());
+    }
+
+    //*************************************************************************
+    TEST(test_issue_497_for_left_shift_equals)
+    {
+      const int                Size    = 11;
+      const unsigned long long Initial = (1ULL << Size) - 1;
+
+      using Bitset = etl::bitset<Size, uint8_t>;
+
+      // Create a bitset with all bits set to 1.
+      Bitset bits(Initial);
+
+      // Ensure that we are using multiple elements for the bitset.
+      CHECK_TRUE(bits.Number_Of_Elements > 1);
+
+      // Check the initial state of the bitset.
+      CHECK_EQUAL(Size, bits.count());
+      CHECK_TRUE(bits.all());
+
+      // The amount to shift so that the value is moved to the msb of the storage.
+      size_t shift_amount = bits.Allocated_Bits - Size;
+
+      bits <<= shift_amount;
+
+      CHECK_EQUAL(Size - shift_amount, bits.count());
+      CHECK_FALSE(bits.all());
+    }
+
+    //*************************************************************************
+    TEST(test_issue_497_for_initial_value)
+    {
+      const int Size = 11;
+
+      using Bitset = etl::bitset<Size, uint8_t>;
+
+      const unsigned long long Initial = std::numeric_limits<uint16_t>::max();
+      const unsigned long long Expected = ((1ULL << Size) - 1);
+
+      // Create a bitset from a value larger than the bitset size.
+      Bitset bits(Initial);
+
+      // Ensure that we are using multiple elements for the bitset.
+      CHECK_TRUE(Bitset::Number_Of_Elements > 1);
+
+      // Check the initial state of the bitset.
+      CHECK_EQUAL(Expected, bits.to_ullong());
+      CHECK_EQUAL(Size, bits.count());
+      CHECK_TRUE(bits.all());
     }
   }
 } // namespace
diff --git a/test/test_bitset_new_explicit_single_element_type.cpp b/test/test_bitset_new_explicit_single_element_type.cpp
index 3d32174d..abe543d0 100644
--- a/test/test_bitset_new_explicit_single_element_type.cpp
+++ b/test/test_bitset_new_explicit_single_element_type.cpp
@@ -308,7 +308,7 @@ namespace
         CHECK_EQUAL(compare.test(i), data.test(i));
       }
 
-      CHECK_EQUAL(compare.to_ullong(), data.to_ullong());
+      CHECK_EQUAL_HEX(compare.to_ullong(), data.to_ullong());
     }
 
     //*************************************************************************
@@ -325,7 +325,7 @@ namespace
         CHECK_EQUAL(compare.test(i), data.test(i));
       }
 
-      CHECK_EQUAL(compare.to_ullong(), data.to_ullong());
+      CHECK_EQUAL_HEX(compare.to_ullong(), data.to_ullong());
     }
 
     //*************************************************************************
@@ -342,7 +342,7 @@ namespace
         CHECK_EQUAL(compare.test(i), data.test(i));
       }
 
-      CHECK_EQUAL(compare.to_ullong(), data.to_ullong());
+      CHECK_EQUAL_HEX(compare.to_ullong(), data.to_ullong());
     }
 
     //*************************************************************************
@@ -359,14 +359,14 @@ namespace
         CHECK_EQUAL(compare.test(i), data.test(i));
       }
 
-      CHECK_EQUAL(compare.to_ullong(), data.to_ullong());
+      CHECK_EQUAL_HEX(compare.to_ullong(), data.to_ullong());
     }
 
     //*************************************************************************
     TEST(test_construct_from_64_bit_char_string_where_the_bitset_size_is_60)
     {
-      std::bitset<60> compare("110001001000110100010101100111001100010010001101000101011001");
-      etl::bitset<60> data("110001001000110100010101100111001100010010001101000101011001");
+      std::bitset<60>           compare("110001001000110100010101100111001100010010001101000101011001");
+      etl::bitset<60, uint64_t> data("110001001000110100010101100111001100010010001101000101011001");
 
       CHECK_EQUAL(compare.size(), data.size());
       CHECK_EQUAL(compare.count(), data.count());
@@ -376,7 +376,7 @@ namespace
         CHECK_EQUAL(compare.test(i), data.test(i));
       }
 
-      CHECK_EQUAL(compare.to_ullong(), data.to_ullong());
+      CHECK_EQUAL_HEX(compare.to_ullong(), data.to_ullong());
     }
 
     //*************************************************************************
@@ -398,7 +398,7 @@ namespace
         CHECK_EQUAL(compare.test(i), data.test(i));
       }
 
