Three Points in Space
Most great ideas in life are accompanied by an unforeseen consequence of equal or greater magnitude. For instance, no one predicted that the Industrial Revolution would pollute our air and set off climate change on a global scale. Similarly, no one realized that when placing unfathomable computing power in the palm of our hands in the form of smart phones, it would gridlock traffic as people sit idle at green lights while updating their Facebook statuses. But most of all, no one anticipated that the invention of the Internet would reveal an entire population of people who can judge the quality of a rider’s position simply by looking at a photograph of the bicycle itself. That’s quite a Carnacian talent, one that might have saved the great Eddy Merckx quite a bit of time and hassle.
Legions of people have tried their hand at methodizing bike fitting for the obvious reason that it is theoretically possible and sounds nice and tidy. The problem is that we don’t understand the alchemy of biomechanics, aerodynamics, and physiology that determines the rider’s optimal position. As it stands, bike fitting is more art than it is science where experimentation informed by performance is the only way to get things perfect.
Eddy Merckx was famous for being relentlessly obsessive about his position. A Sunday in Hell and La Course en Tete both show him at work setting up his bikes; measuring the angle of his saddle with a spirit level and basing the height of his saddle and bars from the top tube instead of the more customary measure from the bottom bracket.
In contrast, Sean Kelly was known for giving his frame builders one measurement only: the height from the center of the front axle to the center of his handlebar stem; he felt that so long as he could get his bars at the right height, he could work out all the other dimensions as well. I used this method for years, until I realized that changing the bottom bracket height changes this measurement directly; every centimeter in bottom bracket height dropped increases the effective height of the bars by the same amount.
The fact is, our position is determined by the three points in space by which we are connected to our machine: the bars, the saddle, and the pedals. The frame, stem, cranks, and seatpost are just a means of holding them at the precise coordinates we determine for them. Replicating a position precisely from bike to bike is a challenge that I have yet to meet; I have gotten close, but I have never gotten it perfect.
The critical distances are the saddle height, bar drop, the reach to the handlebars, and the distance the saddle sits behind the bottom bracket (setback). To get my position as close as possible between machines, I standardize all my contact points; I use the same saddle, bars, and crank length on all my bikes which lets me eliminate those variables from the equation. Standardizing on a saddle, for instance, allows me to measure the saddle height from the bottom bracket to the center of the saddle rail which is less error-prone than measuring to the top of the saddle. Then I measure saddle setback using a plumb line and drawing marks on the floor to indicated where the bottom bracket sits and where the tip of the saddle is (the distance between them is the setback.) Then I measure the vertical height of the saddle to the ground and measure the height of the handlebars to the ground; the difference between these two numbers is the bar drop irrespective of bottom bracket height. (If you know the difference in BB height you can also add/subtract that difference from the axle-bar measurement.) Finally, I measure the distance from the tip of the saddle to the center of the bars.
In order to replicate this on another frame, I start with the saddle height, then setback, iterating between the two as you zero in on the correct measurement (sliding the saddle fore and aft will affect its height slightly; raising and lowering the saddle will affect the setback). Then I set the bar height, and then reach, also iterating on these two as the rise of the stem will mean you lose bar drop as you increase or decrease the length of the stem.
It all takes time, and unless you are using identical frames, you’ll never get it completely right. But you can get close. Also, you can consider the approach of caring whether your position is the same on all your bikes or not. I have friends for whom this works and who even enjoy having different positions on different bikes. They claim it lets them appreciate the different personalities of their various bikes. This approach is obviously completely incompatible with my personality type but does, on the surface of it, appear to be quite a lot easier than my approach.
Excellent piece! With all the various geometries of frames these days and an adherence to N+1 means getting things very close is about the best you can hope for. I use same saddle and bars on three of my five road machines. Crank length is the same too. Even with things close to within 5mm or so (mostly on bar drop) the various personalities of the different machines is still apparent. With new style stems, getting the each, bar height is much easier than in the day of quill stems, that’s for sure.
I still check the mmeasurements every once in a while just to make sure they haven’t changed . . . .
