\version "2.13.62"
csr = \change Staff = "right"
csl = \change Staff = "left" 

global = {
  \key c \major
}

right = \relative c'' {
  \global
  % Doesn't work: The \change is counted as note, thus a dot is added
  \csl \repeat tremolo 4 { f,,16 \csr f'}
  % Works: Only two notes, correctly scaled:
  \repeat tremolo 4 { f16 f'} |
}


\score {
  \new PianoStaff <<
    \new Staff = "right" \right
    \new Staff = "left" { \clef bass \global \stemDown d,1  }
  >>
}