TT Position vs. Triathlon Position

pauly a said:

I'm trying to figure out whether or not I want to make my current road bike and try and make some modifications to it in order to make it more aero, or whether I should drop the money on purchasing a dedicated TT/tri-bike for next year. I want the bike to be suitable for riding both TT's and tri's. My question on the whole issue is the difference in positioning between the two. I've read that the triathlon bike has a steeper seat tube angle so that it saves the legs better for the run portion, but I'm not sure whether or not a steeper seat tube angle is used for TT's. So my question - is the steep seat tube angle appropriate for TT?

you mean a lay back seat post for triathlon, to try enforce glute and hamstring use opposed to quad muscle groups.

cambriabike.comseatpost.htmOpen ↗

pauly a said:

I'm trying to figure out whether or not I want to make my current road bike and try and make some modifications to it in order to make it more aero, or whether I should drop the money on purchasing a dedicated TT/tri-bike for next year. I want the bike to be suitable for riding both TT's and tri's. My question on the whole issue is the difference in positioning between the two. I've read that the triathlon bike has a steeper seat tube angle so that it saves the legs better for the run portion, but I'm not sure whether or not a steeper seat tube angle is used for TT's. So my question - is the steep seat tube angle appropriate for TT?

if you use your road bike, you may want to use a setback post turned so it moves your seat more forward.

that said, some tt/tri bikes have steep seat tube angles (76+), and some don't. the trek tt bike, for example, has a seat tube angle of 74 (the last time I looked) which is in line with a road bike. pro riders especially want to maintain the same st angle. I, on the other hand, like a steep angle and my tt bike is set up between 79 and 80 as best I can measure. and I am not a triathlete (but do have a running background - maybe that's why I like it). most roadies I know have their tt bikes set up a little steeper, but most are not as extreme as mine. if uscf ever starts enforcing uci rules, I will have to make a major adjustment because the nose of my saddle is too far forward.

try different setups to see what works for you.

rv said:

if you use your road bike, you may want to use a setback post turned so it moves your seat more forward.

that said, some tt/tri bikes have steep seat tube angles (76+), and some don't. the trek tt bike, for example, has a seat tube angle of 74 (the last time I looked) which is in line with a road bike. pro riders especially want to maintain the same st angle. I, on the other hand, like a steep angle and my tt bike is set up between 79 and 80 as best I can measure. and I am not a triathlete (but do have a running background - maybe that's why I like it). most roadies I know have their tt bikes set up a little steeper, but most are not as extreme as mine. if uscf ever starts enforcing uci rules, I will have to make a major adjustment because the nose of my saddle is too far forward.

try different setups to see what works for you.

they have haven't they! nose of seat? 5cm behind the bottom bracket, or does that only apply to track racing. "lay it back."

you'll find that you can apply a little more presure, and you won't feel to uncomfortable.

closesupport said:

you mean a lay back seat post for triathlon, to try enforce glute and hamstring use opposed to quad muscle groups.

cambriabike.comseatpost.htmOpen ↗

I think you have it reversed -- you want to use your quads on the bike, because you use hips/glutes/hammies more on the run. Tri bikes got steeper tubes over the years, and now many of the pros are heading back toward road angles (but most still ride steeper than 73 degrees). Check out the various articles in slowtwitch.com.

As for the diff between tri and TT... I don't know. I'd find what allows you the best overall speed (i.e., tradeoff of losing power as you move steeper vs. gain in aero as you go steeper). Somewhere is your sweet spot.

[quote="Aztec"]I think you have it reversed -- you want to use your quads on the bike, because you use hips/glutes/hammies more on the run. Tri bikes got steeper tubes over the years, and now many of the pros are heading back toward road angles (but most still ride steeper than 73 degrees). Check out the various articles in slowtwitch.com.


yep.. I think your right . ..
I am currently going through this process myself. I just purchassed a 0 setback seatpost (which basically gives 1-2 deg when centered) compared to a 2.5 cm setback centered saddle, my 74 deg will then become a 75-76 depending how forward I'll ajust it ..and will get an integrated front piece (cinelli angel) because I just can't get low enough with clip-ons.
http://www.slowtwitch.com/mainheadings/techctr/bikefit.html#Anchor-47857

Aztec said:

I think you have it reversed -- you want to use your quads on the bike, because you use hips/glutes/hammies more on the run. Tri bikes got steeper tubes over the years, and now many of the pros are heading back toward road angles (but most still ride steeper than 73 degrees). Check out the various articles in slowtwitch.com.

As for the diff between tri and TT... I don't know. I'd find what allows you the best overall speed (i.e., tradeoff of losing power as you move steeper vs. gain in aero as you go steeper). Somewhere is your sweet spot.

maybe your right! but TT i believe to be more fitting when i'm sat further back and am able to generate alot more power, plus i have the option of sliding forwards to give that muscle group a rest without stopping.