-      CHECK_EQUAL(compare.to_ullong(), data.to_ullong());
+      CHECK_EQUAL_HEX(compare.to_ullong(), data.to_ullong());
     }
 
     //*************************************************************************
@@ -2874,40 +2874,108 @@ namespace
     }
 
     //*************************************************************************
-    TEST(test_issue_497)
+    TEST(test_issue_497_for_flip)
     {
-      etl::bitset<5, uint8_t> bits;
+      const int Size = 11;
+
+      using Bitset = etl::bitset<Size, uint16_t>;
+
+      Bitset bits;
+
+      // Ensure that we are using multiple elements for the bitset.
+      CHECK_TRUE(Bitset::Number_Of_Elements == 1);
 
       // Check the initial state of the bitset.
-      size_t count_set  = bits.count();
-      size_t count_size = bits.size();
-      bool   all_set    = bits.all();
-
-      CHECK_EQUAL(0, count_set);
-      CHECK_EQUAL(5, count_size);
-      CHECK_EQUAL(false, all_set);
+      CHECK_EQUAL(0, bits.count());
+      CHECK_FALSE(bits.all());
 
       // Copy flipped bits to a new bitset.
-      etl::bitset<5, uint8_t> negated_bits = ~bits;
+      Bitset negated_bits = ~bits;
 
-      count_set  = negated_bits.count();
-      count_size = negated_bits.size();
-      all_set    = negated_bits.all();
-
-      CHECK_EQUAL(5, count_set);
-      CHECK_EQUAL(5, count_size);
-      CHECK_EQUAL(true, all_set);
+      CHECK_EQUAL(Size, negated_bits.count());
+      CHECK_TRUE(negated_bits.all());
 
       // Flip the bits in the original bitset.
       bits.flip();
 
-      count_set  = bits.count();
-      count_size = bits.size();
-      all_set    = bits.all();
+      CHECK_EQUAL(11, bits.count());
+      CHECK_TRUE(bits.all());
+    }
 
-      CHECK_EQUAL(5, count_set);
-      CHECK_EQUAL(5, count_size);
-      CHECK_EQUAL(true, all_set);
+    //*************************************************************************
+    TEST(test_issue_497_for_left_shift)
+    {
+      const int                Size    = 11;
+      const unsigned long long Initial = (1ULL << Size) - 1;
+
+      using Bitset = etl::bitset<Size, uint16_t>;
+
+      // Create a bitset with all bits set to 1.
+      Bitset bits(Initial);
+
+      // Ensure that we are using multiple elements for the bitset.
+      CHECK_TRUE(Bitset::Number_Of_Elements == 1);
+
+      // Check the initial state of the bitset.
+      CHECK_EQUAL(Size, bits.count());
+      CHECK_TRUE(bits.all());
+
+      // The amount to shift so that the value is moved to the msb of the storage.
+      size_t shift_amount = Bitset::Allocated_Bits - Size;
+
+      bits = bits << shift_amount;
+
+      CHECK_EQUAL(Size - shift_amount, bits.count());
+      CHECK_FALSE(bits.all());
+    }
+
+    //*************************************************************************
+    TEST(test_issue_497_for_left_shift_equals)
+    {
+      const int                Size    = 11;
+      const unsigned long long Initial = (1ULL << Size) - 1;
+
+      using Bitset = etl::bitset<Size, uint16_t>;
+
+      // Create a bitset with all bits set to 1.
+      Bitset bits(Initial);
+
+      // Ensure that we are using multiple elements for the bitset.
+      CHECK_TRUE(bits.Number_Of_Elements == 1);
+
+      // Check the initial state of the bitset.
+      CHECK_EQUAL(Size, bits.count());
+      CHECK_TRUE(bits.all());
+
+      // The amount to shift so that the value is moved to the msb of the storage.
+      size_t shift_amount = bits.Allocated_Bits - Size;
+
+      bits <<= shift_amount;
+
+      CHECK_EQUAL(Size - shift_amount, bits.count());
+      CHECK_FALSE(bits.all());
+    }
+
+    //*************************************************************************
+    TEST(test_issue_497_for_initial_value)
+    {
+      const int Size = 11;
+
+      using Bitset = etl::bitset<Size, uint16_t>;
+
+      const unsigned long long Initial = std::numeric_limits<uint16_t>::max();
+      const unsigned long long Expected = ((1ULL << Size) - 1);
+
+      // Create a bitset from a value larger than the bitset size.
+      Bitset bits(Initial);
+
+      // Ensure that we are using multiple elements for the bitset.
+      CHECK_TRUE(Bitset::Number_Of_Elements == 1);
+
+      // Check the initial state of the bitset.
+      CHECK_EQUAL(Expected, bits.to_ullong());
+      CHECK_EQUAL(Size, bits.count());
+      CHECK_TRUE(bits.all());
     }
   }
 } // namespace
diff --git a/test/test_bitset_new_ext_default_element_type.cpp b/test/test_bitset_new_ext_default_element_type.cpp
index dfa5c5aa..17f61a69 100644
--- a/test/test_bitset_new_ext_default_element_type.cpp
+++ b/test/test_bitset_new_ext_default_element_type.cpp
@@ -252,7 +252,7 @@ namespace
         CHECK_EQUAL(compare.test(i), data.test(i));
       }
 
