diff --git a/tests/unit/test_bcd_data_stream.py b/tests/unit/test_bcd_data_stream.py
new file mode 100644
index 000000000..577c0ebf2
--- /dev/null
+++ b/tests/unit/test_bcd_data_stream.py
@@ -0,0 +1,23 @@
+from twisted.trial import unittest
+
+from torba.bcd_data_stream import BCDataStream
+
+
+class TestBCDataStream(unittest.TestCase):
+
+    def test_write_read(self):
+        s = BCDataStream()
+        s.write_string(b'a'*252)
+        s.write_string(b'b'*254)
+        s.write_string(b'c'*(0xFFFF + 1))
+        # s.write_string(b'd'*(0xFFFFFFFF + 1))
+        s.write_boolean(True)
+        s.write_boolean(False)
+        s.reset()
+
+        self.assertEqual(s.read_string(), b'a'*252)
+        self.assertEqual(s.read_string(), b'b'*254)
+        self.assertEqual(s.read_string(), b'c'*(0xFFFF + 1))
+        # self.assertEqual(s.read_string(), b'd'*(0xFFFFFFFF + 1))
+        self.assertEqual(s.read_boolean(), True)
+        self.assertEqual(s.read_boolean(), False)
diff --git a/torba/bcd_data_stream.py b/torba/bcd_data_stream.py
index 1eb602015..ab06cdecc 100644
--- a/torba/bcd_data_stream.py
+++ b/torba/bcd_data_stream.py
@@ -7,10 +7,6 @@ class BCDataStream:
     def __init__(self, data=None):
         self.data = BytesIO(data)
 
-    @property
-    def is_at_beginning(self):
-        return self.data.tell() == 0
-
     def reset(self):
         self.data.seek(0)