diff --git a/src/calibre/ebooks/metadata/pdb.py b/src/calibre/ebooks/metadata/pdb.py
index ccc64d70aa..ddf2b0c818 100644
--- a/src/calibre/ebooks/metadata/pdb.py
+++ b/src/calibre/ebooks/metadata/pdb.py
@@ -51,5 +51,5 @@ def set_metadata(stream, mi):
         MetadataWriter(stream, mi)
 
     stream.seek(0)
-    stream.write(re.sub('[^-A-Za-z0-9]+', '_', mi.title).ljust(32, '\x00')[:32])
+    stream.write('%s\x00' % re.sub('[^-A-Za-z0-9 ]+', '_', mi.title).ljust(31, '\x00')[:31].encode('ascii', 'replace'))
 
diff --git a/src/calibre/ebooks/pdb/header.py b/src/calibre/ebooks/pdb/header.py
index 75455354c2..3436c262d8 100644
--- a/src/calibre/ebooks/pdb/header.py
+++ b/src/calibre/ebooks/pdb/header.py
@@ -30,7 +30,7 @@ class PdbHeaderReader(object):
 
     def name(self):
         self.stream.seek(0)
-        return re.sub('[^-A-Za-z0-9 ]+', '', self.stream.read(32).replace('\x00', ''))
+        return self.stream.read(32).replace('\x00', '')
 
     def full_section_info(self, number):
         if number not in range(0, self.num_sections):