Aaah...but you see, you can do it just as easy as the seat measurement without the jig. You just need an angle finder and a tape measure.

OK...let's try "The Unified Theory of Saddle and Aerobar Measurement - Take II". Let's start with some proposed language and pics. As discussed earlier in this thread, here is the proposed language for section 1.3.013:

1.3.013 - The peak of the saddle shall protrude no further forward than 17 centimeters in front of a line passing through the bottom bracket spindle and inclined rearward at an angle of 78 degrees from the horizontal.



Boom. That's it. No exceptions for track races, etc. Great...so, let's do the same for the front end. Here's my proposal for section 1.3.023:

1.3.023 - For road time trial competitions and for the following track competitions: individual and team pursuit, kilometre and 500 m, an extension may be added to the steering system. The extension shall protrude no further forward than 66 cm in front of the intersection of limit line B (as set in article 1.3.022) and a line passing through the bottom bracket spindle inclined forward at an angle of 78 degrees from the horizontal, with the other limits set in article 1.3.022 (B,C,D) remaining unchanged. A support for the elbows or forearms is permitted (see diagram <<Structure (1B)>>).

For road time trial competitions, controls or levers fixed to the handlebar extensions may extend beyond the 66 cm limit as long as they do not constitute a change of use, particularly that of providing an alternative hand position beyond the 66 cm mark.




OK...so that's it. Simple, easy to measure, scales for the size of the rider.

The jig can be used as described above to check both measurements...or, you can just pull out the angle finder and a tape measure :-)

BTW, the example above used 78 degrees as the reference and the 66 cm is calculated to provide 75cm of extension at a height of 67cm (top of a typical 700c tire) assuming a bottom bracket height of 24 cm. If a different angle is chosen, then the forward extension dimension (in this case 66cm) can be calculated from the equation:

Forward extension = 75cm - (67cm - 24cm)/(tan angle)

What do you think?

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http://bikeblather.blogspot.com/

if you had the fixture, i suppose you could flip the bike around (assuming the 1.3.013 and 1.3.023 rules use the same angle) and pretty well eyeball the place on the wire that's at the height of the saddle. or if you're not sure you sit a level on the saddle and see where that point crosses the wire. then you measure from that point to the extensions and see if it exceeds 66cm.

in this case, tho, fixture would have to be leveled, whereas it would not have to be with 1.3.013.

it would be nice to be able to easily measure this, tho, using a landmark on the bike. for example, a distance from the saddle nose to the bar extensions, that changes as a function of the saddle height.

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Dan Empfield
aka Slowman

Nope...no need for leveling, all you need to do is grab your 48" drywall T-square out of the garage and slide it up and down one of the vertical members of the jig :-)

Assuming the vertical bars are sufficiently square with the baseplate, that is....




That's the "cheapo" solution. On the "harp" rig, it wouldn't be too difficult to incorporate a horizontal bar that slides vertically, would it?

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http://bikeblather.blogspot.com/

okay, i think this is do-able.

but i do think there is one hitch in the get-a-long, and that is determining a way for the end user to set up his bike legally. there needs to be an easy way for him to do this, and remember that he doesn't have the fixture.

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Dan Empfield
aka Slowman

It would be easy enough to check all dimensions by putting the bike up against a wall in the corner of a room with the tire (or furthest point forward) touching the wall. Measure to all critical points on a plane horizontal to the floor and then measure the height off the floor. Put these values into a form on a web page and hit submit. The script could easily calculate whether the bike is legal or not and give a warning in case one of the dimensions is close to being out of range. If the values aren't close to being over the limits there shouldn't be any worry. If they are close, the rider should verify their measurements to be correct or seek another way of verification.

On a side note: Has anyone seen the movie "The Flying Scotsman"? It seems that most of the rules in question were created in this movie in an almost comical way to combat Graeme Obree's riding positions. I just got done watching it for the first time and all I could think of was this thread...and what a great movie it was.

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http://www.kickballracing.com
I have many hobbies...make that too many.

