Do we need a new tri bike geometry?

There seem to be a continuous stream of pro athletes riding super steep seat angles. Up until now more man then women, but if we look at the positions of Sam Laidlow, Daniel Baekkegard to name a few but there are much more we see saddle clamps max forward on the seatpost and the saddle very far forward on the rails and still sitting on the front of the saddle. So that corresponds to virtual seat angles of 84 to 88 degrees or more.

These athletes in almost all cases lack reach in their cockpits, both Laidlow and Baekkegard ride their Canyon’s with angles extended spacers to get more reach. And also add stack.
I see this as well with a lot of other athletes on different brands of bikes like Argon18, Cadex, Felt, Cervelo which is not strange since they share the geometry quite a bit.

These positions are much more quad use orientated then with the saddle further back. Is this to ‘save’ those glutes, hamstrings and calves for the run? Are they now able to ride so steep due to the carbon running shoes that allow the quads to be ‘over’used during the bike?
I still remember Laidlow cramping during one of the PTO races last year as well as Blummenfelt on several occasions.
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?

Jeroen

I think so. A tt bike with a 75-76 degree geometry seems like a no-go for the bike positions that most of us are riding. When you see Anne Haugs bike for example, I can’t help but think there is some saddle flex that translates into a bit of energy loss. An 82-84 geometry frame would allow the saddle to sit a bit more centered on the seat post and tube.

I think so. A tt bike with a 75-76 degree geometry seems like a no-go for the bike positions that most of us are riding. When you see Anne Haugs bike for example, I can’t help but think there is some saddle flex that translates into a bit of energy loss. An 82-84 geometry frame would allow the saddle to sit a bit more centered on the seat post and tube.

We are not talking about bikes with 75-76 degrees, we are talking about bikes already with at least 78-81 seat angles and still these pro’s are riding maxed out forward positions so end up in virtual seat angles of almost or at 88-90 degrees.

Jeroen

Move the seat forward. Move the handlebars forward and down. You’ve taken your exact same position and rotated it around the bottom bracket. You are now lower and likely more aero at the expense of a fraction more weight on your arms.

Yes, it would be very nice if tri bikes had a longer reach and steeper seat angles. IMO the UCI 5 cm saddle setback rule has ingrained a standard position to such effect that even tri bikes are largely built around that rule.

Agree with your comment about UCI- legality, and that leads to investment from the designers/fabricators on the ‘slacker’ 78 seatpost.

However, if you do go steeper and rotate then you are also moving the weight forward so there is more on the front wheel and less on the back which is going to be more of an issue for the ‘mass market’ buyers. TT bikes are niche sales in any case compared to pretty much any other form of bike (aside from bike polo, etc), and so separate out UCI legal TT and triathletes into separate R&D paths / revenue streams does not make commercial sense.

another issue with rotating the position is being able to see the road ahead. My limiter on getting lower is my neck; if I get my shoulders any lower I won’t be able to see the road ahead.

I think so. A tt bike with a 75-76 degree geometry seems like a no-go for the bike positions that most of us are riding. When you see Anne Haugs bike for example, I can’t help but think there is some saddle flex that translates into a bit of energy loss. An 82-84 geometry frame would allow the saddle to sit a bit more centered on the seat post and tube.

We are not talking about bikes with 75-76 degrees, we are talking about bikes already with at least 78-81 seat angles and still these pro’s are riding maxed out forward positions so end up in virtual seat angles of almost or at 88-90 degrees.

Jeroen

Huh? …what a weird response.

Not sure I understand the logic of your response dude…“we are not talking about…” maybe you aren’t but the fact that the new P5 was designed with a very relaxed geometry hence why I chose it as an example.

Did you read my last sentence? 82-84 is steeper than 78-81…so aren’t we saying the same thing?

I think so. A tt bike with a 75-76 degree geometry seems like a no-go for the bike positions that most of us are riding. When you see Anne Haugs bike for example, I can’t help but think there is some saddle flex that translates into a bit of energy loss. An 82-84 geometry frame would allow the saddle to sit a bit more centered on the seat post and tube.

We are not talking about bikes with 75-76 degrees, we are talking about bikes already with at least 78-81 seat angles and still these pro’s are riding maxed out forward positions so end up in virtual seat angles of almost or at 88-90 degrees.

Jeroen

Huh? …what a weird response.

Not sure I understand the logic of your response dude…“we are not talking about…” maybe you aren’t but the fact that the new P5 was designed with a very relaxed geometry hence why I chose it as an example.

Did you read my last sentence? 82-84 is steeper than 78-81…so aren’t we saying the same thing?

It is in no way meant as an offence reaction so keep your cool :wink:
What I meant is that we are already talking about bikes as in case of the Canyon’s that are already built on a 80 degree seat angle and still these athletes push their saddles onthe rails and on the seatpost all the wat forward. So that is so much more as when it was a bike with a 75-76 angle and push your saddle forward.

Jeroen

Move the seat forward. Move the handlebars forward and down. You’ve taken your exact same position and rotated it around the bottom bracket. You are now lower and likely more aero at the expense of a fraction more weight on your arms.

Yes, it would be very nice if tri bikes had a longer reach and steeper seat angles. IMO the UCI 5 cm saddle setback rule has ingrained a standard position to such effect that even tri bikes are largely built around that rule.