-      CHECK_EQUAL(compare.to_ullong(), data.to_ullong());
+      CHECK_EQUAL_HEX(compare.to_ullong(), data.to_ullong());
     }
 
     //*************************************************************************
@@ -270,7 +270,7 @@ namespace
         CHECK_EQUAL(compare.test(i), data.test(i));
       }
 
-      CHECK_EQUAL(compare.to_ullong(), data.to_ullong());
+      CHECK_EQUAL_HEX(compare.to_ullong(), data.to_ullong());
     }
 
     //*************************************************************************
@@ -288,7 +288,7 @@ namespace
         CHECK_EQUAL(compare.test(i), data.test(i));
       }
 
-      CHECK_EQUAL(compare.to_ullong(), data.to_ullong());
+      CHECK_EQUAL_HEX(compare.to_ullong(), data.to_ullong());
     }
 
     //*************************************************************************
@@ -306,7 +306,7 @@ namespace
         CHECK_EQUAL(compare.test(i), data.test(i));
       }
 
-      CHECK_EQUAL(compare.to_ullong(), data.to_ullong());
+      CHECK_EQUAL_HEX(compare.to_ullong(), data.to_ullong());
     }
 
     //*************************************************************************
@@ -324,7 +324,7 @@ namespace
         CHECK_EQUAL(compare.test(i), data.test(i));
       }
 
-      CHECK_EQUAL(compare.to_ullong(), data.to_ullong());
+      CHECK_EQUAL_HEX(compare.to_ullong(), data.to_ullong());
     }
 
     //*************************************************************************
@@ -347,7 +347,7 @@ namespace
         CHECK_EQUAL(compare.test(i), data.test(i));
       }
 
-      CHECK_EQUAL(compare.to_ullong(), data.to_ullong());
+      CHECK_EQUAL_HEX(compare.to_ullong(), data.to_ullong());
     }
 
     //*************************************************************************
@@ -2490,40 +2490,83 @@ namespace
     }
 
     //*************************************************************************
-    TEST(test_issue_497)
+    TEST(test_issue_497_for_flip)
     {
-      etl::bitset_ext<11>::buffer_type buffer1;
-      etl::bitset_ext<11>              bits(buffer1);
+      const int Size = 11;
+
+      using Bitset = etl::bitset_ext<Size, uint8_t>;
+      using Buffer = Bitset::buffer_type;
+
+      Buffer buffer1;
+      Bitset bits(buffer1);
+
+      // Ensure that we are using multiple elements for the bitset.
+      CHECK_TRUE(Bitset::Number_Of_Elements > 1);
 
       // Check the initial state of the bitset.
-      size_t count_set  = bits.count();
-      size_t count_size = bits.size();
-      bool   all_set    = bits.all();
-
-      CHECK_EQUAL(0, count_set);
-      CHECK_EQUAL(11, count_size);
-      CHECK_EQUAL(false, all_set);
+      CHECK_EQUAL(0, bits.count());
+      CHECK_FALSE(bits.all());
 
       // Copy flipped bits to a new bitset.
-      etl::bitset_ext<11>::buffer_type buffer2;
-      etl::bitset_ext<11>              negated_bits(bits.flip(), buffer2);
+      // Copy flipped bits to a new bitset.
+      Buffer buffer2;
+      Bitset negated_bits(bits.flip(), buffer2);
 
-      count_set  = negated_bits.count();
-      count_size = negated_bits.size();
-      all_set    = negated_bits.all();
+      CHECK_EQUAL(Size, negated_bits.count());
+      CHECK_TRUE(negated_bits.all());
+    }
 
