"The 33"-Road Bike Racing - Aerobars choice and placement on new TT bike

Hi all, I picked up a new Fuji D6 TT bike this week. I have spent a lot of time in the TT position over the years, actually have found it my most powerful position. However, my TT frame was a steel frame custom built in 1995, and is a more relaxed position, with about 74 degree seat tube angle, and not much drop between the saddle and the bar pads. I could stay in that position all day long and crank, I must say.

The D6 has a more aggressive position in both those regards. I have no problem with the lower drop, in fact, I am probably going to take a spacer or two out of the stack to get even lower, as my back is not perfectly flat yet. Clearly I am going to be doing a lot of dialing in over the next month or so.

I must say, I've been out of the TT position largely the last several years and mostly road riding. My speeds so far on the bike are only marginally faster than my road bike but I expect that will change as I get more power from training in the TT position. (caveat, first two rides were quite windy).

I'm looking for some feedback on the aero bars. The bike comes with stock Profile T2 alloy clip-ons, which are relatively straight. I find the initial set-up from the shop kind of narrow, and think my arm placement is constricting my lungs a bit being too close in. I find myself taking longer, deeper breaths as a result and working harder to do so. I even got a stitch in my side on longer hard efforts, and my mouth and throat get dry quickly. I widened the placement a bit, and its a bit less so, and not sure whether I should widen them more. Is this something I will grow into as I train in this position, or am I sapping myself on energy and oxygen uptake and should I widen them out until its not an issue?

My previous clip-on's on the older TT bike were Syntace C2, which I loved. They fit like a glove and the upward angle on the hand grips was so comfortable and stable I could stay on them all day, I was totally confident in the control, and I could even get out the saddle a bit with that grip for a little sprint or extra power when I needed it. The new Profile bars are less comfortable in the wrists, causing me to bend them forward and downward, and I am constantly repositioning my hands, not finding a sweet spot for very long. However, the good thing about the Profile are the for and aft adjustability, which the Syntace lack: I would have to change stems to accomplish that. Referring to a thread I found on slowtwitch.com, I found this interesting:

http://forum.slowtwitch.com/gforum.cgi?do=post_view_flat;post=2534603;page=1;sb=post_latest_reply;so=ASC;mh=-1;guest=124375696&t=search_engine (post #101)


Hey all,

Not sure when the data's from, but I figured I'd add a couple of points that might or might not be useful.

1. Upturned verus flat hand holds on aerobar basebars: We designed, built, and tested both for Saxo when making the Shiv. We tested at 0 and -15 degrees. The flat hand hold bar on the fully built bike (-tare) was 502 gF at 0 degrees and 389 gF at -15 degrees. The angled hand holds were worse by 7 gF at 0 degrees (509 gF) and better at -15 degrees by 21 gF (368 gF).

We since have finished an extensive study at A2 testing the same exact control bike over 6 months of testing -- full yaw sweeps of the exact same bike tested ~1 month apart at the same tunnel, same protocol. At 0 degrees, the data over 6 months is within 9 gF. At -15 degrees, the data is within 35 gF (more vortex shedding, component of side force load cell, etc -- we should expect data at yaw to be worse than 0 deg).

So -- TAKEAWAY -- same shape, design of basebar with only the upturn changing, the drag difference is almost immeasurable. So, we've gone with the upturned hand holds as you simply don't crash when going down hills/hitting bumps! Confidence in handling with aero performance is key.


2. Note that the tare values at A2 are about 180 to 150 to 180 gF across -25 to 0 to 25 degrees.

3. Kestrel's Cervelo data seems high to me but the trends seem to indicate the same wheels were used between the Kestrel and the Cervelo. I'd assume tares have not been subtracted. Looks like bar spec could be significantly different though. I'll wait to hear more because the data's confusing to me too.

Thought the bar stuff might be interesting though.

Cheers,

Mark
--
Mark Cote
MITAerobike (ST, Twitter)
Specialized Bicycle Components
Road Engineer/Aerodynamicist Any thoughts on whether I should switch to a bar like the Syntace with an upward bend, and if so, are there any that have fore and aft adjustment that you would recommend?


edit: adding product images:

http://www.pricepoint.com/images/styleImages/D_005%20SYESL7.jpg


http://s.wiggle.co.uk/images/profile%20t2%20plus.jpg

mods, I just copied and pasted this into the "before you start another TT thread..."

Your call if you want to delete this thread or keep it in its own discussion.

Most extensions that are clamped are spec'd to the same OD. I'd peek around Ebay to look for a bend that will work for you. Much less $$$ than buying new.

Unfortunately my Syntace are not oversize clamp or I could use them. Wondering if there is one with a similar bend that are adjustable fore and aft like to Profile T2. What's OD mean?

Outer Diameter - almost all extensions are 22.2mm

I've used that same set of Profile extensions, and no, they aren't perfect. Buy some extensions from Oval Concepts or Vision, or buy a bunch of different bends/styles from ebay - try them out, see what you like.
or, google search something like this: Google Shopping - Oval Concepts A700 Single Bend (http://www.google.com/products?q=oval+concepts+A700+single+bend&hl=en&aq=f)

Ahh, thanks for that, I should just get some extensions with more bend. I have an Oval Concepts road stem that I bought from Dr. Pete that I loved, stiffest stem I've ever had because it was slightly ovalized and tall, so I went with a shorter stem, but I liked the product a lot. But good Lord does their website suck!

Most extensions that are clamped are spec'd to the same OD. I'd peek around Ebay to look for a bend that will work for you. Much less $$$ than buying new.


Thanks for that. Any thoughts on the breathing issue and the width of the bars?

Thanks for that. Any thoughts on the breathing issue and the width of the bars?

No ideas without pics of shoulder shape, body size, stomach, etc.

No ideas without pics of shoulder shape, body size, stomach, etc. Well, in general terms, I had always read that arms too close in can constrict breathing. I never ran into that on aero bars until now. Or maybe I am just not well at the moment and don't realize it. But has anyone ever found their position too narrow and breathing constricted? Its a little peculiar, but I'll post a pic soon of the bar width. Maybe my extensions are too rearward and if I stretch forward it may alleviate. I do find me knees knocking the rear of the extensions when I am on the wings, standing up to get up to speed. I am 170 lbs., and 5 '11'' on a m/l D6 frame, which has a virtual top tube length of 55.5cm, although they call it a 56cm.

But has anyone ever found their position too narrow and breathing constricted?

I ride with my elbows touching. Could be the additional drop...

Interesting. I'll have to see if I acclimate. You could be right and it could be the additional weight up front and the additional drop.