I’ve come to my position by years of trial and error. I can ride for hours with no pain in my back and knees and only after 3 to 4 hours some stiffness in my neck but that’s just ageing. In a couple of weeks time I’ll undergo a full Retul bike fit and all that entails with led markers/ sensors and The Zin. The fit was a gift, I wouldn’t have paid to change something I don’t think is broken.
I don’t think my position is bad but I’m now very interested to find out if it could be better and why the technology says that. This fit will be only for the #1 as the fixed/ CX/ track and MTB are different beasts although the track and fixed are likely to be pretty close using similar measuring methods to Frank’s, perhaps slightly less OCD? Maybe not. I’m also part way through BC’s Head Physiotherapist Phil Burt’s Bike Fit book. It’s an interesting read and so far is backing up my own bike fit. It’s worth getting just to check out latest thinking and BC’s work on the subject.
Here is a good tip for measuring saddle setback.
push back wheel so it sits flush against a straight wall.
measure level from wall to your chosen reference point on saddle, I go for the tip
measure level from wall to centre of bottom bracket
take awat the difference, voila your saddle setback and not a marker pen or annoying plumb line in sight.
So easy and accurate, just make sure the wall is straight if using different walls.
Ah fitters and their gadgets. I have had three fits over the years. They have varied by 2 cm in saddle height and 1.5 cm in fore/aft; Never mind the guy who convinced me my pedals were too close together and stuck me on the oddest one off pedal system ever seen.
Needless to say I am now convinced that Merckx was correct here as in so much else; get a torque wrench, a tapemeasure,a level and a notebook and do the work yourself!
Methodized bike fitting has been defined. It’s Cycling Analysis. It’s Cyclologic. Cyclologic.com for the curious. We have done what you seem to promote as unattained (alchemy?? huh?). However, you are correct in understanding that it is both art and science and it probably always will be. Yet, even with the accuracy of analytical tools, to find a proper fit requires a Cycling Analyst (bike fitter) with an intuitive understanding of biomechanics, and cyclists’ individual anomalies is paramount. Considering the outrageous amount of time a cyclists spend in a relatively static position on the bike, millimeters matter in the long run. It is millimeters of error that cause pain and saddle sores and discomfort. It is centimeters of error that cause malaise, back pain, and rapid burnout. With tools like pressure mapping and high speed resistance based motion capture, these asymmetries of the human body can be identified compensated for through correct frame size and accurate fit. But it would be foolhardy to think that the simple title of “bike fitter” alone is licsense enough to solve these kinds of problems just the the term “bike mechanic” does not qualify all who work on bikes to touch Campagnolo, ESP, Di2 or carbon. Training and – again – and inherent passion to understand the complex nature of cycling biomechanics is requisite. As spammy as it is to say it, Cyclologic has attained this and we see Cyclists of all levels travel to us because they know our abilities are Hors Categorie du Alchemy.
I was blessed with a freshly printed copy of LeMan’s book as a pedalwan and set my position up using his paraphrased genius. Since then (save for a tendancy to move my handlebars lower over the past decade) my position has remained steadfast enough for me to set up a new bike sans measuring tape just by riding it a bit and making the occasional adjustment. They all end up with identical set ups.
Its the one area of my life where a pathological sense of anal-retentiveness has not directed my behavior like, eh-hem, some of the others here.
@pneaumme Was going to bring up high-tech fitting methodologies to get a feel for what others thought. I’ve always done iterative ways of dialing in my fit, i.e. drop the handlebars by a spacer, go ride. Feel OK? Drop another spacer. Too low? Put it back on. Etc etc etc. It seems to work reasonably well, but I’m a biologist not a physiologist, so it might be nice to bring some biomechanics and actual quantification to bear on the problem. It would be, as they say, sexie.
Just bought a new seat clamp after raising the saddle a couple of mm’s and going ‘two turns passed stripped, then back it of half a turn’ to tighten the clamp. Feel the need to go a bit higher again. Tip – if you’re going to Eddy Merckx about your position, get a torque wrench!
Here’s another headwreck thought when setting postitions on your muliple steeds, or with multiple shoes – cleat position on the shoe.
Some folks are sensitive to mm changes, some are not. I for one, am not.
