Bike design chooser?

[Shootist]

My sister (aged 68) is looking to buy a new hybrid road bike for causal riding (no off road). She has a pretty good one already, but over a year of use has seemed to highlight apparent flaws in it's design as far as it's relevant to her. As she's been looking around she has noted that many dealers seem to want her to buy a 17" frame, but she seems to feel better on a 19" frame, although she has not ridden one for any distance at all.

What I'm looking for is some sort of decent software/web program that can show variations. Ideally it would then recommend different bike models. I know that bike design is complex, but there are some obvious differences, such as the angle of the seat post/upright tube, and the length of the various other tubes, handlebars etc.

The sort of bike my sister feels she wants is a more traditional 'sit up and beg' style with North Road style handlebars for a comfortable ride without, as far as is possible, leaning forward. Plenty gears are desirable due to slightly aged legs (I hope she doesn't read this!).

All contributions gratefully received.

[gregoryoftours]

I haven't got any suggestions for software, but a bike suggestion - I work for a community bike loan scheme and we loan out dawes mojave bikes. They give a pretty upright riding position and have swept back bars and adjustable stem. 7sp and triple, with a big 34t bottom sprocket on back. Cheapest place online seems to be- http://www.bikes2udirect.com/B5447.html ... wwodqqoAjw
They are not bad for that price and come with full mudguards and good pannier rack. Like any relatively cheap bikes there are parts that aren't so good - namely the wheels in this case. The spoke tension isn't great on some of them, but if you're a little handy with a spoke key you can sort them out pretty easily and bring them up to a suitable tension. Also they have a freewheel rather than freehub which puts more strain on the rear axle. But generally I'd say they are decent enough bikes at a good price, and in my experience come out of the box with grease in the right places etc.

[gregoryoftours]

winstanleys do them in 19" at that price too.
http://www.winstanleysbikes.co.uk/produ ... tAodo30Aog

[531colin]

Many manufacturers don't publish the geometry of this sort of bike, or they only publish partial information, or they change it every year, so actually compiling the data would be a Herculean task. Even if you had all the data to hand, how would you arrive at a recommendation of one bike over another? If, for example, the customer had requirements for a low bottom bracket and a short reach, would you recommend a bike with a short reach and high BB over a bike with a low BB and a long reach?

In practical terms, most of the "rider fit" differences between bikes can be overridden by component choices and adjustments. (the exceptions are bottom bracket height and toe/mudguard clearance, where there is little you can do, apart from tyre size and crank length) A different saddle or seatpost will get you sitting further forward or back. A different stem or handlebar will get your hands higher, lower, further forward or back. In your example, its unlikely that there is as much as an inch difference in the "length" of the frame between a 17" and 19" size of the same bike.

What are the "design flaws" in her current bike?
...... a few guesses.....
....doesn't like sliding off the saddle to get her foot down
....her hands/wrists/ hurt
.....her neck/back hurts
....she wobbles when she signals or looks behind