Are you referring to just the bar measurement, or to both the saddle AND the bar measurement? If it's just the bar measurement, I don't see how it's appreciably more difficult than checking the seat position.

Besides, since when have these rules had the "end user" in mind ;-)

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http://bikeblather.blogspot.com/

a little t-slot al strut would be cheap, realatively light and fast to assemble/teardown.

but imho the 66 needs to be longer...

rmur was talking his dimensions but mine are similar - 7cm behind bb, 76cm c-t of saddle - extensions ~90cm in from of bb:



that is an old bike (without the saddle in the correct location), but the bar dimensions are still the same as mine today...

g

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greg
www.wattagetraining.com

greg,
What's your elbow angle in that position? How tall are you?

Someone must have a database of saddle heights, extension + overall height etc. for comparison???

Well...as I said above, both the angle and the linear dimension are "in play"...but IMHO, you aren't going to get the UCI to go that far. Don't forget, the whole point of the extension rule is to prevent the use of a Superman, or even closely Superman-ish position.

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http://bikeblather.blogspot.com/

Ric,

I am 6' and the elbow angle is close to 120 - will pull a bike+rider pic and measure.

Tom,

It really isn't superman. The drop pretty much negates that (as the superman was more arms inline with torso).

G

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greg
www.wattagetraining.com

pic as promised:



g

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greg
www.wattagetraining.com

it appears this revisiting of the rule is back in play. i have a question for you all, and i'm going to have to ask that if you want to be up to speed on this you go back and revisit the thread. but in general, here's the rule that may be subject to change, that is, here's the change we all decided we would like to make back at the end of 2007:

1.3.013 - The peak [or nose] of the saddle shall protrude no further forward than 17 centimeters in front of a line passing through the bottom bracket spindle and inclined rearward at an angle of 76 degrees from the horizontal.

You use whatever angle you want, it doesn’t have to be 76. The point of the 17cm part is to keep somebody from riding with a 76° seat angle but putting a banana saddle on his bike to thwart the rule. You would use the image several posts above, it would be the new commissaire’s jig. It’s got 2 parallel wires, we call this jig a “harp,”, and you roll the bike up so that the BB is in line with the rear wire, and the saddle nose cannot protrude past the front wire. This harp conforms to the rule above. Easy to build. Easier than the current jig.

1.3.023, a couple of ways to do this. Tom A.'s view was that you angle a wire forward, 78°, you add 66cm to that point, that's your bar end limit. the other idea is to just say you get saddle height + 5cm. That is, take BB to the top of the saddle, midway between fore and aft, that’s saddle height. You get that amount + 5cm max from saddle nose to the end of the extensions.

my question is this. in both cases, the saddle height + 5cm, and the 78° forward angled line + 66cm, can there be yet another wire that represents the forward protrusion, so you don't have to measure? seems to me there might be with at least the first case, that is, saddle height + 5cm, as long as you normalized saddle height as some spot above the ground. in other words, if you assumed that ALL bottom brackets emanated from a point so many centimeters up that wire from the ground, then could you angle a wire near the front of the harp that represents, at every point from the forwardmost of the 2 parallel wires, saddle height + 5cm?

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Dan Empfield
aka Slowman

Did you get contacted by the UCI?

A few weeks ago, I took advantage of a Twitter exchange between Taylor Phinney and Brian Cookson on the subject of the fitting rules to reply with links to your 2 articles you wrote way back when :-)

The wonders of social media, I guess...

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http://bikeblather.blogspot.com/

i've been working with the person at a large bicycle company who's in direct contact with the UCI, and just emailed me today saying that he thinks there may be a window of opportunity now. so, i really need both a rule, and a commissaire's fixture solution, for 1.3.023. you and i were, at the time, discussing the merits of either saddle height + 5cm versus 78° forward tilt + 66cm. i don't know that one is terribly better than the other, but i do think if either one is able to be represented by a third "wire" on the harp, that one probably has the inside track.

so, i need a decision on which version of 1.3.023 along with the formula for constructing the harp's 3rd wire.

