Estimating frame size for woman's bike

[LittleGreyCat]

We have friends visiting from abroad later in the year.
The woman is 6 foot tall.
Is it possible to estimate a frame size required from this alone?

I have seen a bike with (I am told) a 24" frame which is roughly 60 cms (which would be OK for a 6 foot male in a man's bike) but I've no idea if that is a comparable guide.

[531colin]

Get her to measure the bike she has at home?

[Barrowman]

Inside leg measurement might help. The old school method for sizing a frame with a horizontal top tube was inside leg minus 7" for cranks and 2" for seatpin if memory serves. Of course dropped top tubes, Mixte etc can have an influence here.
You can have 2 people who are of equal height, one may have short legs and a long body, the other vice versa .

[wirral_cyclist]

Get her to measure her own bike fairly accurately. When we hire bikes abroad we take our own saddles and pedals and then duplicate our own bike dimensions.
So saddle nose to drop tops/hoods, saddle top to BB, drop tops/hoods to BB. Cranks don't matter much as we both ride 170 and 5mm either way seems fine, most bikes seem to be 170. We also measure the virtual seat tube through saddle intersection point, just in case seat pin is really odd offset (or straight). That will usually gets a good fit on anything from a 56 to a 60 for me (leggy 6'2").

Bike size might not matter much if it's only a bit of idle riding but if say touring then measure everything!
I'd say 58-60 are right ball park, I have a frame in each size and my on bike dimensions are identical, as stem and bars take care of reach and bar height that the frame size could affect.

[foxyrider]

Get her to measure the bike she has at home?

wot he said!

[LittleGreyCat]

Unfortunately the measurements I have don't seem to equate to a UK frame size.

I will have to find time to measure the prospective bike in imperial and metric and then ask her to compare.

[Sweep]

Unfortunately the measurements I have don't seem to equate to a UK frame size.

I will have to find time to measure the prospective bike in imperial and metric and then ask her to compare.

Frame size not critical though surely within reason.
As others have said it's really a matter of reproducing key measurements.
I have bikes of all frame sizes including at least one that in theory should be way too big but in practice is just fine.
Hint - you only need to measure once of course no probs to convert imperial/metric.

[foxyrider]

Unfortunately the measurements I have don't seem to equate to a UK frame size.

I will have to find time to measure the prospective bike in imperial and metric and then ask her to compare.

Its not about frame dimensions but all to do with 'cockpit' dimensions, the most important one being pedal to top of saddle. Get that figure and you'll be most of the way to getting the right size, its not the same as inside leg but its close enough to get ball park sizing. I'm hiring a bike in a few weeks and that was the only measurement they wanted, from that and my height the mfr's size chart sat me on an M which is what i had expected and worked out myself. Different brands have their own sizing range so L in one may be XL in another and physical frame measurements are rarely used. I ride bikes with frames measured 52cm to 64cm but the pedal/saddle length is always the same.

good luck