Sunday, October 19, 2008

Bike Fit, How Does It Work?

Springtime Seven
Preparing my roadbike for the first skinny tire ride of Spring, I realised it's now been over a year since I've had it. And, looking at the somewhat unsightly spacer poking out above the stem I realised something else: My road position hasn't changed over that time. That bit of steerer was left uncut in case the handlebars turned out to be too low for comfort, which did not happen. The spacer below the stem has remained in place as well. Considering that prior to a year ago my position was in constant flux, it's nice to finally feel settled in.



Alas, this has not given me any great insights into the topic of bike fit.I have seen huge variations in the positions of people I ride with, each of them apparently suiting the rider just fine.I have also been exposed to a number of fit philosophies - each yielding a different conclusion about the size and setup of the bike I ought to be riding.Seasoned cyclists often advise new riders to "have an expert fitting." But depending on which philosophy the fitter subscribes to, results will vary.



Since my bike is a Seven and Seven Cycles are known for their fit methodology, I am occasionally asked to describe the fit process I went through. While I don't think my experience was typical, this seems like a good occasion to share it, so here goes:



When I first tried a Seven demo bike two summers ago, they set it up to match the position of my own bicycle. At the time, I was riding a bike with a long top tube, short stem, handlebars slightly above saddle height, and saddle pushed back to slacken an already relaxed seat tube even further. Setting up the demo bike to match mine was contrary to what I had expected going into the test ride. But Seven's Rob Vandermark suggested I start from a point of familiarity. Set up in this manner, the Seven felt good, and with the fit already familiar I could focus on its ride quality and speed. But this was a long term demo, and when I began taking part in fast group rides that summer I found myself squirming around: bending my elbows dramatically and scooting forward in the saddle. When I communicated this to Rob, he suggested some small changes, including moving the saddle forward and lowering the bars. When this adjustment was made, it felt like a step in the right direction. Eventually I was riding the bike with a straight seatpost and the handlebars placed as low as the frame would allow. It still wasn't quite right, as the frame was simply too large. But it felt better than my previous position.



Later that Fall, I built up a small vintage racing frame with modern components, based on the ideas of fit I picked up from the summer's experience. This bike had a short top tube and long stem, and handlebars just below saddle height. Though I sensedit could still use some tweaking, overallI wasnowvery pleased with my position. When I decided to buy a Seven for the coming spring, I came in with this bike and was measured again, as well as observed and asked questions while I rode on a trainer. The kind of things that were examined and discussed were: my cadence, where I keep my hands on the bars, how much time I spend out of the saddle, my back and shoulder position, the position of my feet on the pedals,and lots of other little things that I no doubt missed. Moreover, this was also the time I became involved with the Ride Studio Cafe cycling club (a Seven Cycles dealer) - taking part in their group rides and loitering in the shop. So my formal fit experience was no doubt supplemented by their getting to know me and my riding style.There is talk of a famous 50 page questionnaire that Seven customers fill out, but I have never seen such a document; I assume it was filled out on my behalf during and after the fitting session. I did sign off on a build form in the end, and hoped for the best.



When I got the new bike, it fit differently than anything I had ridden previously, but I was left with no doubt it was the "right" fit for me. There was a sense of everything falling into place. My hands knew where the hoods were and plopped right down; my legs felt integrated with the cranks and pedals. I didn't question any aspect of the positioning. Any other roadbike I've ridden since, I try to adjust to the same specs. Depending on a bike's size and geometry, it doesn't always work - but the closer I can get it, the better it feels to ride.



And by better, I don't mean abstract notions of "position X will make me faster/ more comfortable than position Y." Neither do I have a template in mind of what constitutes proper road fit or of what looks correct. Rather, I mean physically better - proven through personal experience to feel both more comfortable, more efficient and less fatiguing. I notice, for instance, that contrary to one popular narrative, my back hurtslesswith the handlebars set a bit lower. And contrary to another, my legs feel better with the saddle at a steeper, rather than a slacker angle over the bottom bracket. I don't presume that the same holds true for every rider and for every style of riding, but I can't ignore evidence of what works for me.No doubt in the future, my position on the bike will continue to evolve. At what point and in which direction I don't know yet. But for now it might be safe to cut down the extra bit of steerer - affectionately referred to as the "sternum puncher" by some of my riding friends.



Funny thing: I know about half a dozen female roadcyclists who are almost identical to me in size and who all do similar types of riding. When we try each other's bikes, hilarity ensues: The fit is all wrong. Yet we each find our own positions comfortable. And all of us have had expert fittings.



As these things go, I sometimes get bike fit advice from strangers when I am out and about. It is split pretty much evenly between (a)"Your setup is way too aggressive," (b)"Your setup is not aggressive enough," and (c)"That bike is set up just right!" I have a feeling that no matter what my bike looked like, this distribution would remain about the same.

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