Do we need a new tri bike geometry?

Triathlon Forum
21

I know there are others but aren’t the majority of folks who need more reach riding canyon’s? We talked about it a bunch on here when the new speedmax came out but that bike is definitely reach/pad x challenged.

examples of bikes I’ve been working with when I help with fits that need additional pad reach include: Trek, BMC, Ventum, Cervelo P5d, QR, Canyon, Felt, Scott, Cube, Factor, Giant, Pinarello …

This is being resolved with extender plates, but I feel this would be better resolved with longer frame reach so that steering isn’t negatively affected as more mass is placed further forward.

1 Like
22

Example: https://www.instagram.com/...hid=N2ViNmM2MDRjNw==

examples: by my eye 3 of 12 males who were in kona last year had extended positions like your one example. maybe 1, or no, women pros rode that way.

maybe things have changed a whole bunch between last year and this year but i doubt it. furthermore, these people don’t keep cervelo in business. the readers of this forum keep them in business. how many of them will ride baekkegard’s position on the bikes they purchased? answer (in my experience): a number approaching zero. perhaps if we can demonstrate that certain new aerobars allow that position to be ridden in a more aero way; and if it’s sufficiently comfortable to ride that way; we’ll see a move. but to see that move everybody would have to be riding that aerobar (or aerobars) or moving to that position may well produce an aero penalty.

this all may change. if it does then we’ll have a new consensus position. but we don’t have it yet based on my evidence.

as for baekkegard and laidlow (and svensson, amberger, ditlev), they are exceptions to the rule. i’m happy to talk acknowledge the exceptions and we can talk about them, dissect them, argue them, measure them. but i’m only willing to acknowledge the exception if, at the end of it all, you’re willing to acknowledge the rule.

23

Watching Kona and seeing how many pro women were incredibly cramped in their shoulders and how much repeated scooting fore/aft was going on, I don’t think a majority of people are in good positions and I’m then not sure their bike fits should be looked at as a rule, but more so a moment in time that Progress in the way people are fit on bikes will supersede. Maybe if bikes came with longer pad reach, the rule wouldn’t be the rule - the bikes might be the problem. As long as people have to buy after market extension plates or expensive aerobars to accomplish these fits, there is a steep switching cost to a fit that many pros are finding more conducive to comfort and producing power. The rule, then, is a byproduct of poor bike geometry, not a result of knowledgeable consumer preference.

24

I don’t disagree in general, but I measured the seat angle of the new P5 with the saddle clamp in the centre, and it is ~76 degrees. No wonder any pro riding it has the saddle clamp and rails all the way forward. Cervelo’s web page does not seem to list it…I suppose because it is very variable with the new adjustable seat post clamps and saddle rails

i think that’s an artifact of the equipment. i remember back, 30 years ago, our biggest competitor was cannondale. they made a slack seat angled bike that had a control tech seatpost that you could flip forward or backward. but the entire bike was designed around the idea that you rode it forward, and everybody did. if you look at the entire rest of that bike, it was a geometric copy of what we made. so, at some point, some naive product manager decided (my own guess at how this happened) i can save the company money if i replace this $10 OE seatpost with a $4 OE seatpost. which you couldn’t flip forward. and the sales of cannondale’s tri bike died a quick death (because, again, cannondale’s retailers were naive as well, and didn’t know you would just replace the seatpost with one that placed the saddle forward).

move forward in time to the development of the P5, cervelo assumed the saddle most folks would buy is an ISM. if your bike didn’t accommodate that saddle you were in trouble. you rode that saddle at 76°. cervelo was right to place the seatpost in a position that centered around that style of saddle. if you look at the front of the bike, the stack and reach, it was right where it needed to be. when i rode that bike with a profile design tri stryke i slide the post clamp forward. the bike geometry didn’t change. how i sat the bike didn’t change. how i sat the saddle changed.

so, when you’re talking about making a bike that accommodates a more stretched cockpit, what you need to change is the bike’s reach and front center. you may need to increase its stack if you’re also going to raise the aerobars. it’s the front of the bike that needs attention if that’s your goal.

25

I think there are more with the extended cockpits then just a few ….

Jeroen

maybe. but when we take photos in profile of the pro men and women in big races we see way more riding in tried-and-true positions. but i’m always eager to learn. teach me.

From what just pops up in my head after having looked up to further into this.

Laidlow
Kanute
Baekkegard
Haug
Lionel
Menno Koolhaas
Rudy von Berg
Kat Matthews
Ellie Salthouse
Braden Currie
Kyle Smith
LCB, changed to a longer position somewhere this summer

Some further forward then others but all in a way have adapted their cockpit further forward.