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Dan Empfield
aka Slowman

Are they open to just getting rid of one or the other rules? (My vote would be to get rid of the seat rule, or just make it the same as all the non-pursuit track events)

To do it right, a look at what the rules are intended to accomplish would be a good start...

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http://bikeblather.blogspot.com/

right. but this current opportunity - or what might be an opportunity - doesn't exist in that world you're talking about (the world i prefer). this apparent opportunity lives in a world that we can either participate in or not, but works according to its own closely scribed rules of what's possible.

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Dan Empfield
aka Slowman

Short fuse? I might not get a chance to seriously look at it until later in the week.

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http://bikeblather.blogspot.com/

seems like this is kind of a 1-day turnaround. right people in the right place at the right time. i think i'm going to sticky this, see if any of the brainiacs can do a little trig, and make me a little equation describing where to put that third wire. i think it's just a trig equation, maybe, if we take the harp, place the BB in it, on that rearward wire, make it a cartesian graph with the BB (0,0), and we need an equation that describes the slope, past which the extensions cannot exist.

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Dan Empfield
aka Slowman

I only skimmed the thread but I do have questions in my mind as to the intent of the rules. I would imagine that one of the goals is to prevent riders employing extreme "superman" positions as well as preventing the development of some pretty unconventional frames. The conversation in this thread seems to focus on limiting how steep one can ride and how far forward bars/saddle can be placed.

The approach of saddle height + 5 as I understand it does more to prevent superman positions than the forward tilting harp one does. Under the forward tilting harp approach, there is nothing preventing riders from riding with extremely slack seat angles and leaving the bars far forward. While I think most would not advocate riding such a slack position one could imagine riders/teams exploring ways to get as aerodynamic as possible even at the expense of power in certain circumstances.

If the rules aim to establish/maintain aesthetic positioning norms they need to account for whatever bizarro ideas may come up. That's a long way of saying I would think the bar position needs to be tied in some scalable way to the saddle position. Unfortunately I think this makes for a more challenging fixture.

My issue with the +170mm is that it still allows circumvention of the intent of the rule with saddle choice.
If what we're trying to avoid is the superman position then the easiest method is just to limit elbow angle. That way there is no inconsistency across the rider height range.

If we must set a limitation on saddle angle then a 78deg on the fixture with 90mm wide prongs in the z-plane to fix the ischial contact area at that angle. Then riders aren't forced to make saddle compromises (like using an Adamo when it doesn't suit) to get the most out of the rules.

As it is short riders can get well past 80deg effective under the current rules with no real limitation on reach.
And now the Sitero and Tritone push the boundaries further.

Link to workings for reach angle - based on some quick and dirty work with anthro data from 4000 members of your military. Defining height range to work to and a very crude look at variation in reach.

My thought is that a start point should be defined - either a median rider or shortest rider and the reach progression is on a 60deg line forwards to allow for the progression in reach as riders get taller.

I think using some element of the current rules as a start point might help with the move to a new system.
My experience is that an averagely proportioned rider of 180cm can usually fit in the current box at 50mm setback on an Adamo with 800mm reach from the BB.
Which means an effective setback of 170ish (50 +110mm length to 90mm wide point).
Then if we take a 770 saddle height at 78deg to define the y and x is 800

And I think reach should be defined to end of shifter body, regardless of whether lever is R2C or not.

Sorry for the jumbled thoughts, haven't had time to marshal my usual linear writing style.

I disagree, as there are those of us that are not averagely proportioned. I can be a case in point at 175cm, with arms and legs that are shorter than avg upper halves and longer than avg lower halves. I could seriously use both, a saddle further forward(0 to -2cm) and extensions longer than 80(as previously defined, not currently defined) there is a serious loss in power for me when I move saddle back.

regarding extension length, I think it is stupid to say maechanical and di are measured to same spot. if you hold mech levers at end, every little bump causes a shift, large bumps cause a shift in multiples. you cant hold the levers at the ends. your hands(fingers) can wrap around them but your hand really remains behind the point of rotation, just as it would with di2. mech folks now essentially lose just a hair over 5cm extension with mech which means 70cm extension length is saddle is forward of 5cmback. so folks like me, either have to give up a boat load of power or have arms angling back or precariously perch hands on nothing in front of shifters.

