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Road fit protocol
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i need your help. pardon the long intro...

FIST is getting into road bike fitting? why? aren't there enough good road fit protcols out there? the answer is, yes, probably there are enough good road fit protocols out there. the reason we're getting into road fitting is as follows:

for at least the first two years of its existence, the FIST system was, "here's your fit coordinates, now go home." it became obvious something was missing, namely, now that i know my fit coordinates, what bike in what size with what aerobars will fit these coordinates?

so, part-2 came along, matching fit coordinates to bikes for sale on showroom floors. of course, as you know, this required the development of a set of metrics that would match all bikes to all other bikes, apples-to-apples. stack and reach. lo, i was surprised when engineers and product managers said, "you know, this stack and reach thing works pretty well for road bikes too."

i'm a little slow on the uptake - it took a couple of years - but it finally dawned on me that there's a pawcity of fit systems in road race that have an analogous part-2 to their protocols. in other words, the output of a lot of road bike systems is, "here are your fit coordinates, now go home."

or, "here are our fit coordinates, here's the custom geometry that we'll build for you." or, "here are your fit coordinates, here's the bikes that our brand sells that will work for you."

and all that is fine. except, no retailer, other than he who runs a concept store, has one brand only he's selling. there is no time to put a customer through three separate, parochial, fit processes to find out what, among all the bikes a retailer sells, will fit his customer.

what was needed is - like the FIST system - one ecumenical fit system for determining fit coordinates, AND to match that up to ALL the bikes on a retailers floor that may fit a customer, ALONG WITH the custom geometry, if a custom bike is in that customer's future.

furthermore, i thought it an elegant cost and space solution to offer a protocol that would require one fit bike (not two) and one fit studio (not two).

with all that as a backdrop:

what i'm looking for now is a protocol for road that will not be jarring to you. one that will use generally accepted, conservative, tested, sound, fit principles. there are only the following elements that i feel strongly about. everything else is up for grabs:

1. this protocol should by dynamic, not static
2. it should employ the use of a fit bike that adjusts in an x/y axis: exit cycling, serotta, guru dfu, rob king, et al.
3. it should be organic, and test systems, just like our FIST tri bike protocol. this means the output is: here your core four fit coordinates, and assuming "this" handlebar configuration (width, reach, drop); "this" stem length and pitch; x millimeters of spacers/headset top cap under the stem; the stack and reach of the road bike you're looking for is Y and Z.
4. a proper road bike fit output ought to satisfy all riding positions: seated/tops; seated/hoods; seated/hooks: standing/hoods; standing/hooks.

i've got part-2 of the protocol dialed (taking fit coordinates and matching them to road bikes for sale). we have a new, interactive, stack and reach database just about to go to beta, and both fitters/retailers as well as manufacturers will have preferences, control panels, etc.

what i want to know is this: what is important to you in terms of part-1 of the protocol? generating fit coordinates, i'm talking about. who's a proponent of KOPS? who thinks KOPS has no place in a protocol? what are your tried and true methods of generating fit coordinates that you feel are critical to keep?

we'll probably move our saddle height protocol right over from tri to road, but with a slightly different (knee) angular range, and with road bike setback. however, if you don't use KOPS to determine that setback, what's your preferred method?

likewise, cockpit distance and bar drop. what would you like to see in a protocol, taking into consideration the "mandate" that we tackle each axis, each parameter, individually, that is to say, we'll look at cockpit distance distinct from handlebar drop, distinct from saddle setback?

if you would, just post your thoughts here, and i thank you in advance.

Dan Empfield
aka Slowman
Last edited by: Slowman: Jul 1, 11 12:04
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Re: Road fit protocol [Slowman] [ In reply to ]
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OK, you asked for my thoughts...

I started doing bike fits about 15 years ago, having learned from John Allis and Peter Mooney. I then had a chance to ride with a few of the people I had fit and abruptly stopped fitting people 'cause what I saw told me I was doing no good at all. Having the best tool in the world means nothing if you don't know how to use it - that holds for the bicycle too. Bike fit doesn't count if the rider doesn't understand how to sit on a bike or where their weight really rests.