Jeroen

26

Are the new generation of running shoes so good in cushioning while still being faster that quad muscles can be used more intense during the bike leg? It also seems that the bike times get faster, 4.00 to 4.05 are now possible for a lot of athletes. Does the positional change ask for a new tri bike geometry? More reach and more stack as well?
Are we on the edge of the need of a whole different design of tri bikes, will this create differences or new opportunities in aerodynamics, a different view of triathlon bike fit?

I think triathlon riders are riding steeper, not because it is better for running muscles, but because it is an overall better position for the power generation vs aero drag equation. Whether or not one runs after the ride.

But, as others have pointed out, UCI rules are also having a big effect on bike frame design. UCI rules are stifling innovation and if the UCI significantly loosened rider position rules for TTs, we would see big changes in rider position, and also in TT frame design.

If UCI rules allowed it, I think that riders would also ride somewhat steeper on road bikes, if frames were properly designed to accommodate steeper seat angles.

In the cases I meant UCI rules have nothing to do with it since a lot of these tri bikes are already UCI illegal.

Jeroen

27

Watching Kona and seeing how many pro women were incredibly cramped in their shoulders and how much repeated scooting fore/aft was going on, I don’t think a majority of people are in good positions and I’m then not sure their bike fits should be looked at as a rule, but more so a moment in time that Progress in the way people are fit on bikes will supersede. Maybe if bikes came with longer pad reach, the rule wouldn’t be the rule - the bikes might be the problem. As long as people have to buy after market extension plates or expensive aerobars to accomplish these fits, there is a steep switching cost to a fit that many pros are finding more conducive to comfort and producing power. The rule, then, is a byproduct of poor bike geometry, not a result of knowledgeable consumer preference.

your “so many incredibly cramped pro women” is a straw man. or straw woman i guess. what you say exist doesn’t exist. when i look at the positions of the women pros in kona last year (i gave you the link) i see no cramped positions, and those are mainstream bikes (canyon, cervelo, CUBE, etc.) the geometries were well suited to the positions those women rode. if you think lucy’s position is “cramped” and her bike’s geometry wrong, perhaps you can get in touch with her team and let them know how much time savings you’re able to give her if she and her bike maker only followed your advice.

28

There seem to be a continuous stream of pro athletes riding super steep seat angles. //

Not sure you are aware, but when triathlon bikes became a thing, and even before, all of us pros mostly rode at 80 to 90 degrees relative to the BB. Most the early Tri bikes had 80 degree seat tubes, and we moved everything forward from there. Then a rule came in about only being able to be 5cm in front of BB, so most of us settled on 85 or so degrees, nose riding the saddles at the time. We did a lot of road testing back then, and there were no noise coming at us from outside as to what we "should " ride, aka Slam, etc. We just gravitated to that very forward position and it worked, in speed on the bike, and better runs afterwards.

Then all the outside noise started to filter in, bike companies decided to split the difference in geometry between road and Tri thinking folks could then use the bikes for either(stupid idea) and for the following couple+ decades all of you that came into the sport just thought that is how it is and ought to be. The UCI was no help of course, but 99.9% of us are not obliged by their rules, so that should have been a non starter, except the bike companies thought it was…

SO now you have smart and in tune pros finally gravitating back to where we rode the bikes in the beginning, only now the institutional memory has been lost and it is a new fangled idea. Next thing I suppose is someone is going to take credit for this new wide angled pant leg folks are wearing, called bell bottoms I believe…(-;

29

Watching Kona and seeing how many pro women were incredibly cramped in their shoulders and how much repeated scooting fore/aft was going on, I don’t think a majority of people are in good positions and I’m then not sure their bike fits should be looked at as a rule, but more so a moment in time that Progress in the way people are fit on bikes will supersede. Maybe if bikes came with longer pad reach, the rule wouldn’t be the rule - the bikes might be the problem. As long as people have to buy after market extension plates or expensive aerobars to accomplish these fits, there is a steep switching cost to a fit that many pros are finding more conducive to comfort and producing power. The rule, then, is a byproduct of poor bike geometry, not a result of knowledgeable consumer preference.

your “so many incredibly cramped pro women” is a straw man. or straw woman i guess. what you say exist doesn’t exist. when i look at the positions of the women pros in kona last year (i gave you the link) i see no cramped positions, and those are mainstream bikes (canyon, cervelo, CUBE, etc.) the geometries were well suited to the positions those women rode. if you think lucy’s position is “cramped” and her bike’s geometry wrong, perhaps you can get in touch with her team and let them know how much time savings you’re able to give her if she and her bike maker only followed your advice.

To be fair, LCB position on her pink cube last year is very cramped. At least I call this cramped, it was cramped on her Specialized, but on that pink Cube with the ISM all the forward even more.
https://www.slowtwitch.com/Products/Tri_Bike_by_brand/Lucy_Charles-Barclay_s_New_Cube_8509.html

And if you compare this to her current 2023 Kona bike she has i think at least 50 mm more reach
https://www.slowtwitch.com/Features/Top_15_Women_s_Bikes_From_Kona_2023_8833.html

Jeroen

30

In your 2022 link, only Fenella and Haug look halfway OK. In 2023, LCB’s fit drastically changed for the better, Knibb looked good, and Haug remained good.