The problem I see with the saddle height + 5cm is you would quickly end up penalizing the same riders that are penalized now, i.e. taller people with short legs/long torso. I'm 6'1" and inseam is 33" if I remember correctly. My saddle height is 733mm or so to where I sit (so probably 74-75cm to the middle of the top of my Adamo), which means your suggestion would give me 79-80cm of reach from saddle nose to shifter end, which is 5-6cm less than I have now if I put my saddle tip 5cmm behind the BB (it is actually 7cm behind now).

You will always get problems with people with different ratios between leg and torso length if you make rules based purely on bike measurements. You need to look at statistical data and see if you can somehow put something together that seems to be OK for people on both end of the spectrum, and if that's not possible you're really back to measurements on the rider on the bike (which is a pain for commisaires and will probably never be fair anyway since you can 'game' it and you will probably move around on the bike when riding anyway).

The other problem I see is that it might not be hard to build a jig with the angles you mentioned, but you're never going to get more than a few percent (maximum!) to actually be able to measure their bike at home and set it up correctly. Might not be a problem for World Tour teams, but you will get boatloads of riders showing up with illegal bikes in everything below the World Tour simply because they have no clue how to measure their bike to properly fit within the rules (let alone understand the rules). Look at how many people that can't even calculate the stack and reach of a simple -10 degree stem!

the thing here is, it's already been litigated. what we now have is a rule to keep the saddle back, and a rule to keep the aerobars back. it's not JUST to forestall the use of the superman position. you could ride in a typical tri position, as regards the rider's cockpit, but have that position moved way forward. the saddle nose rule prohibits this.

so, we have an opportunity, maybe, to help remake the rules in a way that is scalable, which the current rules are not. what makes the rule scalable is the use of an angular rule rather than an X/Y rule. we have 1.3.013 written. end of story. the only slight variation in the story might be the 17cm: should it be shorter, with the advent of the use of split rail saddles? or, we keep it at 17cm but just slack the angle back to 76 or 75 degrees. we're just fiddling with that rule, but, basically, that rule's written. aint gonna change.

then we have 1.3.023. no, the current rules does NOT penalize long torso riders, at least, not long torso riders ONLY. it penalizes EVERYBODY above a certain torso length, which means even normally proportioned riders above, say, 6' tall, or even a bit shorter. just, keep your eyes on the ball. we need to have a jig, simple to build, cheap to build, to send to the world's commissaires, that allows a bike to be rolled up to it and in 10 seconds the bike is either legal or it's not. so, i think if we just establish a distance that captures the great majority of riders we'll be good.

but let's say you get a rider who really is terribly inconvenienced by this. he then could, conceivably, move the saddle back a bit. but that would violate the rule. except if the rule was not 5cm beyond saddle height, rather the rule was just the placement of the front wire. this was tom a.'s point, or, at least it's the fruit of his point. the placement of the front wire is the rule, and then you can put the saddle fore/aft wherever you want as long as it does not go further forward than the middle wire.

if i have to dust off my high school trig and geometry because you rhodes scholars aren't any better at math than i am, fine. but what i'm asking for, here, is this: a formula for the placement of the front wire that represents a scalable line that prescribes the aerobar extension limit.

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Dan Empfield
aka Slowman

the problem with saddle height plus 5 is that it does not account for drop. someone, at any saddle height, with less drop is going to get more reach with x=y+5, I mean that is a simple 45 deg line starting at BB height 5 cm in front of the BB. if your drop is 10 cm you get x extension if your drop is 20 cm you get x-10 extension penalizing those that want to get flat and aero

"the problem with saddle height plus 5 is that it does not account for drop."

fine. anybody who wants to pay the aero penalty to get a little further out may do so. i really don't think you understand what's going on here. the rule as i'm contemplating it has a pretty luxurious cockpit availability, versus the current rule where you are extremely constricted. i think you're trying to find a problem, rather than helping to find a solution.

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Dan Empfield
aka Slowman