But that is not what they do, they do push saddle and cockpit much further forward, but not down. I would even say slightly more up instead of down. That’s why my original post was more reach and more stack :wink:

Jeroen

Move the seat forward. Move the handlebars forward and down. You’ve taken your exact same position and rotated it around the bottom bracket. You are now lower and likely more aero at the expense of a fraction more weight on your arms.

Yes, it would be very nice if tri bikes had a longer reach and steeper seat angles. IMO the UCI 5 cm saddle setback rule has ingrained a standard position to such effect that even tri bikes are largely built around that rule.

But that is not what they do, they do push saddle and cockpit much further forward, but not down. I would even say slightly more up instead of down. That’s why my original post was more reach and more stack :wink:

Jeroen

Yeah that’s very fair and correct. The pros won’t move the bars down because they’re basically as low as they need to be in terms of aero. For the average rider there’s usually a fair but of saving to be had by getting lower.

Def want more reach and steeper seat angles, but I wouldn’t add stack to the bikes simply because it makes them more limited. I don’t see a huge issue with the current setup of airfoil spacers to raise the pads if needed. You can always adjust up but there’s a hard stop on his low the pads can go.

There seem to be a continuous stream of pro athletes riding super steep seat angles. Up until now more man then women, but if we look at the positions of Sam Laidlow, Daniel Baekkegard to name a few but there are much more we see saddle clamps max forward on the seatpost and the saddle very far forward on the rails and still sitting on the front of the saddle. So that corresponds to virtual seat angles of 84 to 88 degrees or more.

These athletes in almost all cases lack reach in their cockpits, both Laidlow and Baekkegard ride their Canyon’s with angles extended spacers to get more reach. And also add stack.
I see this as well with a lot of other athletes on different brands of bikes like Argon18, Cadex, Felt, Cervelo which is not strange since they share the geometry quite a bit.

These positions are much more quad use orientated then with the saddle further back. Is this to ‘save’ those glutes, hamstrings and calves for the run? Are they now able to ride so steep due to the carbon running shoes that allow the quads to be ‘over’used during the bike?
I still remember Laidlow cramping during one of the PTO races last year as well as Blummenfelt on several occasions.
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?

Jeroen
i think we need more reach and maybe we need the old school stem back.

Not enough FC (front-center) has been the largest problem in my view for about 8-12 years depending on the brand. Seat angles of 80-84 work much better/stable if you have some wiggle room there.

ETA: I wonder what a 51 P5 disc would look like with a 48 fork in it? or are the forks exactly the same but the achieve relative greater FC in the 48 by virtue of a 71 vs 72.5 head tube?

Maurice

I think so. A tt bike with a 75-76 degree geometry seems like a no-go for the bike positions that most of us are riding. When you see Anne Haugs bike for example, I can’t help but think there is some saddle flex that translates into a bit of energy loss. An 82-84 geometry frame would allow the saddle to sit a bit more centered on the seat post and tube.

i don’t see any modern, current, relevant tri bikes with 76° seat angles. but i’ll grant you seat angles are harder to quantify now. it doesn’t matter how the seat tube gets from the BB to the seat post clamp. all that went out the window just after the turn of the century, with the curved seat tube on the P3. what matters are:

  1. what the stack and reach of the frame is;
  2. what the front center is;
  3. what the steering geometry is.

those will determine how the bike will fit and handle as long as the seat post hardware allow for a lot of fore/aft movement. and most of today’s bikes have that. you’re always going to need this because of the difference in how people sit saddles. if you measure seat angle using the BB and the seat post clamp as the measuring points, and you nose ride an ISM, you could be riding a 76° bike with that saddle and an 80° bike with a gebiomized, with your hips in the same place on both saddles. this is why stack/reach, FC and steering geometry are the ways you’ll know how a bike will handle. seat angle is a less relevant measure now.

but i think bike designers are not focusing on the major issues. what is the future of tribike transport or a service like it? if that goes away it’s you and your bike on an airplane and a lot of today’s tri bikes are virtually unable to be placed in a typical bike case (that is hard sided and can be taken as checked baggage without a fee). if i was making bikes today i’d make them with full forearm rests, but still collapsable easily into a bike case. the problem with this market (meaning, the consumers) is that it’s seduced by meaningless metrics and makes bad purchase choices based on them. i don’t see anything wrong with today’s geometries and i’m suspicious that the longer cockpits of a few pros are going to necessitate tri bike frames made with the longer front centers that would best accommodate them. way bigger fish to fry if you’re a tri bike product manager.

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

Jeroen

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.

The pro’s I help fit would benefit from frames with longer reach and higher stack. Sizing up is easy except when it’s a small woman and that limits how low a seatpost will go, or when it’s a man already on the company’s largest frame size.

wrote about it here: https://forum.slowtwitch.com/forum/Slowtwitch_Forums_C1/Triathlon_Forum_F1/Tri_Bikes_need_greater_Pad_Reach/X_and_the_role_of_Crank_Length_in_bike_fits_P8024637/?search_string=milesthedog#p8024637

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

Example: https://www.instagram.com/reel/C0VeKYWigkF/?igshid=N2ViNmM2MDRjNw==
.

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.

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.