After buying a new bike and setting it to match the old one I rode it for a a few months. Position fine. I then decided to drop the 5mm spacer out from under the stem that wasn’t there on the old one… I’ve been riding it like that for many many months. To me the position feels the same….
@Simmo
That is good! Do you use a long level to get the horizontal? And so long as the wall isn’t too wonkey or as you say you use the same one, everyone is happy.
The plumb line is a it of a hassle. I’ve designed a contraption in my head that would work as a gig but it’s never going to be built.
@beatarmy
Totally agree, just tweak until you’re happy and ten tweak some more until you’re not. Then go back. When you go mo’fasta the posish is right.
Amazes me the eye for fit a guy like Guimmard had – all his riders looked just perfect. LeMond, Hinault, and Fignon being the best of his disciples.
Eddy Merckx though was possibly obsessive about it because of back pain after his track crash in 1969, and, furthermore, is reported to have adjusted key dimensions during rides in order to relieve back pain, rather than in an effort to get the one perfect setting. Chris Sidwells in ‘A Race for Madmen’ quotes him as follows: ‘I started taking an allen key with me on every ride. At first I thought my pain might be due to a slightly incorrect position on my bike, so I changed the saddle height slightly, but the pain came back. I experimented some more and every time I changed the saddle, or the height or angle of the handlebars, the pain eased for a while’.
Like @Ccos I seem to have come to fitting early and easily. If memory serves when I started riding long races at 40kph position became something that got sorted pretty quickly. Now just getting on any bike and muscle memory can get me dialed in quickly.
The only thing that makes me think that I have it easy is that I am average height and do not have any kinks in back, legs, knees or feet. For those that do I can not imagine the hassle in getting set up. My adjustments go to the millimeter for cleats and within +\- 5mm for saddle height. Stem and set back are more forgiving and the change is enjoyable.
I have found that pedal float helps me find the sweet spot for cleats, meaning that on the new Looks if I get close then listen to my feet then I will be able to set them gradually to where my foot goes most. Of course Speed Play would negate all that.
On the saddle height spinning over 120 will make you bounce weather you are a little over or a little under your optimal height. Once adjusted, sometimes as little as 2-3 mm, up or down to find the sweet spot the bounce goes… assuming one has a good stroke! This works a treat on fixed and then transfer that height to the road bike and raise it a tad for more power.
@Owen
And that’s exactly what the FIST fitting protocol is all about. You get on a fit bike – the fancy ones are even motorized and wireless – and pedal away. Fitter changes something until it’s too much, than backs off until it’s too little. Again and again, but a FIST fit will take an hour or three rather than several days – and you can “put your finger on it” much more easily if you can swap between two setups back and forth within seconds.
Completely agree with this. So much so that I’m tempted to make my next road machine one size down in frame size, while matching these three points equally to my current No 1 steed. This means building it myself, with proper crank length, bar width, stem etc…. Looking forward to the experience. (recently replaced all my componentry myself, so feeling much better about taking on such a task)
Yet despite it all it did not always work so precisely for The Prophet. I like the bit in a Sunday in Hell where he gets a spanner from another team car and gives the saddle a bit of a whack before tightening and setting off again. The benefits of a newspaper strike impromptu stop if I remember correctly.
@frank
Nice technique there! I have a contraption for measuring plumb line – a long (4′ I think) level with a base on one end. Set up next to the BB and measure back to the saddle tip. It’s also good for saddle/bar drop and saddle level too. I got a friend to make it up for me. So long as you work on the same area/floor when measuring different bikes, it’s all good.
@Teocalli
I was thinking of the exact same scene. He borrowed the spanner from Brooklyn no less IIRC.
@wiscot I keep thinking a nice big drywall square would be just the thing for accurate setback measurement.
@Nate
I use that, and a 48″ level lined with the center axis of the crank (level at the crank, drywall square to saddle). If the frame geometry varies between bikes, this way of measuring always puts my knee is the same position over my foot.
@frank – The lead pic could easily show up in an AOP article:-
Q: How many men does it take to find Eddy’s saddle height?
