Seatpost setback and aerodynamics

[TomColnago]

Hi guys I'm looking to get into a more aggressive position on my bike. I sit quiet far back on my saddle and a lot of my club mates say I should be more on the rivet when in my aero position but this isn't comfortable for me. Would it be better for me to get a zero set back Seatpost so I can be closer to the front of the bike? Sort of like a adam hansen position?
Any comments would be appreciated
Current Seatpost is the stock colnago post with 25mm set back

[sawyer]

Hi guys I'm looking to get into a more aggressive position on my bike. I sit quiet far back on my saddle and a lot of my club mates say I should be more on the rivet when in my aero position but this isn't comfortable for me. Would it be better for me to get a zero set back Seatpost so I can be closer to the front of the bike? Sort of like a adam hansen position?
Any comments would be appreciated
Current Seatpost is the stock colnago post with 25mm set back

It's not clear that being further forward on your existing set-up will be less comfortable than a zero set-back post. If it's not comfortable for you then it will (a) be slower - over any reasonable distance (b) quite possibly injure you

What I suggest you do is get a bike fit. You're a classic candidate and vulnerable to mates' recommendations ...

[TomColnago]

Thanks for the quick reply. I have been fitted to this bike but as said I am trying to get more aero without sitting too far on the saddle as this cause problems with comfort. The idea was if I swap for a zero setback saddle i can have more free play with my saddle than having it shunted all the way forward on the rails

[Marin]

I don't think this works without aerobars and armrests. The further forward you sit, the less your legs can support your upper body because of decreased leverage, and your arms, shoulders and neck will be stressed more.

I'd work on getting your head and upper body as low as possible when leading the pack or riding solo, but I wouldn't mess up a good position for dubious aero gains. Even Tony Martin runs a setback post on his Vias, and he can go 48kph for 200k...

[Calnago]

Hmmm... Tough one without seeing you on the bike. Firstly, where did you get the info that the Colnago seatpost has a 25mm setback. It's 15mm as far as I know which is consistent with comparing it to a 3T Doric Ltd post (25mm offset) and say a Deda Superleggera (12mm). I'm really not a fan of zero setback posts on road bikes at all. And if you use one you should really have valid reasons for "needing" it on a proper road bike.
To get into a more aggressive position have you tried first both raising and moving the saddle forward both simultaneously. What this does is maintain your knee to spindle relationship while "pivoting" your entire position around the BB.
Just something to try. Since "a lot" of your club mates seem to suggest maybe a different position for you it's probably fair to say that something doesn't quite look right with your fit so perhaps a fit might be worthwhile for and additional eye.
But I'd hardly be looking at Adam Hansens fit as something to try to emulate. He's quite an outlier as far as fit goes.

[TomColnago]

Thanks for the replies guys. As you say it's hard to see what I'm trying to explain without a picture. I don't have much info on the colnago Seatpost but I saw online it was 25mm but I am probably wrong... my position is really comfortable on the hoods and drops but riding on theBay rivet is something I can't do for a long time so the thought was with a zero setback post I could sit further forward in an aero position on my hoods/drops without having to sit on the rivet.
Current fit details
Reach: 62cm
BB to saddle: 83.5cm

[Calnago]

If you're comfortable riding in the drops why do you feel it so necessary to be "on the rivet"?

[TomColnago]

If you're comfortable riding in the drops why do you feel it so necessary to be "on the rivet"?

My position isn't that aerodynamic which I am trying to improve and when testing positions out in the road the most aero seeming position with a flat back is when I'm on the rivet but I can't keep myself on the rivet due to pressure on the sensitive area as I'm a heavier rider (84kg) my thinking was if I can get the saddle further forward with a zero setback post I can get back into a comfy aero position not on the rivet but sat where I am happy with and compensate for the seat being further forward with a longer stem

[Marin]

I suspect you are not feeling the discomfort because your pelvis is shifting forward, but because it is rotating forward, so shifting the saddle won't help.

[Calnago]

Yes, I get what you're trying to achieve I think, just that in trying to achieve that you "may" be compromising your general all round riding position. But your call here. No harm in experimenting with different positions. I encourage it actually. Sometimes the only way to know what works is to learn what doesn't. Too many people will get a "fit" and then feel it's carved in stone. Good luck.

[sawyer]

Hi Tom
The first part of fitting is where you sit in relation to the BB - i.e. and then work out stem length, how low you can go etc. That position in relation to the BB is what you're proposing to change, and given you've had a fit, effectively what you're saying here is the fit is wrong.

That might be the case. And Calnago is right, no harm in experimenting. I'd say it might well be worth trying it, and perhaps having another fit once you've given it a go, talking it through with the fitter

[TomColnago]

Thanks guys I'll give it a go with a cheap Seatpost and if it works then get a deda superleggera with zero setback

[tarmackev]

Hi Tom
The first part of fitting is where you sit in relation to the BB - i.e. and then work out stem length, how low you can go etc. That position in relation to the BB is what you're proposing to change, and given you've had a fit, effectively what you're saying here is the fit is wrong.

That might be the case. And Calnago is right, no harm in experimenting. I'd say it might well be worth trying it, and perhaps having another fit once you've given it a go, talking it through with the fitter

As above
Also as you slide the saddle forward you have to raise it to keep the distance from the BB the same, this increases your frontal area, even with a flat back on the drops your not really any more aero.
There awesome incredibly fast guys who aren't aero, especially bigger guys like yourself.

There is however nothing wrong with experimenting.


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[defride]

As others have mentioned that position relative to the BB is critical. I'd moved more forward over the BB when changing to a new frame. After spending time on the new bike I found I was riding on my quads excessively and burning them out earlier than I thought I should when pushing on the hills. I'm fitter than ever and the new frame is much stiffer and lighter so I've been going quicker hence I'd not really seen it as a problem initially. However, dropping back onto the winter bike I noticed I was getting much better leg extension on the climbs so switched to a setback post i had knocking around and I'm no longer burning out those quads on the new bike. Fortunately the extra length to the bars hasn't been a problem.

[AJS914]

I don't understand the theory in play here. How would moving the saddle forward 25mm, for example, make you more aero?