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Why are there not more bicycles and accessories designed to ergonomically meet the needs of the female body? I'm not talking dresses or skirts. A range of skeletal features differentiate the female pelvis, skull, vertebra, long-bone proportion and bone angles. The female pelvis tilts naturally at a distinct angle.

For example:

  • Saddles - designed for male pelvises - create pressure points on the female pelvic floor and genitalia making cycling over extended period unendurable.

  • Handlebars that off balance the female centre of gravity - low and back - cause strain and discomfort.

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    While the saddle aspect may not be solved at least for everyone, there are plenty of saddles designed specifically for women's bodies (I've seen hints of some recent discussions, probably from Jasmijn Muller, which might be worth looking at) . Concentrating on the other aspects might make for a question that can be answered more specifically.
    – Chris H
    Jul 12, 2022 at 15:20
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    Welcome to Bicycles! In its original form your post seemed like an angry rant, and in the comments you appear to want to argue about one of the research based answers presented. Neither action is in line with our goals as a Q/A site. Please see the Tour for an overview of how this and other Stack Exchange sites work. In the meantime, I have edited your question for clarity, and to recognize that there does exist at least some cycling equipment designed specifically for women. I've also deleted the more heated comment thread.
    – Gary.Ray
    Jul 12, 2022 at 15:51
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    Your assumption that there are NONE is an opinion, not a fact. There are actually many bikes, saddles, grips, clothing and other accessories designed specifically for women, as both answers show. I have tried to gently nudge this question in a direction that is both answerable with facts, and still sensitive to what seems to be your opinion that not a single past or current attempt by any company to create women-specific equipment is satisfactory. If you find that unsuitable you are free to delete the question, or we can close it.
    – Gary.Ray
    Jul 12, 2022 at 16:25
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    That "bloke" edited your question (a normal activity on this site) because the community (not me) flagged it, & the comments attached to it as "Rude, Abusive, or Harmful". The edits were made to 1. recognize that contrary to "None" there have been numerous companies designing women specific gear, & 2. phrase the question in a way that it was likely to get factual answers, not wild opinions. Factual answers to objective questions is the goal of this site. I am trying to be as helpful and reasonable as I can, while at the same time responding as a moderator to flags by the community.
    – Gary.Ray
    Jul 12, 2022 at 19:04
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    Adding my 2 cents: respectfully, the initial tone of the question was not in keeping with the site norms. This is a pretty highly moderated site compared to the average internet fora. I think the edits have substantively improved the question, however. Please note that editing questions and answers is a common practice. We attempt to preserve the author’s meaning as much as possible.
    – Weiwen Ng
    Jul 12, 2022 at 21:23

5 Answers 5

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First, we have to acknowledge that sexism is objectively a problem in society. In athletics, a smaller proportion of women participate in competitive sports than men. Historically, women were excluded from sports entirely by men. Even now, there is less money, so less incentive to professionalize, and also a smaller market among the general public. This translates to less incentive for companies to design specifically for that market. Also, as has happened in other male-dominated fields, sexism is likely to a) reduce the rate at which women take up bicycle industry positions and b) increase the rate at which they leave the industry due to sexism.

The contention that there are literally zero women working in the bike industry and designing bikes and parts for women is not true (e.g. Terry and Tu, below). But the wider point raised by the OP is correct. The paragraph above offers an explanation of why it might have originated and persisted.

Now, if you don't build gear that women can use, they won't come! But the process of "build(ing) it" is pretty capital-intensive (e.g. frame molds, retailers holding stock in smaller sizes), so smaller companies may genuinely find it hard to do a women's-specific run of sizes even if they wanted to.


Second, should bicycle geometry vary by sex/gender? It's not 100% clear that the answer is that it should. In a previous answer, I documented that:

  • A large anthropometric study (ANSUR) in the 1950s did show some morphological differences between men and women, e.g. for the same height, women have longer legs on average than men. For reference, that study data can actually be downloaded in csv format here.
  • This spawned a wave of women's-specific design frames in, I believe, the late 2000s and early 2010s. For a given nominal frame size, these had longer top tubes than unisex (men's, really) frames. And yes, this was too little, too late. And a lot of those frames were less racy than an equivalent-level unisex (i.e. men's) frame, which may have been what average women (of the time?) wanted, but also left more performance-oriented women in the lurch. Juliana, a smaller company, offers the exact same frames as its sister company Santa Cruz, just in different colors (which tend to be more pastel due to gender roles). Currently, I believe that Liv (a division of Giant) and Canyon are two companies that I know of that maintain women's specific bike geometry.
  • The ANSUR findings have since been questioned by some newer data, which is admittedly proprietary. That is, for a given height, the average leg length for women may be equal to the average leg length for men. Specialized is one of the bigger proponents of this. I believe that there are at least some other companies that have looked at this and found similarly; Trek definitely designs their bikes unisex like Specialized.
  • Even if you take a position that the ANSUR study is correct, it may be possible to have unisex frame geometry, but you compensate for individual variation by modifying the touch points: e.g. women would get shorter stems and narrower handlebars. Naturally, you also need smaller frame sizes, and you need at least one frame size smaller than you'd have offered if you assumed that your customers were all male. The industry appears to be shifting to this approach. For sure, the major manufacturers have frame sizes suitable for people under about 5' 4" (most of whom are women) - although there are compromises in bikes that small with 700c wheels.