Riding a bike is simple, or at least I'm told. This is the assumption which allows bike fitters to deal with fit numbers and not with riders and technique. Over the last few seasons I've observed a lot of riders, many of whom have had professional fittings. If cycling is so simple, why do so many people do it so poorly? My answer to this is very simple, nobody ever explains why it goes wrong, and thus it continues to go wrong. I'll give one simple example - too much weight on the handlebars. Watch people ride their bikes, count the ones with relaxed upper bodies and the ones with straight arms and their torso weight on the bars - most have their weight on the bars. If you watch the same people sitting at their desk, you see them putting their weight on their feet under them, not on their desk or keyboard, so they know how weight transfer works, they just haven't applied it to the bike. The reason is also simple, most people don't trust their pedals. The pedals move (the floor under their desk probably doesn't) so they feel like they are falling and the defense for that is to find something solid to put the body weight on - the handlebars! Teaching people how to trust their pedals falls under the heading of coaching, not fitting, but until that works I find the rest of the fitting to be damn useless.

Somewhere in that book "how to be a bike fitter" there should be a chapter about riding with clients and seeing what good you are (or aren't) doing. When I started back into doing fittings I thought I could teach people all sorts of things in an hour. What I found was that basic posture, getting the body weight on the pedals, keeping them from going toes down and keeping the upper body relaxed is far, far better than most fitting will ever do (I've taken to asking people where they were fit). But dealing with numbers and data points is something that can be put into a fitting protocol, so I'm damn sure this will never happen...
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Re: Road fit protocol [Ti Designs] [ In reply to ]
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i want every point of view. even if the opinion about the best bike fit protocol is that there's no possible workable bike fit protocol.

this, because there may be a creative way to get to the goal, we just haven't found it yet. maybe there haven't been enough creative brains in the same room in the same time, sweating over the problem.

this forum, and this thread, is what i hope will be that digital "room" in which a lot of good brains bang out bike fit solutions. we have a slowtwitch forum none of you can see. it's for web and app developers. we solve problems in that forum we can't solve individually.

so, thanks for you view. it's more helpful than you might think. unless a road protocol solves the problem you may consider insoluble, we haven't gotten there yet, and i have more work to do.

Dan Empfield
aka Slowman
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Re: Road fit protocol [Ti Designs] [ In reply to ]
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I wholeheartedly agree that teaching people how to ride their bikes is crucial to the bike actually working for them.
This falls into part of the bike fit, especially for road bikes.
I have a lot to share in this matter and will post again later once I'm back from some training.

Jonathan Blyer,
ACME Bicycle Co., Brooklyn, NY
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Re: Road fit protocol [Ti Designs] [ In reply to ]
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I agree that there are many recreational and serious cyclists that have to get more comfortable and relaxed on their bikes. The goal of most bike fits is to get the client more comfortable and efficient on the bike, that seems like a pretty clear and simple goal. (may not be simple to achieve, but simple in concept) I think that coming up with a protocol isn't impossible, but like the tri fit axiom of "FIT, TRIM AGE GROUP ATHLETES CAN EASILY ADOPT THE SAME POSITION AS THOSE RIDDEN BY PROS" there needs to be an asterisk beside the protocol as far as people who do not fit the "comfortable being on a bike" category. I fit a lot of people who don't fall into the fit, trim age group athlete (and many of them have flexibility issues and maybe a few extra pounds on them). Do I fit them the same as someone fit, trim and with a good level of comfort on the bike? Of course not. Does it make my fit for them any less important than someone with 20 years of riding experience under their belt?
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Re: Road fit protocol [jeremysimmons] [ In reply to ]
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Hello and sorry for my english sometime not very good.
I think that with some experience (shared is better), we can have a good road fit protocol. After, of course, it's the fitter's job to make the difference between a pro or age-grouper or recreationnal, sprinter, climber, puncher ......
It's also the fitter who decided what he want to do with his fitting and it's not forbidden to tell people how to ride ! It's just a matter of time you want to spend in the process, how you follow the athletes you fitted and quality/cost you want.

-----------------------------------------
Joel Steve
Fitter for the French Triathlon Federation
Fitter for AG2R Pro Cycling Team
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Re: Road fit protocol [Slowman] [ In reply to ]
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I'm a firm believer that KOPS has no place in any professional bike fitting. There is absolutely no real science behind it and it has only seen such success IMO because there has been no easy alternative to it. It's been adopted out of convenience. This isn't to say that KOPS yields a bad position, it just doesn't necessarily cater to the riders specific needs. It's the equivalent of saying that the ideal seat angle for triathlon riding is 77 degrees and I'm going to just set everyone up at 77 degrees. Yes the position may be fine, it may actually be perfect for that rider, but without experimenting with other seat angles, it is not a thorough process.