I do feel more women in 2024 will look like the top men did in 2023.

Jeroen, toss Funk into your list as well: https://forum.slowtwitch.com/...ost=8028174#p8028174

and Foley was also in a similar position at Indian Wells, and Sam is also in a similar position.

The question that has to be asked is, ‘why is the rule the rule?’

Is the rule the rule because it’s ideal, or because there are constraining factors such as bike geometry?

31

I do remember, I’m from that era in triathlon but your and mine cockpit positions were not even close to what we see now.
Look at the pictures from that era. And totally agree that you and I were riding that steep. I owned one of the first 80 degree seat angle bikes over here but my cockpit wasn’t that long and far forward.
Aerobars weren’t also that far angled up too and they are now so we need more reach.

Jeroen

32

Are the new generation of running shoes so good in cushioning while still being faster that quad muscles can be used more intense during the bike leg? It also seems that the bike times get faster, 4.00 to 4.05 are now possible for a lot of athletes. Does the positional change ask for a new tri bike geometry? More reach and more stack as well?
Are we on the edge of the need of a whole different design of tri bikes, will this create differences or new opportunities in aerodynamics, a different view of triathlon bike fit?

I think triathlon riders are riding steeper, not because it is better for running muscles, but because it is an overall better position for the power generation vs aero drag equation. Whether or not one runs after the ride.

But, as others have pointed out, UCI rules are also having a big effect on bike frame design. UCI rules are stifling innovation and if the UCI significantly loosened rider position rules for TTs, we would see big changes in rider position, and also in TT frame design.

If UCI rules allowed it, I think that riders would also ride somewhat steeper on road bikes, if frames were properly designed to accommodate steeper seat angles.

In the cases I meant UCI rules have nothing to do with it since a lot of these tri bikes are already UCI illegal.

Jeroen

Yes, but just because they aren’t beholden to UCI rules doesn’t mean they’re not influenced by UCI rules. I suspect this has a big impact on the geometries of tri-specific UCI illegal bikes. They still need to sell them to consumers, and a lot of consumers are riding a position based on a UCI-legal fitment. Hard to sell a new bike to someone when they need to change their position to ride it.

33

Are the new generation of running shoes so good in cushioning while still being faster that quad muscles can be used more intense during the bike leg? It also seems that the bike times get faster, 4.00 to 4.05 are now possible for a lot of athletes. Does the positional change ask for a new tri bike geometry? More reach and more stack as well?
Are we on the edge of the need of a whole different design of tri bikes, will this create differences or new opportunities in aerodynamics, a different view of triathlon bike fit?

I think triathlon riders are riding steeper, not because it is better for running muscles, but because it is an overall better position for the power generation vs aero drag equation. Whether or not one runs after the ride.

But, as others have pointed out, UCI rules are also having a big effect on bike frame design. UCI rules are stifling innovation and if the UCI significantly loosened rider position rules for TTs, we would see big changes in rider position, and also in TT frame design.

If UCI rules allowed it, I think that riders would also ride somewhat steeper on road bikes, if frames were properly designed to accommodate steeper seat angles.

In the cases I meant UCI rules have nothing to do with it since a lot of these tri bikes are already UCI illegal.

Jeroen

Yes, but just because they aren’t beholden to UCI rules doesn’t mean they’re not influenced by UCI rules. I suspect this has a big impact on the geometries of tri-specific UCI illegal bikes. They still need to sell them to consumers, and a lot of consumers are riding a position based on a UCI-legal fitment. Hard to sell a new bike to someone when they need to change their position to ride it.

Yes, exactly this.

34

Here is my fit on the P5.
I wanted the saddle much further forward but I’m maxed out in the cockpit. EX11 mount plate forward position, armpads almost as far forward as I found save to ride.
Sitting on the saddle at the back and clamp almost back at the seatpost. Everything further forward gave me a limited in reach at the cockpit.

To be clear, this is no attack on any brand because I see it and have it on all bikes even more when I put my saddle where I would like to have it so in the end i’m now extending my cockpit on the Cadex.

Jeroen

IMG_2065.jpeg

35

The question that has to be asked is, ‘why is the rule the rule?’

the rule is the rule in every endeavor where experts gather around a consensus way of doing things. if you find that 85% of top pole vaulters, or 92% of all formula one drivers, do something the same way, then it’s the rule. i didn’t make the rule. they made the rule. sometimes the rule is changed. it changed in cross country skiing, high jumping, shot putting and backstroke during my lifetime. when that happens, the rule changes. the athletes themselves changed the rule. it’s very rare that there’s 50 top athletes do something 30 different ways. there’s usually 1 way to do something important in an activity.

it may well be that the cockpit position will change, or will change for a certain number of people, or will change only when you use this kind of aerobar, and when that cockpit position changes then the rule will change.

