Olympian sized problems for everyday cyclists...

Having just watched GCN's excellent video featuring Olympian and ex-pro Emma Pooley's new custom Bond https://www.youtube.com/watch?v=o3VThDiZ-HU, I got to thinking about how so many riders experience similar issues to those that she's experienced, and about how the industry has, and still is, failing riders who fall outside the fleshy part of the size/proportion bell-curve.

I admit things are changing for the better, but it's a slow process led only by the more forward-thinking companies who have only relatively recently become aware of the massive increase in female cyclists, leading to a higher demand for smaller sized bikes and altered geometries. Emma has the benefit of experience and sponsorship to fall back on (not to mention a PhD in engineering), however, most riders do not have this kind of knowledge or support, and the industry needs to step up and take the slack.

Most of the modern understanding of cycle-related physiology and bio-mechanics has been led by bikefitters, whether this has been intentional or not. The issues uncovered by fitters in the last decade have provided the principles upon which those forward-thinking bike and component manufacturers could base their decisions; decisions on design, component choice and decisions on frame geometry. Of all the issues mentioned by Ms Pooley, some have already been addressed, however, there are others which continue to be problematic.

Why am I so passionate about these behind-the-scenes issues? Because they directly impact my job as a fitter in the positioning and optimisation of a rider on their chosen bike. Here are some well-known examples which relate specifically to positional and functional issues I regularly come across during bike fits.

 

Crank length

On stock bikes crank length is often too long, particularly on the smallest sizes. Typically, the smallest stock bikes have always come with 170mm cranks, a function both of historic belief and of manufacturers wanting to maintain as few product SKU's as possible, to reduce stock holding costs. Campagnolo, one of the Big Three component manufacturers still do not offer a crank shorter than 170mm. Ask any bikefitter what they think of this and they'll just shake their head, this is how incomprehensible it is. An overly long crank will almost certainly compromise the performance of the rider stuck with it, forcing that rider to turn an excessively large circle when pedalling, leading to either impingement at top-dead-centre, or an excessive leg extension. The fact that the smallest bikes aren't fitted with short enough cranks is a kick in the teeth for those riders who require those frame sizes, and is an ongoing issue on most manufacturers' production bikes. It affects smaller riders the most but can also affect average sized riders with proportionally short legs.

 

Seat tube angles

Once again we are faced with an historical legacy, a legacy which was based on flawed fit principles as well as a desire, on smaller frames, to find a solution to excessive toe overlap. That legacy is slowly disappearing, though in my opinion not fast enough.

In the past, most small frames had quite steep seat tube angles, and the biggest frames almost always had relatively slack seat angles. The reasons for this tendency, as mentioned above, were both belief driven, and design/function driven. When Cervelo came out with their range of bikes, complete with the exact same seat tube angle on all sizes, the industry was surprised and very confused. Then Guru followed suit as did Canyon. However, it's now apparent that the manufacturers who've moved to a single seat tube angle are actually on to something. And though this outlook is a debatable one, interestingly Canyons, with their 73.5 degree seat angle, produce far fewer seat tube angle issues for me than other brands I see coming through my fit studio. But we still exist in an industry which largely believes that small bikes require steep seat tube angles.

 

Top tube lengths/frame reach

With the gradual industry acceptance of stack & reach measurements, the issues related to top tube length assumptions and preconceptions are thankfully slowly beginning to fade. However, these issues still exist in a large number of bikes on sale at this poiny in time. Some manufactures still today, produce small bikes which are the same length, if not longer, than the size above (I can give examples to anyone interested). To compound this problem, ill-informed shop staff often recommend smaller bikes to customers in order to solve a reach problem, even though these smaller bikes are effectively not any shorter, and so don't actually solve the problem. The short term solution is for riders to avoid these bikes, the long term solution is for manufacturers to produce small bikes which are consistent in size decrease. But it's a slow process, once again led only by a few forward-thinking companies, dragging the rest of the industry slowly behind on a “me too” basis.

 

Fork rake on frames suffering with toe overlap

Toe overlap is the bane of some riders lives. And although it's an issue which can't always be eliminated, it should always be minimised. And manufacturers should be active in the solving of this problem. Small frames and frames designed for the use of mudguards are usually the ones to suffer from toe overlap. Historically manufacturers used steep seat tube angles to overcome the problem on smaller bikes, but as mentioned above, this led to overly long frames. The only real solution here is for manufactures to supply these bikes with forks which have more rake built in. It's a no-brainer. More rake with the associated slacker head tube angle, combined with a shorter crank, will all go a long way towards eliminating or at least minimising toe overlap.

At this point in time it looks like things are going in the right direction, thankfully. But riders will, for the foreseeable future, continue to arrive at bike fit studios with bikes and equipment ill-suited to their physiology. It's the effect of historical norms, flawed principles, disinterest and bad advice.

Fitters can and should help solve or avoid these issues, either prior to purchase or post-purchase, however, what is necessary is a more direct feedback loop of information between fitters and manufacturers to increase the speed of this process.

It's a shame that it takes someone with the stature of Emma Pooley ('scuse the pun) to bring to light issues that so many other riders experience, but also a shame that Ms Pooley has, in her years as a pro, had to deal with the industry's inherent lack of awareness and concern for the needs of smaller riders. Emma has had to learn and adapt to sort out her own issues, a luxury most average to tall riders take for granted. Let's hope these things change quickly.

 

www.form-bikefit.co.uk

 

 

Ronan Descy2 Comments