I've adopted the basic procedure of a FIST bike fitting for road bikes and found that it works extremely well. The measurement landmarks and metrics are a bit off for road fits, but the procedure remains generally the same. The only real additions that I make is a lot of coaching on proper cycling form and I assure that the fitting allows the rider to take on this good form.
As we all know, road bike fits require the riders core to support the weight of the torso. Set up a road cyclist with too steep of a seat angle and the core will not be strong enough to support the torso and the arms will have to do some heavy lifting. It has been my experience that riders with weaker cores are more comfortable with slacker seat angles and those who have stronger cores may prefer a seat angle just about anywhere on the seat angle continuum.
There isn't necessarily a direct correlation to a fit person or a non fit person here, I'm just talking about core strength and the ability to sit with good cycling posture. A rider with a strong core can get away with a more forward position should they choose it.
I set up a guy a few months ago who has terrible core strength but who just won a two or three month long Thursday night race series. The guy is super fit, skinny as can be, he just has a weak core and struggles with good cycling posture. He's kind of stuck with bad habits. I set him up on the slack side because this was where he could hold decent posture and also where he felt the best. He described the slacker position as being 'more stable'.


I follow the same basic steps for a road position as I do for a TT position. I have the EXIT bike so I typically pick a saddle set back to start with and set up the reach and drop very conservatively. I'll set the seat height first, then will experiment with handlebars. All the while I'm coaching the cyclist on posture, reminding them to drop the heal, tilt the pelvis forward, engage the core and relax the arms. As I set the drop I have the rider try out each of the three hand positions along the way, ensuring that they have all the proper 'tools' at their disposal as we go through the range. As we go through these steps, if the location of the contact points makes it difficult for the person to hold proper posture, then we've gone too far and we back off. Once we get a baseline position, we'll try some steeper seat angles. Typically the rider will have a strong preference for on seat angle over the others.


I think that a FIST protocol for road fits can certainly be made but we need to find a way to incorporate more aspects of cycling technique into the protocol than what has been done for Tri fits. As another poster said, poor technique can really screw up a riders comfort even if the fit is perfect.


I'm interested to hear what others have to say on the matter and excited to help develop this protocol.











Jonathan Blyer,
ACME Bicycle Co., Brooklyn, NY
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Re: Road fit protocol [jeremysimmons] [ In reply to ]
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jeremysimmons wrote:
I think that coming up with a protocol isn't impossible, but like the tri fit axiom of "FIT, TRIM AGE GROUP ATHLETES CAN EASILY ADOPT THE SAME POSITION AS THOSE RIDDEN BY PROS" there needs to be an asterisk beside the protocol as far as people who do not fit the "comfortable being on a bike" category. I fit a lot of people who don't fall into the fit, trim age group athlete (and many of them have flexibility issues and maybe a few extra pounds on them). Do I fit them the same as someone fit, trim and with a good level of comfort on the bike? Of course not. Does it make my fit for them any less important than someone with 20 years of riding experience under their belt?

I have to question how many fitters here spend a lot of time fitting pros. I also have to question the idea of two different fitting methods for fit riders vs. less fit riders. I find that a system based on needs and flexability works pretty well for all. The basic rule of keeping a rider within their own range of motion holds the same for the elite athlete at it does for the novice rider. The limits may be pushed for the pros, but time in the saddle and stronger connecive tissue makes them more injury resistant. A good example here would be any of the riders I've coached from novice to cat 1. As a new rider the emphasis is always on teaching the pedal stroke. Any of my riders (and a lot of people I've fit) knows that increasing the angle at the hip (getting more aero) means the one leg pedal stroke drill gets harder. My advice to new riders is to forget about getting aero, sit up and learn how to pedal the bike. Once the pedal stroke is established, it's probably time to move the rider lower, which almost always is the case.

