Triathlon - Adjusting Bike Seat and Stem

I am researching different options on carbon components to more aero on my tri bike! I am look for a flat forward seat post and a 70mm stem...I am stretched out on my bike...perhaps getting an adjustable stem.

Any ideas on what I should buy?

Carbon components will not be more aero than similarly-shaped alloy components. Lighter, possibly. More expensive, definitely. But not more aero.

Do you mean a FAST forward seatpost - to get your effective seat tube angle on a road bike steeper? If so, there are a few options.

Same with the stem. Lots of options. Although, if you need a 70mm stem with a forward post and your saddle slid forward, I would have to suspect that your bike is too large for you.

The main advantage of an adjustable stem is to allow you to get lower in front (after you've removed all spacers, etc.) It's gonna be tough to find a 70mm adjustable stem, though.

Did that help at all?

I tried to look at the pic in your avatar, but can't make anything out because it's so small. Sorry.

Steve

Hi Steve,

You are right the adjustable stems are 80mm-longer. I want to be both aero and light...the reality is how much would I invest into carbon. I have a Lightspeed and yes its too long for me! I am going to the local bike shop this weekend to see what they suggest for a seatpost...I will probably get a cheap 70mm stem.

Thanks for your input!

Cheers,

Mari

Good luck in your search. Are you getting a fitting or just looking for a seatpost?

FWIW, I wouldn't lose much (actually, any) sleep over the weight difference between a carbon stem and an alloy stem. Triathlons (in general) are relatively flat. Weight makes the most difference in sustained climbing efforts. Even then, the biggest differences are made in rotational weight, not static weight. Besides, the weight difference in a stem is only going to be a few grams. Carry one less CO2 shot in your saddlebag and you're more than covered.

If I had a better (larger) picture of you in your riding position, I could be more help. It's tough to make anything out in your avatar. What I can tell is that you're pretty high in front and that you're not supporting your weight with your skeletal muscles.

The first issue could be partly resolved by removing spacers (if there are any installed) and/or "flipping" your stem. On a road frame that's too large, though, it's going to be tough to get truly low in front.

The forward post and sliding the saddle forward will help with the second issue. Although, you'll probably still end up needing a shorter stem, as you're pretty stretched out.

It's a little old, but this is a good article on fitting for triathlon and explains the dynamics that happen between a road bike fit and a tri bike fit.

http://www.slowtwitch.com/mainheadings/techctr/bikefit.html

Steve

Hi Steve.

Thanks for the input on the carbon vs alloy...so much money goes into this sport...its insane! lol

I have no spacers and unable to flip stem. I have the smallest tri-bars too. So like you mentioned sliding the saddle forward will bring me closer and a shorter stem.

The article is so extensive. Ultimately, I am looking for a 90 degree angle on my arm position on the aero position.

Mari

mari,

keep in mind that as you decrease stem length, you might sacrifice bike control. smaller movements will possibly resut in twitchy oversteering, especially when stretched out over the aero bars.

something to consider :)