The OP references

Handlebars that off balance the female centre of gravity - low and back - cause strain and discomfort.

I'm not exactly sure what this means. If the OP meant that the handlebar reach (which I assume includes the stem length) is too long, then one response is that a) it is possible to change handlebar and stem length to suit, and a good shop should volunteer to exchange the items at the point of purchase, but it will depend on what they have in stock, and b) some women, like some men, do want a relatively relaxed (upright) cycling position, but some women and some men want a more racy (lower and longer) position. Shops and manufacturers do have the ability to vary how the bike fits. Also, the variety of bike fits has changed, i.e. many road manufacturers will have a performance and an endurance road model, and the fits vary between manufacturers as well.

In particular, Georgena Terry (older engineer, started making custom bikes and accessories for women in maybe the 1980s, her company is still active) and Bonnie Tu (Chair of Giant Bicycle Group, a large bike manufacturer, and founder of Liv, a women's specific division of Giant) have disagreed with the contention that unisex fits are possible or desirable. Naturally, they might be wrong on empirical grounds. However, the fact is that they have historically been right that the industry hasn't properly catered to female cyclists' needs.


Third, to sum up, it currently appears that the major manufacturers are much better at accommodating female cyclists than they were in the last decade, and that the situation is improving. It is true that the industry has fallen short in the past, and that it needs to do more to achieve parity even now. Frame sizing for the shortest riders is an area I identified; in particular, I'd like the big manufacturers to offer one small size with 650B wheels (although the range of 650B rims and tires is smaller). I think that saddles may be another area to innovate; the Specialized Mimic saddles were highly regarded by many women (and men, in this one case!), but that's only one saddle brand. By way of contrast, I've heard that Selle SMP seems more likely to work for men than for women, and they haven't seemed to put any effort into women's-specific design. Clothing to cater for a wider range of body types may be another area; Machines for Freedom is a women's specific cycling clothes retailer that does this. (I think that the current market does cater for a reasonable range of male body types, but I could be wrong.)

Some of the physiological issues you identified (e.g. that women on average may have different spinal curvature, larger knees, etc) are not ones I'm familiar with. It's possible that they are not issues, i.e. that the average woman and the average man have different spinal curvatures, knee sizes, etc given height and weight. Naturally, this is an empirical question, and someone might have evidence to the contrary.

I italicized average in the paragraph above. When I said that unisex frame design may be possible, what I mean is that given a rider height, even if women's and men's average proportions differ, that difference may be small enough to accommodate with changing the stems, handlebars, etc. Also, each individual is going to be some distance from the average. And there will be some of us who are much different from the average; for example, on most stock road frame sizes in my height, the stock stems will be 100mm or less, but I'd ride more like a 120mm stem, and my saddle will be low relative to other riders.

Similarly, you may differ from the average enough that for whatever reason, your frame isn't fitting you correctly. That could be one explanation for the issues you are reporting in comments. Generally, those can be addressed with a bike fit. Admittedly, these can be expensive, but they are well worth it for serious cyclists of all types. You can search for bike fitters by word of mouth. As with therapy, it is possible that some fitters will have a better match with you than others. You could consider asking other female cyclists for their opinions. You could consider seeking fitters who take on a diverse range of cyclists (e.g. many disciplines including touring or endurance cyclists). For example, I know one fitter in my area who does what I described, and I know one shop that I'd steer roadies and triathletes to but possibly not the more endurance-oriented folks. Be aware that bike fitting is not necessarily an exact science, and it often requires iteration to get and maintain good results - part of that is because as we age, our bodies change and our needs and wants may also change.