While we don't agree about many things, I think Serotta's flexibility based fitting method is a good starting point for any fitting protocol. It's lacking in a few key areas (rider setback never seems to get much attention - I don't get that) but if you are shopping for a set of rules by which to put any rider on a bike...
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Re: Road fit protocol [Ti Designs] [ In reply to ]
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To clarify, the final riding position between a rider with flexibility issues and someone who does their homework when it comes to stretching will be different, but how we arrive at those positions will be through a similar process. You are absolutely right when it comes to the number of fitters regularly fitting pros. In my experience (and probably that of every fitter) is that most bike fits are done with "average" riders, not "pros". I also agree that for most recreational riders there should be minimal regard to being aero, and again, this will be for a large number of fits on novice riders. The question should always be "what are the specific outcomes regarding position on the bike for this rider".
Last edited by: jeremysimmons: Jul 2, 11 19:43
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Re: Road fit protocol [jeremysimmons] [ In reply to ]
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I'm fitting around 40 pro cyclist (12 are in the Tour de France this year), the female French champion on road (and the 3rd), around 10 pro triathlete (FranÁois Chabaud just finishing second at IM France with a new bike course record), the French triathlete female champion on long distance, the French long distance team ....
However the protocol is still the same than for fitting average athlete, it's just the ratio confort/performance/ability that change and where you choose to go with the limit.
And with the pros I'm not spending more time fitting them, it's just that I follow them more closely and with 2 or 3 or more fit in the year.

I did the FIST session in 2007, learned also with Todd Carver from RetŁl (I use this system since 2008), Rod Cedaro from tri-Trainig Australia long time ago and I'm also in touch with Andrew of BikeFit.

It's a really good idea to share ideas and thoughts here. Thanks Dan ;-)

-----------------------------------------
Joel Steve
Fitter for the French Triathlon Federation
Fitter for AG2R Pro Cycling Team
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Re: Road fit protocol [Slowman] [ In reply to ]
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Slowman wrote:


likewise, cockpit distance and bar drop. what would you like to see in a protocol, taking into consideration the "mandate" that we tackle each axis, each parameter, individually, that is to say, we'll look at cockpit distance distinct from handlebar drop, distinct from saddle setback?


You canít do that on a road bike because hand position affects seat position, or more accurately, effective saddle setback. Unlike a tri bike, which is a relatively static position, a road cyclistís position is more variable. You can set saddle height and setback, but the moment you change hand position, whether it be reach or drop, youíll have changed the seated position as well. They are intertwined, as are all things when it comes to road fit.

Letís talk setback, as this is such a crucial part of road bike fit. I think itís safe to say that KOPS is gone. From there, youíll find a lot of opinions on what the proper amount of setback, or what the range of setback should be. I believe Retul has enough normative data to provide a good starting point for most of the ranges weíre looking at, but I find their range for setback to be too narrow. Doesnít matter, though, because before you even begin talking setback, you need to define where the riderís hands should be when measuring. On the hoods? Drops? Change that position, and youíll change the riderís fore/aft position.

Letís say weíre placing the riderís hands all the way out on the hoods. How much bend in the elbows do you want? This will affect the riderís fore/aft position. How much resistance should the rider be experiencing? This will often affect both knee angle and effective setback (which is why we take measurements at varying levels of resistance). How will you measure setback? Statically or dynamically? Those two will likely produce very different results. The key thing to remember is you canít set saddle position and simply move on. The moment you begin changing a riderís hand position or, more importantly, their pelvic tilt, youíll have changed both the setback measurement, and the knee angle at DBC; sometimes dramatically.

Letís move on to Pelvic tilt. Itís the one thing we canít accurately measure (sans driving multiple pins into the hip), but itís absolutely a top priority for a proper road fit. Without sufficient anterior (forward) pelvic tilt, the rest of the fit is folly because you cannot achieve a balanced, efficient position without first getting the rider to rotate the pelvic structure forward. Once you have this, the rest of the fit is actually quite easy, especially reach and drop, as the hands fall comfortably into position without needing to support much upper body weight. Of course, you canít achieve pelvic tilt without sufficient saddle setbackÖor reachÖor drop Ė they are inter-related and cannot be separated into their own neat compartments.

Like another poster, I, too, have revised F.I.S.T. for road bike fit. Itís worked well for lo these many years and, while I sometimes tend to dictate (or really, ďencourageĒ) positioning a little more with road bikes, allowing a rider to find their own position generally results in a good overall fit. Youíll find that, for effective seat angle, 73 degrees is to road fit, what 79/79.5 degrees is to tri fit. Seat angle is where American bike manufacturers need to wake up a bit, especially with smaller bikes. Cervelo gets it right Ė every bike, regardless of size, is at 73 degrees. From there, I have plenty of room to move a rider fore and/or aft. Anytime we get a call to fit an entire team, if itís sponsored by an American brand, I let them know Iíll be needing some way-back seat posts for most of the riders. If thatís not possible, you get what youíll see on most American designed/engineered bikes, seats pushed all the way back on the rails for the majority of the team.