Couple of things here. Part of the reason the Prophet was always fiddling with his position was as a result of his 1969 crash at the Blois velodrome where he fractured a vertebra and twisted his pelvis. He admitted that subsequently he often rode in pain and was never the same rider again. One can only imagine his career had he been fully fit!
His bike is getting the full measurement/adjustment protocol because His sideburns have already been treated to the same meticulous measuring and positioning. No stupid-looking beard here, just hirsuite awesomeness!
Yup, I’m in the tribe of not minding, and even enjoying, a slightly different set-up/position on all of my different bicycles. As your friend points out, it brings out different personalities. But, the bb-saddle height and reach is pretty darn close on all of my bikes, even my do-it-all commuter.
When I first got into road cycling I laughed at people discussing cms or even mms of difference. Over a decade in the saddle, I now know how easily you can tell your bike is off if a pillar has slipped or a buddy has played a joke and moved something.
And the distraction of phones. GREAT story for ya – down the block from where I live a college kid was robbed at…hammer-point. I’m absolutely positive they were texting and also wearing ear buds, so fucking distracted they let a strange dude wielding a hammer get that close to them without even looking up. I’m continually amazed at how distracted and addicted people are by their phones. Sure I’m not the only one, but I’ve seen two people out at a restaurant hardly interact with one another the entire meal, just head down, playing away. Bonkers.
@Ron When I first got into road cycling I laughed at people discussing cms or even mms of difference. Over a decade in the saddle, I now know how easily you can tell your bike is off if a pillar has slipped or a buddy has played a joke and moved something.
Whoa! We’ve had discussions here about the massive inappropriateness of just sitting on another guy’s bike. Fucking around with moving things is beyond the pale. That is not funny, not now, not ever. That would be the act of an soon-to-be ex-buddy.
@wiscot
Hell, there’s not a single hair on his head that’s out of place!
So long as I am comfortable on my bikes I don’t bother much with the minutiae of fitting. In addition, I doubt that Frank’s methodology would be completely accurate: different frame geometry from bike to bike. A couple of degrees can make a noticeable difference based on my observations, but then again I am no expert.
@wiscot
This. That was apparently a really gruesome crash while in a motor-paced race. The derny driver died in the accident, Merckx had head trauma and the infamous back injury.*
Thanks to some archived articles on this site, I’ve been fiddling with my saddle and bar positions lately. I’m not exactly sure why, since I’ve been comfortable and low for years. I actually had some (self proclaimed?) bike fit guru say I would generate more power if I wasn’t so low. I found that absurd, since I’m barely hitting the Rules compliant 4cm drop. Today’s suffer-fest proved that experimentation can be good or not so good. Back pain all day, time to re-evaluate my changes.
*as cited in Eddy Merckx: The Greatest Cyclist of the 20th Century. Why is this not listed as required reading here?
@pneaumme
does your fitting program study a rider over the course of serious riding for half a season or more? If not, you are telling yourself convenient stories about how comprehensively you understand the system.
As a scientist and mathematician who flirted with physics, I agree the idea of defining this stuff comprehensively is awfully tempting.
@Ccos
I have bought a new copy recently which I love. That dude rules.
he espouses the virtues of riding the smallest frame possible and I’ve noticed since that his stem was always slammed. Stud.
@Puffy
I envy you but also am sad you don’t get to experience the satisfaction of getting it right.
@Len
Yeah. We all have excuses for our obsession. Although I know this is true of Merckx to some degree. He’d also have his mech keep bars wrapped with different length stems to swap during races. But his obsession still points to one thing: a compulsive nature.
And who knows, maybe if he’d ridden a 20cm drop like I do his problems would have resolved themselves.
@Rob
Let me summarize: for those less awesome than @Rob, too fucking bad. He’s awesome. You’re not.
Everyone without a magnificent stroke can tune out. Everyone else, train on a fixie and go up a tad for Maximum Awesome.
@frank
True to my dual Dutch/Canadian nature, I fashioned a gig using a hockey stick, level, measuring tape, and, of course–duct tape. Cheap and works great, eh?
@wiscot
That’s all very well, but what the f#*k has happened to the page with ‘The Rules’? When I click on it now I just get a blank page with a message ‘sorry, no posts matched your criteria’. I’m about to make public a blog on a ride a group of us are doing across Oz from West to East in which stict adherence to ‘The Rules’ is part of the discipline, but the link to it leads to sfa.
