Some interesting info here so u can work it out:
http://www.ducatisportingclub.com/xm....php?tid=19755 Generally - smaller front = accleration
Larger rear = accleration
small front + large rear = mucho accleration
much better article here (again look for Shazaams post - at the bottom):
http://www.ducatisportingclub.com/xm....php?tid=18755 Frank