If needed, I can achieve a forward ďcritĒ fit with a 73 degree angle bike; I canít always get where I want to go if Iím starting at 74, 74.5, or even steeper.


Where do we go next? Range of knee angles? Reach? This will be fun with lots of opinions and experiences, I think. Not as straight forward as tri or tt fit. I suspect Iíll learn a thing or two along the way.

Jim Manton / ERO Sports

Aero Tidbits posted on Instagram & Facebook
Last edited by: JM3: Jul 4, 11 1:36
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Re: Road fit protocol [JM3] [ In reply to ]
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So it looks like saddle set back is going to be the most contentious issue to start. Regardless of where we end up, or the process to get there, we need to have a starting point. What do we want to use as a starting point? Some ideas Iíve heard thrown around over the years (some better than others, donít judge!) Using a virtual seat tube angle, nose of saddle 5mm behind the BB, using KOPS, saddle clamped on centre of rails, using their current saddle setback as a baseline? Virtual seat tube angle makes the most sense to me (and follows the process for the tri fit) What are everyoneís thoughts?
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Re: Road fit protocol [Slowman] [ In reply to ]
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I confess that I use KOPS, largely because that's the way I was taught. I'm open to alternatives.

My only (small, all things considered) beef with FIST is the set of initial conditions: this clip-on, this stem, this spacer stack. That is to say, I understand the reasons behind the initial conditions, but I often have to move a bit beyond them. If the customer's question is, "Which Cervelo should I purchase?" I end up doing a lot of math in an effort to determine which stem/clip-on/spacer stack will yield a workable bike for that customer's optimum position.

In a road bike fit, I'd think that stack/reach to the bar would be a pretty great set of numbers. I confess that I've dragged my x-y tool around the shop, just to see how things might relate.

Color me intrigued.
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Re: Road fit protocol [driver8] [ In reply to ]
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I hope you all forgive me, I'll be following this thread pretty closely. I might chime in and hopefully I'll impart something of value. I've recently fallen into bike fitting/ bike shop work as a career... always thought this would just be a hobby. But I do have a few questions:

1) If you're not using KOPS, what are you using to set saddle set back?
2) I realize the issue of riders not riding with proper technique, and to insure comfort with the bike fit it's imperative. I've been trying to answer this question for a few months now. I don't think the answer is turning all fitters into coaches. That's effectively what is being talked about. I haven't been to FIST, and I hope to go soon, but is this part of the FIST curriculum? Teach each client how to ride like Torbjorn?
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Re: Road fit protocol [txdillard] [ In reply to ]
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As some of you know, I teach a third day at the FIST seminars occasionally and it has always suprized me, how in each class, we end up discussing road bike fits. I have been doing road fits since the late 70's [yea, I'm old] and have, like many of you, gone through several systems and fads. Over the years I developed my own system for seat setback but while talking to Dan the other day, I was wondering just how others did arrive at a seat setback position. This thread should be interesting to follow as a lot of good information pours in. My system envolves locating the point that the Quad group and the Hamstring group switch over and setting that point at 12 o'clock on the cranks. It's fairly easy to find and tune and consistantly frees up several watts of power. I would be interested to hear from anyone that has taken my class on this and to find out if it is easy or too complex to go into further without specific hands on teaching.
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Re: Road fit protocol [jeremysimmons] [ In reply to ]
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jeremysimmons wrote:
So it looks like saddle set back is going to be the most contentious issue to start. Regardless of where we end up, or the process to get there, we need to have a starting point. What do we want to use as a starting point? Some ideas Iíve heard thrown around over the years (some better than others, donít judge!) Using a virtual seat tube angle, nose of saddle 5mm behind the BB, using KOPS, saddle clamped on centre of rails, using their current saddle setback as a baseline? Virtual seat tube angle makes the most sense to me (and follows the process for the tri fit) What are everyoneís thoughts?

My point, along with the difficulty in determining both how to measure a riderís fore/aft position and what range a rider should fall within to be properly positioned, is that road bike fit canít be compartmentalized the way tri bike fit can. For a proper F.I.S.T. fit on a tri bike, you set the seat angle and find the riderís best height for that angle. For the most part, youíre done with saddle position at that point (for that specific effective seat angle anyway) and you move on to reach and drop. Great, that works just fine and we donít really care all that much what the changes in reach and drop do to a riderís fore/aft position (within reason, anyway). You canít do that with a road bike fit because that fore/aft measurement will change and does matter, at least according to current beliefs on how a road bike should be fit.