To elaborate a bit more on individual differences vs. group averages, consider the graph below. It's from the NLSUR study. I plotted the data in R. The x-axis is foot length. The y-axis is foot girth, which is the width at around the forefoot area (more details on the measurement procedure on the website). Red dots are male respondents, green dots are female. It's not as clear on the graph, but there's a small region of lengths where male and female respondents overlap (about 245mm-265mm, which I think are about US shoe sizes around 39-42, so the smaller of what men typically wear).

enter image description here

Women have shorter feet than men. If you fit a simple linear regression with width as the dependent variables, and length and female gender as independent variables, it would tell you that for the same length, womens' feet are about 5mm narrower than mens'. However, go back to the scatter plot and observe the vertical spread at any particular foot length. That is, some people, women and men, have narrower feet than the average. Some have wider.

The principle applies to other body parameters. Regardless of what the gender average is, some women and some men will have, for example, relatively long torsos. If women have shorter torsos on average given height, then fewer women will have long torsos, but you would still have to consider your own torso length in fitting your bike. The link in the comments to this answer may also be interesting.


For those who are familiar with linear regression and want to see the results:

Call:
lm(formula = FOOT_BRTH ~ FOOT_LNTH + Female, data = ansur)

Coefficients:
 (Intercept)     FOOT_LNTH  FemaleFemale  
     38.6140        0.2299       -5.1407  

That is, each mm of additional foot length increases the average breadth by 0.23mm. Being female decreases average breadth by 5.14mm. However, in interpreting this, do note the regions where male and female respondents' foot length do not overlap, i.e. there are very few women over 275mm, and very few men under 240mm. Worse separation than this can sometimes create problems in interpreting regressions.

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    Related to the first part of your answer, anyone with a WahooX subscription should watch the documentary 'Half the road'. It shows how badly Womens cycling has been let down and what a poor job the UCI have done in trying to create more balance. There are some signs of progress over the last ~5 years but its painfully slow
    – Andy P
    Jul 12, 2022 at 18:05
  • Would up-vote but not long enough on platform. Thanks Weiwen for comprehensive reply. I agree on all points. While bicycle design at competition level is a very serious business of fractional speed differentials, I remain convinced of need for a fundamental revisit. Rather than tweak standard model, shift focus from upper body power to lower body to use female greater proportional thigh strength, and ameliorate for weaknesses such as spinal curvature, etc. And it is under a year since the complete female anatomy model was announced!
    – padic
    Jul 12, 2022 at 18:26
  • Re upper body power: male (road) cyclists don't use much and the pros don't have much - it's wasted weight and can't contribute to propulsion. Core strength is another matter of course, and could there be a difference in the proportion of power coming from quads and glutes (without risking knees)?
    – Chris H
    Jul 12, 2022 at 18:39
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    @padic - While specifically related to men, you may want to read thestar.com/news/insight/2016/01/16/… . The difference between the 'average man' and a man is probably greater than the difference between an average man and an average woman, Bicycles have evolved to be nearly infinitely adjustable, to the point that 'woman's bikes' are painted pink. (Saddles are excluded, but there is a huge range of woman's specific saddles.).
    – mattnz
    Jul 12, 2022 at 20:54
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    @mattnz: this is the insight I was going to post. The difference within each group dwarfs the differences between the hypothetical averages. Jul 13, 2022 at 3:19
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During the 2000's and early 2010's it was common to see a range of mens/womens specific products. However some of the major brands did the research and discovered that for most parts of the bicycle there was no difference between the requirements for a mens/womens bicycle.

The main difference has been found to be the saddle, and there are plenty of womens specific saddles available to buy. In brands that do still differentiate between mens/womens bicycles the saddle is one of the components that will be different.

Specialized have a webpage detailing the findings of their research: https://www.specialized.com/us/en/beyond-gender

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    And of course stack and reach can be adjusted with stem changes, and shoulder width can be dealt with by changing the handlebars. Then different sub-styles of (road, for example) bike have different effective toptube lengths, mainly for different use cases but also available to suit different riders' proportions.
    – Chris H
    Jul 12, 2022 at 15:07
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    I suspect though that there's a "default male" assumption in the components fitted as sold, so women further from the proportions assumed by the designers will end up having to spend more on changing parts to get a good fit
    – Chris H
    Jul 12, 2022 at 15:10
  • all fair comments. my question still is though shouldn't there be a project to design the ideal bike just for women. I imagine were the female centre of gravity optimised the result would look actually very different to what is too readily accepted as a unisex design.
    – padic
    Jul 12, 2022 at 15:42
  • @padic when you say "ideal" do you have in mind a particular use case? Road racing (with UCI restrictions), MTB, utility cycling, and touring all tend to put riders in different postures,with different ergonomics
    – Chris H
    Jul 12, 2022 at 16:02
  • As it happens I did a few long cycles across country over range of surfaces in the last few days and realise what are only minor discomforts on a shorter trips become debilitating over longer cycles. I have changed saddles adjusted stem heights etc but am now convinced that there's a basic design flaw at issue viz for women and bikes. -
    – padic
    Jul 12, 2022 at 16:13
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This is a complicated question. There are lots of saddles designed for women, or saddles designed for different sit-bone widths. On road bikes, at least, some brake levers have adjustable reach for smaller hands. And there are some bikes (and at least one mass-production bike brand, Liv) specifically for women.