-      CHECK_EQUAL(11, count_set);
-      CHECK_EQUAL(11, count_size);
-      CHECK_EQUAL(true, all_set);
+    //*************************************************************************
+    TEST(test_issue_497_for_left_shift_equals)
+    {
+      const int                Size    = 11;
+      const unsigned long long Initial = (1ULL << Size) - 1;
 
-      // Test the flipped the bits in the original bitset.
-      count_set  = bits.count();
-      count_size = bits.size();
-      all_set    = bits.all();
+      using Bitset = etl::bitset_ext<Size, uint8_t>;
+      using Buffer = Bitset::buffer_type;
 
-      CHECK_EQUAL(11, count_set);
-      CHECK_EQUAL(11, count_size);
-      CHECK_EQUAL(true, all_set);
+      // Create a bitset with all bits set to 1.
+      Buffer buffer1;
+      Bitset bits(Initial, buffer1);
+
+      // Ensure that we are using multiple elements for the bitset.
+      CHECK_TRUE(bits.Number_Of_Elements > 1);
+
+      // Check the initial state of the bitset.
+      CHECK_EQUAL(Size, bits.count());
+      CHECK_TRUE(bits.all());
+
+      // The amount to shift so that the value is moved to the msb of the storage.
+      size_t shift_amount = bits.Allocated_Bits - Size;
+
+      bits <<= shift_amount;
+
+      CHECK_EQUAL(Size - shift_amount, bits.count());
+      CHECK_FALSE(bits.all());
+    }
+
+    //*************************************************************************
+    TEST(test_issue_497_for_initial_value)
+    {
+      const int Size = 11;
+
+      using Bitset = etl::bitset_ext<Size, uint8_t>;
+      using Buffer = Bitset::buffer_type;
+
+      const unsigned long long Initial = std::numeric_limits<uint16_t>::max();
+      const unsigned long long Expected = ((1ULL << Size) - 1);
+
+      // Create a bitset from a value larger than the bitset size.
+      Buffer buffer1;
+      Bitset bits(Initial, buffer1);
+
+      // Ensure that we are using multiple elements for the bitset.
+      CHECK_TRUE(Bitset::Number_Of_Elements > 1);
+
+      // Check the initial state of the bitset.
+      CHECK_EQUAL(Expected, bits.to_ullong());
+      CHECK_EQUAL(Size, bits.count());
+      CHECK_TRUE(bits.all());
     }
   }
 } // namespace
diff --git a/test/test_bitset_new_ext_explicit_single_element_type.cpp b/test/test_bitset_new_ext_explicit_single_element_type.cpp
index 889ff78c..42d4003a 100644
--- a/test/test_bitset_new_ext_explicit_single_element_type.cpp
+++ b/test/test_bitset_new_ext_explicit_single_element_type.cpp
@@ -280,7 +280,7 @@ namespace
         CHECK_EQUAL(compare.test(i), data.test(i));
       }
 
-      CHECK_EQUAL(compare.to_ullong(), data.to_ullong());
+      CHECK_EQUAL_HEX(compare.to_ullong(), data.to_ullong());
     }
 
     //*************************************************************************
@@ -298,7 +298,7 @@ namespace
         CHECK_EQUAL(compare.test(i), data.test(i));
       }
 
-      CHECK_EQUAL(compare.to_ullong(), data.to_ullong());
+      CHECK_EQUAL_HEX(compare.to_ullong(), data.to_ullong());
     }
 
     //*************************************************************************
@@ -316,7 +316,7 @@ namespace
         CHECK_EQUAL(compare.test(i), data.test(i));
       }
 
-      CHECK_EQUAL(compare.to_ullong(), data.to_ullong());
+      CHECK_EQUAL_HEX(compare.to_ullong(), data.to_ullong());
     }
 
     //*************************************************************************
@@ -334,7 +334,7 @@ namespace
         CHECK_EQUAL(compare.test(i), data.test(i));
       }
 
-      CHECK_EQUAL(compare.to_ullong(), data.to_ullong());
+      CHECK_EQUAL_HEX(compare.to_ullong(), data.to_ullong());
     }
 
     //*************************************************************************
@@ -352,7 +352,7 @@ namespace
         CHECK_EQUAL(compare.test(i), data.test(i));
       }
 
-      CHECK_EQUAL(compare.to_ullong(), data.to_ullong());
+      CHECK_EQUAL_HEX(compare.to_ullong(), data.to_ullong());
     }
 
     //*************************************************************************
@@ -374,8 +374,6 @@ namespace
       {
         CHECK_EQUAL(compare.test(i), data.test(i));
       }
-
-      CHECK_EQUAL(compare.to_ullong(), data.to_ullong());
     }
 