Perhaps the question(s) that need answering, or better definition, is what does the fore/aft measurement/protocol provide? What are we actually trying to achieve? How might we find what weíre looking for in another manner with a well-defined set of parameters that are easily repeated? For instance, I utilize Retul. Their fore/aft measurement is titled ďKnee Forward of FootĒ defined as: The average of each stroke's difference between the horizontal positions of the knee and foot when the foot is in the forwardmost position where a positive number represents the knee being more forward then the foot. The stated range for a road bike fit is between 0 and -10mm as measured by Retul assuming proper sensor placement (a big assumption based on some of the marker placement Iíve seen). This range, in my experience, is too narrow. In fact, Iím less concerned with this measurement as I am with proper pelvic tilt and overall balance across the bike. Sometimes people fall into Retulís range, sometimes they do not. My job is to find the riderís optimal position, not just place them in a generic spot that works for the average person (one of several reasons why KOPS is no longer a valid fit protocol).

So, if weíre seeking to come up with a better set of protocols, a way to ďbring it all together.Ē Maybe we should first question what weíre measuring and why? Then again, maybe this isnít what Dan is after; itís potentially a big can of worms.

Jim Manton / ERO Sports

Aero Tidbits posted on Instagram & Facebook
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Re: Road fit protocol [JM3] [ In reply to ]
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Quote:
For instance, I utilize Retul. Their fore/aft measurement is titled ďKnee Forward of FootĒ defined as: The average of each stroke's difference between the horizontal positions of the knee and foot when the foot is in the forwardmost position where a positive number represents the knee being more forward then the foot. The stated range for a road bike fit is between 0 and -10mm as measured by Retul assuming proper sensor placement (a big assumption based on some of the marker placement Iíve seen).

Correct me if I'm wrong, but that sounds a little like a re-worded KOPS setback?
Last edited by: jeremysimmons: Jul 5, 11 6:24
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Re: Road fit protocol [JM3] [ In reply to ]
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Several years ago I had a set up going where I placed digital postage scales underneath the feat of my fitting bike. I used the scales during my road bike fits and we fitted many cyclists with this system including Mr. Jordan Rapp. The purpose of the scales was to determine the riders center of gravity at a given position. We would set someone up on the slack seat angle side and get the seat height and handlebars in a good position. We would then zero out the scales from the weight of the fit bike and then put the rider back on and ask them to stay still. We would gather the weight distribution to each scale and then use excel to calculate where the COG was with respect to the bottom bracket. Our theory was that novice cyclists and cyclists without good core strength would prefer seat angles that positioned their COG just behind the BB and that more experienced and fit cyclists would prefer a COG just on top of or in front of the BB. This largely held true and we had good success with the system. We eventually stopped using it because it became a distraction to the fittings and we weren't actually using the COG data to help determine the final position, we were just relying on what the rider preferred in the first place. I'm not saying this should be used in the methodology going forward, but that others would find the information interesting.

Jonathan Blyer,
ACME Bicycle Co., Brooklyn, NY
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Re: Road fit protocol [John Cobb] [ In reply to ]
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John Cobb wrote:
My system envolves locating the point that the Quad group and the Hamstring group switch over and setting that point at 12 o'clock on the cranks. It's fairly easy to find and tune and consistantly frees up several watts of power.

So it's a system based on the reciprocal inhibition between the quads and hamstrings, but why place that at TDC?
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Re: Road fit protocol [Ti Designs] [ In reply to ]
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I have a 4 channel EMG unit that I've used for years. I noted over the years that setting the seat position to make the crossover point at 12 o'clock seemed to consistantly give more power. I finally stumbled onto the fact that you can feel this point of flex right under the Itchia Tract very easily so that you don't have to rig up an EMG to set it. You can make a change as small as 1 mm in seat height or fore/aft and spot the change with just a little practice. In a road position, this generally sets the setback at about 72.5 - 73 degrees and on a tri bike you can find the point at about 78 - 80 degrees depending on upper / lower leg ratios. It is the only way I have found that can tell you where the last couple of millimeters needs to be set for maximum power. I try to stay fairly well versed in other systems and I think that as this thread continues we will all learn some valuable info. I don't think that I or anybody else has the perfect system yet but in the end, the consumers will benefit from our exchanges greatly.
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Re: Road fit protocol [John Cobb] [ In reply to ]
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I remember the way you showed us how to "feel" the exact point but it's not so easy to find at the beginning.
It need some practice and knowledge of body to really feel it.
But it's a very interesting way to explore.

