women's vs men's bikesMen's bikes differ from women's bikes primarily in frame geometry and subtle yet important differences in handlebars and saddles.  For many years, women cyclists were forced to ride bikes designed for the male physique - that is, for men's proportionately longer torsos, wider shoulders and shorter legs.  Shorter women had to be content with finding extra small men's frames and modifying them to fit (generally with shorter stems).  This often didn't work well, and short women rode in great discomfort or worse, quit the sport.  Men's bikes tend to be too long in the top tube for many women (ever the taller ones).  Riding a too-long bike results in serious discomfort:  common symptoms are neck pain, numb hands, sore lower back and saddle pain.  Additionally, the rider loses power in a stretched out riding position (the torso and arms need to be more compact, not fully extended).

In the past, the only bikes available to women that were classified as "women's bikes" were simply men's bikes with a step-through frame (to accommodate riders in skirts).  Even bikes that were marketed as women's bikes were just smaller versions of men's bikes with "girlie" graphics and paint.  Fortunately, bicycle manufacturers finally came to realize that men and women have different needs, and women comprise half of their customers.  In the past six or seven years, major companies such as Trek and Specialized began making women's specific bikes.

The biggest difference between men's frames and women's frames is top tube length.  This puts the female rider into a much more comfortable and biomechanically efficient position.  Handlebars on a women's bike are narrower to accommodate a woman's narrower shoulders.  Women's bikes come with female-specific saddles which are wider in the seat, to better support a female pelvis.  Very small sizes in women's bikes have shorter crankarms than the standard 172.5mm length (going as low as 150mm), and depending on the particular bike's geometry, it's common to see 650c wheels on very small women's road bikes (the standard road wheel size is 700c).  Women's mountain bikes are slightly easier to fit because many mountain bikes have curved top tubes in the shape of a V, making the standover height more suitable to short riders.  Hybrids and cruisers are available in the traditional "women's" step-through frames.  Women's road and mountain bikes look like their male counterparts (except for color and graphics).