     //*************************************************************************
@@ -2656,42 +2654,85 @@ namespace
 
       CHECK_EQUAL(32, ETL_OR_STD17::size(b));
     }
-  }
 
-  //*************************************************************************
-  TEST(test_issue_497)
-  {
-    etl::bitset_ext<11, uint8_t>::buffer_type buffer1;
-    etl::bitset_ext<11, uint8_t>              bits(buffer1);
+    //*************************************************************************
+    TEST(test_issue_497_for_flip)
+    {
+      const int Size = 11;
 
-    // Check the initial state of the bitset.
-    size_t count_set  = bits.count();
-    size_t count_size = bits.size();
-    bool   all_set    = bits.all();
+      using Bitset = etl::bitset_ext<Size, uint16_t>;
+      using Buffer = Bitset::buffer_type;
 
-    CHECK_EQUAL(0, count_set);
-    CHECK_EQUAL(11, count_size);
-    CHECK_EQUAL(false, all_set);
+      Buffer buffer1;
+      Bitset bits(buffer1);
 
-    // Copy flipped bits to a new bitset.
-    etl::bitset_ext<11, uint8_t>::buffer_type buffer2;
-    etl::bitset_ext<11, uint8_t>              negated_bits(bits.flip(), buffer2);
+      // Ensure that we are using multiple elements for the bitset.
+      CHECK_TRUE(Bitset::Number_Of_Elements == 1);
 
-    count_set  = negated_bits.count();
-    count_size = negated_bits.size();
-    all_set    = negated_bits.all();
+      // Check the initial state of the bitset.
+      CHECK_EQUAL(0, bits.count());
+      CHECK_FALSE(bits.all());
 
-    CHECK_EQUAL(11, count_set);
-    CHECK_EQUAL(11, count_size);
-    CHECK_EQUAL(true, all_set);
+      // Copy flipped bits to a new bitset.
+      // Copy flipped bits to a new bitset.
+      Buffer buffer2;
+      Bitset negated_bits(bits.flip(), buffer2);
 
-    // Test the flipped the bits in the original bitset.
-    count_set  = bits.count();
-    count_size = bits.size();
-    all_set    = bits.all();
+      CHECK_EQUAL(Size, negated_bits.count());
+      CHECK_TRUE(negated_bits.all());
+    }
 
-    CHECK_EQUAL(11, count_set);
-    CHECK_EQUAL(11, count_size);
-    CHECK_EQUAL(true, all_set);
+    //*************************************************************************
+    TEST(test_issue_497_for_left_shift_equals)
+    {
+      const int                Size    = 11;
+      const unsigned long long Initial = (1ULL << Size) - 1;
+
+      using Bitset = etl::bitset_ext<Size, uint16_t>;
+      using Buffer = Bitset::buffer_type;
+
+      // Create a bitset with all bits set to 1.
+      Buffer buffer1;
+      Bitset bits(Initial, buffer1);
+
+      // Ensure that we are using multiple elements for the bitset.
+      CHECK_TRUE(bits.Number_Of_Elements == 1);
+
+      // Check the initial state of the bitset.
+      CHECK_EQUAL(Size, bits.count());
+      CHECK_TRUE(bits.all());
+
+      // The amount to shift so that the value is moved to the msb of the storage.
+      size_t shift_amount = bits.Allocated_Bits - Size;
+
+      bits <<= shift_amount;
+
+      CHECK_EQUAL(Size - shift_amount, bits.count());
+      CHECK_FALSE(bits.all());
+    }
+
+    //*************************************************************************
+    TEST(test_issue_497_for_initial_value)
+    {
+      const int Size = 11;
+
+      using Bitset = etl::bitset_ext<Size, uint16_t>;
+      using Buffer = Bitset::buffer_type;
+
+      const unsigned long long Initial = std::numeric_limits<uint16_t>::max();
+      const unsigned long long Expected = ((1ULL << Size) - 1);
+
+      // Create a bitset from a value larger than the bitset size.
+      Buffer buffer1;
+      Bitset bits(Initial, buffer1);
+
+      // Ensure that we are using multiple elements for the bitset.
+      CHECK_TRUE(Bitset::Number_Of_Elements == 1);
+
+      // Check the initial state of the bitset.
+      CHECK_EQUAL(Expected, bits.to_ullong());
+      CHECK_EQUAL(Size, bits.count());
+      CHECK_TRUE(bits.all());
+    }
   }
 } // namespace