extra space for clef change

[Stefan Thomas]

Dear lilypond users,
how can I add extra-space before a clef-change?
Here is a short example:

%%%%begin%%%%

\version "2.11.42"
re = \change Staff = rechts
li = \change Staff = links
kleiner = {\set fontSize = #-3 \override DynamicText #'font-size = #+3 } 

normal = {\unset fontSize \revert DynamicText #'font-size } 

manualBeam =
#(define-music-function (parser location beg end)
                        (number? number?)
#{
  \once \override Beam #'positions = #(cons $beg $end)
#})
rechts = \relative { \time 5/4 \compressMusic #'(40 . 47){\kleiner \li \manualBeam #14 #14 <ges aes bes>32[ c \re \clef treble ees a, <fis' gis ais> b,! c'32 ]\li 
    \normal <e,, g>8~ <e g> ~ <e g>1 |}  }
links= { \clef bass s1 s4 }

\score { \new PianoStaff 
    << \new Staff= "rechts" { \rechts }
       \new Staff= "links" { \links} >>
       \layout {
       ragged-right= ##t }
}
%%%% END%%%%%%%%%