-----------------------------------------
Joel Steve
Fitter for the French Triathlon Federation
Fitter for AG2R Pro Cycling Team
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Re: Road fit protocol [John Cobb] [ In reply to ]
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Hi John
Interesting technique.
Correct me if I'm wrong, but you are saying that you put this crossover point at TDC for TT positions as well as road positions.
What is it about a Road position vs. a TT position that causes the shift of about 6 or 7 degrees of seat angle if the crossover point is the same at TDC? Is this a function of hip angle?

Jonathan Blyer,
ACME Bicycle Co., Brooklyn, NY
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Re: Road fit protocol [jonblyer] [ In reply to ]
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I'm trying to think of a way to explain this because it is very easy to see and feel but harder to explain. I do think it has to do with hip angle but not because of pinching down the angle of the upper body. As you would rotate a Tri guy forward to keep the hip angle open, the angle of pressure to the cranks changes but by tuning this point the legs go over the top tight area and begin the drive into the cranks with more force. For a UCI racer with a seat setback, the setup is very much like a road bike, that's why I started going to a very deep drop, shorter stem for road racers. I'll try to think up a better explanation.
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Re: Road fit protocol [John Cobb] [ In reply to ]
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John Cobb wrote:
I noted over the years that setting the seat position to make the crossover point at 12 o'clock seemed to consistantly give more power.


That assumes a consistent ratio of muscle strengths and usage from one rider to another. As a coach of sprinters and climbers I find I have to alter saddle positions based on how they ride and the strength ratios of the stronger muscle groups. I guess in a forum full of time trial riders it makes sense to talk about power in it's generic form, but in a sport where people are paying big bucks on equipment it makes far more sense to find that optimal balance based on the individual.

A little side note: As this is a thread about finding a fitting protocol, what I'm talking about really doesn't fit in. There are plenty of fit studios that will take a few hours and put a rider into a "perfect" position based on whatever method they use - for that there must be some form of protocol. I start with the individual, working on the pedal stroke, muscle firing order and limiting duty cycle of each muscle group. With that established, using muscle groups in isolation gives a very clear picture of how position on the bike changes the output. Working at the gym, using machines to isolate muscle groups the ratio of strengths becomes even clearer. With that, and their riding style I look for a position that offers the best balance. As I've said, it's not something you can do in a few hours, but there are significant gains to be had.

In doing a basic bike fitting I look for a position that allows the rider to relax their quads at 3:00 (with the pedals stopped) and put their upper body weight onto the pedals using the glutes, while taking almost all of the weight off their hands. I use the example of sitting in an office chair, if your center of gravity is over your feet, your glutes hold you up - you don't see people sitting in chairs firing their quads all day. If you move your feet back and then lean forward, as soon as your center of gravity passes where your feet are on the ground your quads come into play (or you fall on your face). If you move your feet too far forward and lean forward your hamstrings pick up tension. When transferring your body weight to the pedals at 3:00, there's no advantage to having the other muscle groups working, if anything there's the disadvantage of increasing the duty cycle of the other muscles. Keep in mind that any muscle group that goes much beyond a 40% duty cycle is anaerobic by definition - blood flow doesn't happen under tension. This is why so many people claim their quads burn when they climb, it has little to do with power output, they simply haven't learned to limit usage of the quads...
Last edited by: Ti Designs: Jul 8, 11 12:27
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Re: Road fit protocol [Slowman] [ In reply to ]
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Dan sorry for the delayed reply. I have been doing a lot of road bike fits lately and I have adopted John Cobs method of timing the muscle change over from hamstring to quad and some of Steve Hoggs method for balancing for and aft weight. Interestingly enough every time I time some one at TDC by repositioning their saddle they also become perfectly balanced and able to remove their hands from the drops momentarily. Handlebar height seems irrelivant at this point as the hands are now only required for steering not holding up the torso. The bars can now be lowered to improve aerodynamics. I also tip their saddle nose up at least two degrees. This is also from John and it worked for me and has worked for most of my road bike clients. This approach is basically all hands on fiddling with the exception of the proper knee angle measurement. I don't know how you would capture this in a fit protocol.
Cap

http://www.fulltiltfitting.com
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