diff --git a/coding/bit_streams.cpp b/coding/bit_streams.cpp
index 32a05b1a25..deb23a9342 100644
--- a/coding/bit_streams.cpp
+++ b/coding/bit_streams.cpp
@@ -14,20 +14,30 @@ BitSink::~BitSink()
 void BitSink::Write(uint64_t bits, uint32_t writeSize)
 {
   if (writeSize == 0) return;
+  CHECK_LESS_OR_EQUAL(writeSize, 64, ());
   m_totalBits += writeSize;
   uint32_t remSize = m_size % 8;
-  CHECK_LESS_OR_EQUAL(writeSize, 64 - remSize, ());
-  if (remSize > 0)
+  if (writeSize > 64 - remSize)
   {
-    bits <<= remSize;
-    bits |= m_lastByte;
-    writeSize += remSize;
-    m_size -= remSize;
+    uint64_t writeData = (bits << remSize) | m_lastByte;
+    m_writer.Write(&writeData, sizeof(writeData));
+    m_lastByte = uint8_t(bits >> (64 - remSize));
+    m_size += writeSize;
+  }
+  else
+  {
+    if (remSize > 0)
+    {
+      bits <<= remSize;
+      bits |= m_lastByte;
+      writeSize += remSize;
+      m_size -= remSize;
+    }
+    uint32_t writeBytesSize = writeSize / 8;
+    m_writer.Write(&bits, writeBytesSize);
+    m_lastByte = (bits >> (writeBytesSize * 8)) & ((1 << (writeSize % 8)) - 1);
+    m_size += writeSize;
   }
-  uint32_t writeBytesSize = writeSize / 8;
-  m_writer.Write(&bits, writeBytesSize);
-  m_lastByte = (bits >> (writeBytesSize * 8)) & ((1 << (writeSize % 8)) - 1);
-  m_size += writeSize;
 }
 
 
diff --git a/coding/coding_tests/bit_streams_test.cpp b/coding/coding_tests/bit_streams_test.cpp
index eab3b408d4..730dd23745 100644
--- a/coding/coding_tests/bit_streams_test.cpp
+++ b/coding/coding_tests/bit_streams_test.cpp
@@ -25,7 +25,7 @@ UNIT_TEST(BitStream_ReadWrite)
   vector< pair<uint64_t, uint32_t> > nums;
   for (uint32_t i = 0; i < NUMS_CNT; ++i)
   {
-    uint32_t numBits = GetRand64() % 57;
+    uint32_t numBits = GetRand64() % 65;
     uint64_t num = GetRand64() & (uint64_t(-1) >> (64 - numBits));
     // Right bit shift by 64 doesn't always work correctly,
     // this is a workaround.