my girlfriend is 5ft 3 and she can't comfortably ride my bike with a 54st, even with post slammed. But of course, everyones different! measure the centre BB to top of saddle (mid point) on her current bike to get an idea of what you'll need. I'd be a little more concerned with the reach though, unless you are going with a short stem and swept back bars?
If you are building with drops and levers, I recently purchased some Tektro RL320 Junior levers for the GFs bike - made a huge difference and she can easily use the brakes from the hoods.
my girlfriend is 5ft 3 and she can't comfortably ride my bike with a 54st, even with post slammed. But of course, everyones different! measure the centre BB to top of saddle (mid point) on her current bike to get an idea of what you'll need. I'd be a little more concerned with the reach though, unless you are going with a short stem and swept back bars?
If you are building with drops and levers, I recently purchased some Tektro RL320 Junior levers for the GFs bike - made a huge difference and she can easily use the brakes from the hoods.