36

I appreciate the conversation. Kahneman wrote at length about the philosophy of rules in his last book, Noise. I recommend it.

If the bike’s pad reach is confining the rider, you will see something that would otherwise not exist if the bike’s pad reach were longer. The observed consensus (what you’re labeling a “rule”) then is not an observation of choice but of a lack of option. New aerobars and extension plates are creating new options, and that is the reason LCB looks so drastically different in 2023 compared to 2022. It’s the reason why we’ll see a convergence of male pros in this position in 2024, and women hot on their’s and LCB’s heels. It’s the new rule.

I talk about why here: https://forum.slowtwitch.com/...ost=8024637#p8024637

I’ll sign off. I have saddles to ship.

37

The question that has to be asked is, ‘why is the rule the rule?’the rule is the rule in every endeavor where experts gather around a consensus way of doing things. if you find that 85% of top pole vaulters, or 92% of all formula one drivers, do something the same way, then it’s the rule. i didn’t make the rule. they made the rule. sometimes the rule is changed. it changed in cross country skiing, high jumping, shot putting and backstroke during my lifetime. when that happens, the rule changes. the athletes themselves changed the rule. it’s very rare that there’s 50 top athletes do something 30 different ways. there’s usually 1 way to do something important in an activity.

it may well be that the cockpit position will change, or will change for a certain number of people, or will change only when you use this kind of aerobar, and when that cockpit position changes then the rule will change.

This is an accurate observation, but it is interesting to read this from you (because I more remember your spirited essays about “elan” and french archers).

Because cycling and TT and triathlon bike positions were very stagnant. And then 35ish years ago, they weren’t. The rule changed (heck, you yourself were highly involved in this, and for the better), but, then and now, cycling is a sport that is very, very resistant to change. Bikes, frames, and molds are expensive and it is hard to justify new designs in a limited market. And in a market where big governing bodies fight change (usually with very little logic) tooth and nail.

To me it seems that riders are doing what they want (moving more forward), but bikes are not changing under them. Or changing very slowly.

38

Are the new generation of running shoes so good in cushioning while still being faster that quad muscles can be used more intense during the bike leg? It also seems that the bike times get faster, 4.00 to 4.05 are now possible for a lot of athletes. Does the positional change ask for a new tri bike geometry? More reach and more stack as well?
Are we on the edge of the need of a whole different design of tri bikes, will this create differences or new opportunities in aerodynamics, a different view of triathlon bike fit?

I think triathlon riders are riding steeper, not because it is better for running muscles, but because it is an overall better position for the power generation vs aero drag equation. Whether or not one runs after the ride.

But, as others have pointed out, UCI rules are also having a big effect on bike frame design. UCI rules are stifling innovation and if the UCI significantly loosened rider position rules for TTs, we would see big changes in rider position, and also in TT frame design.

If UCI rules allowed it, I think that riders would also ride somewhat steeper on road bikes, if frames were properly designed to accommodate steeper seat angles.

In the cases I meant UCI rules have nothing to do with it since a lot of these tri bikes are already UCI illegal.

Jeroen

Yes, but just because they aren’t beholden to UCI rules doesn’t mean they’re not influenced by UCI rules. I suspect this has a big impact on the geometries of tri-specific UCI illegal bikes. They still need to sell them to consumers, and a lot of consumers are riding a position based on a UCI-legal fitment. Hard to sell a new bike to someone when they need to change their position to ride it.

Yes, exactly this.

I’m not looking at the UCI rules when I fit customers unless they are specificly asking for it when they are racing TT’s. Otherwise there is no reason for it. I can’t wrap my head around why any brand would design a non-UCI illegal tri bike and still take those rules into their design……On the Trek SC, yes, but on a Cadex, Canyon Speedmax CF SLX/CFR, Cube Tri, etc, no

Jeroen

39

I’m not looking at the UCI rules when I fit customers unless they are specificly asking for it when they are racing TT’s. Otherwise there is no reason for it. I can’t wrap my head around why any brand would design a non-UCI illegal tri bike and still take those rules into their design……On the Trek SC, yes, but on a Cadex, Canyon Speedmax CF SLX/CFR, Cube Tri, etc, no

Of course you’re not looking at UCI rules when you fit customers. But nearly all the bikes you are fitting them on are dictated by, or influenced by, UCI position rules. Designers are influenced by many factors, but empirical evidence and max sustained power output are not usually high on the list. Especially when such evidence is very, very scarce.

40

I have to agree with the OP. I feel like I can never get my seat far enough forward. I think, ideally, I would like my seat to be almost directly over the crank centerline.