How bad is it? Ive just had mine fail but took it apart, cleaned it ,replaced brushes(4) and springs, reshimmed it to take out the end float and its like a new one . Its fiddly but massively cheaper than a used one which may well need refurb anyway. I would also recommend strongly that you do the starter clutch as well if it hasnt already been apart. If the starter is worn the clutch probably is too!