But the conventional wisdom that women have different long-bone proportions derives from a U.S. Army anthropometric study in the 1960s that has since been found to be inaccurate.

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  • Females are smaller with shorter legs, narrower rib cages, wider hips, smaller shoulders. Female pelvises inclines differently and female spinal curvature is greater. Female elbows and knees are bigger. A few differences ignored by designers which add up to lousy bikes from a woman's pov.
    – padic
    Jul 12, 2022 at 14:18
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The only body part which is really women specific is easily addressed with a specific saddle.

All the rest is just usual bike fit stuff: Stack, reach, handlebar width, crankarm length ...

There are some issues for smaller, lighter people (not just women):

  1. Brake levers and shifters require big hands and some force to operate properly. This is mostly a mechanical problem but has gotten better with hydraulic brakes and electronic shifting.
  2. Related: The diameter of handlebar tubes and grips can be too big for small hands.
  3. Bike components are made for >85kg rider weight which results in a normal road bike weighing ~7kg. For a 50kg rider that’s 14% of your body weight which you have to pedal up inclines or lift up stairs. For a 90kg rider it’s only 7.7% of body weight. It would make sense to have lighter, more fragile components for lighter riders.
  4. Most bikes are made for 622mm diameter wheels. It gets hard to make frames for people smaller than ~1.6m without implementing some compromises (and it does look kind of silly)
  5. Drag affects smaller people more because their cross sectional area (and that of their bikes) is bigger compared to their volume and power output.
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    @ChrisH: Does a 50kg rider need 31.8mm handlebar diameter, 30mm crankset spindles, saddlerails which can support a 100kg person, a chain which survives 2kW sprints, 160mm disc brake rotors and so on? I mean … sure, there is a limit to how thin you can make walls and how narrow you can make tubes, but I really thing most bikes and ”standards” in the bike world are more designed for 100kg cyclists (and pro level power output) than 50kg cyclists. It affects everything from the diameter of quick release skewers to the strength of the freewheel mechanism.
    – Michael
    Jul 12, 2022 at 20:00
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    No one needs 31.8mm handlebar diameter - that's an interface standard, not an ergonomic one. But putting that aside, to get half the stiffness in a tube, you save very little material indeed - you can reduce the OD a little while keeping the wall thickness the same, but you often can't reduce the wall thickness as the resistance to incidental impacts is reduced.
    – Chris H
    Jul 12, 2022 at 20:17
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    160mm rotors are small, but you can get 140mm (and up to 220mm, so they can scale with rider mass to some extent - if frames and forks scaled to support the changing rotor size or us bigger people could use spacers)
    – Chris H
    Jul 12, 2022 at 20:18
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    It does seem daft though that a 20" wheel kids bike can take my weight, standing on the pedals to ride
    – Chris H
    Jul 12, 2022 at 20:21
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    "There are some issues for smaller, lighter people" I wonder if its a bell-curve, where the smaller or lighter are on one end, larger and/or heavier are on the other end. Example I cannot find many frames in 63cm or larger, and bike shops have to special-order such sizes.
    – Criggie
    Jul 12, 2022 at 21:53
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Some differences disappeared together with now largely obsolete dress codes and behavioral rules.

  • I still remember the times in my home village in Lithuania when any a guy to ride a low-step / step-through frame would be seen just as wearing female clothing, with the comparable attitudes and consequences.
  • When pushing a bicycle, a guy was expected to walk left side of it, and a girl right side of it. But there is a (often dirty) chain on the right side, so a "truly female" bicycle would either have it on the left or much better covered.

There were "female bicycles", and they were not uncommon, and these differences were respected. And this is when there was often just only one frame size for everyone, witch smaller boys riding diamond frames on one side with leg through the gap below the top tube.

With old differences obsolete, new differences need to be discovered and scientifically proven. It may not be so trivial to do, and many differences would be more for the height of the rider instead. Also, many things can be adjusted.

Quick web search shows that cycling does not look unpopular between women and seems growing. The market should push for specific parts if makes sense.

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    I've seen similar attitudes here in the UK. But the old "women's" designs were more about clothing and expectations - they were shopping bikes. To some extent this is true in the hybrid/city/utility market now, though lowered top-tubes may have more to do with tradition than skirts these days. Women who rode fast or far tended to ride "men's" bikes
    – Chris H
    Jul 18, 2022 at 10:00

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