Help!
Spikey
@frank Yes. As well your tone of professional arrogance is Very Hors. We appreciate this.
We work continually with our clients throughout the season, pre & post. Our clients range from category cyclists, olympians, juniors. The list is of weight, I assure you.
Thank you for your excellence in trolling.
What I love about the lead picture is that it takes five people to get the Prophet’s bike set up – I’m assuming Mr Trenchcoat in the back is handling the spare bike. This is an attention to detail that Sky can only look at in wonder and envy.
@pneaumme You’re done now — right ?? I for one need to figure positioning out on my own; change saddles on my decision; compare bars and drops as I want; go as far with stem length and angle as need be; alter crank arm length to feel for myself. And purposefully build different frame sizes to find it all over again. Methodized is always boring and not very meaningful.
I was a better climber on 172.5mm cranks but then became a better killer at 177.5mm. And finally to dispel my “unknowns” went to 175mm.
@wiscot ” I’m assuming Mr Trenchcoat in the back is handling the spare bike.”
Or stealing shit while no ones looking. It’s like the crowd photos where the one dude not smiling is the one who’s gonna shoot the president or something. How come he’s squandering his opportunity to stare at the Prophet’s bike with rapt attention like everyone else?
My ‘technique’ for this is to have a few bikes with different geometries and frame sizes, and have the utopian ideal of getting them all set up the same. I then use each ride as a sort of pairwise comparison, comparing the position of the current bike with the last one I rode. If I dislike something about the setup of the current bike, I change it. If I think something about the setup of the current bike is better than the previous one, then I go out on the previous one again for a quick spin and then maybe change something about that.
Done properly, this could keep me occupied with bike setup for at least one lifetime. But in reality, after several iterations, they’re all pretty close, and I don’t think I’m that sensitive to minor discrepancies anyway.
Being an engineer by education I have a fundamental desire to build a jig, but this would a) assume that one bike has an ideal setup, which is probably untrue, and b) deprive me of the dissatisfaction – rectification – satisfaction – and repeat cycle that seems dissatisfying but in reality is part of the fun.
@freddy
@freddy Nice one Red
@Geraint
Close but not quite exact is a good thing – it always gives you an excuse to go to wherever you keep your bikes and fiddle with them. Measure, measure, compare, adjust, ad infinitum. It is indeed the basis of the lifelong pursuit of the virtually unattainable goal of perfection.
@pneaumme
In defense of Frank, you opened a Pandora’s box of nerdness with that first post. I’m just relieved my comment on anal retentiveness flew under the radar.
@Ccos
Don’t be so sure. Everything, and every article, that’s recorded on this site is available for resuscitation. As can be evidenced by the posts made in the wee hours.
@Bespoke Heh-heh! True my brother, especially when there is a target audience.
I got into road cycling on a fixed gear about 1.5 yrs ago. Fitment was “seems good enough [buys online]”. Then, I made it worse (better?) by trying to emulate bikes I saw on pedalroom, none of which was for a rider who looked anything like me (about 60 lbs overweight). Stem slammed, narrow bars, etc. But I got on , and rode, and it all sorta worked out.
When I bought a road bike with an actual proper fitting included, it just felt weird. Too comfortable. And then after putting in miles on the road bike, I felt real wrong on the track bike with 38cm bars when I rode it to work the next day.
Nowadays I like taking both out for their different personalites. Is either fit “wrong?”
I think they’re suited to their purpose. It’s nice to feel comfy for rides over 50k. Bombing traffic in a riding position like a monkey fucking a football works for the “tarck” bike.
Horses for courses camp, here.
@strathlubnaig
@strathlubnaig +1
@freddy, Now do your curtsy!
@Frank, not quoting post #32 because, well I’m just not, it boarders on all wrong for the right reasons that I don’t understand but may have to do with late night shenanagans in NJ, now years ago! Cheers.
@Nate
Best example of being Casually Deliberate EVER.
@Ccos
Because his name is “Ugo de Rosa” and he will be setting up Merckx’s own bike building business for him a few years later.