Lots to think about.

I've never done it, but it is my understanding that you can mount traditional STI shifters on the ends of a bullhorn base bar. It was actually pretty common practice until just a few years ago. But in my opinion, why would you want to do that? You would get a slight reduction in frontal profile, which is one of the major reasons for cowhorn base bars in the first place, but not nearly as much as bullhorn bars with aero-style brake levers, so at that point you may as well keep your drops.

I'm a big fan of clip on aerobars with a standard road base bar and have talked about the merits of this setup on here before. As far as I'm concerned, a dedicated TT/Tri cockpit is for a dedicated TT/Tri bike.

I recently switched the extensions on my Profile Design "AirStryke" bar to "S-Bends." I've been meaning to make a post on the conversion, but just haven't had time. The original extensions were the standard, upturning, kooky diamond shaped thing that many people associate with the very word "aerobar." They were pretty comfy, but not aggressive enough for me. I am still using the same pads but put S-Bend extensions in. (Though my S-Bends are actually made from a mountain bike handlebar cut in half!) I can ABSOLUTELY generate a lot more power with that position, and I'm not a huge gear masher - in fact I have a triple and almost never use my big ring - I'd rather spin at 120. Yesterday I was riding hills and while I don't climb in my aerobars much, there is one point where I come down a descent at 40mph and then have a short rise before I descend again. I stay tucked and when I hit that rise I just lever hard on the bars, put down 400-500 watts, and keep my speed from ever dropping below 30, which I was never able to do as efficiently with my old bar.

In my particular case, I put a lot of effort into making sure my S-Bends WOULD be comfortable. For me it's almost more of a pistol grip than a flat bar, which I think is the perfect compromise. I tried out a few aero bars down in Solvang for the ToC time trial recently and did find that most "S-Bend" style bars were quite uncomfortable. The big problem for me was that S-Bends in clip on's frequently don't have enough rise, so your forearms are angled way down and your wrists and in a very awkward position. This is less of an issue with an integrated aero bar with S-Bends, but since everyone wants the S-Bend style on their road bikes (Of course most people want it just because that's what they see the pros ride...) there are plenty of manufacturers who are making S-Bend based clip ons regardless of how optimized they really are.

My advice - don't be afraid to try several things to get what you actually like. If you have a really well stocked LBS you can probably fiddle with a few options. I got really lucky being able to see a half dozen vendors at the Tour of California (Including Oval Concepts, who I was about to buy a bar from until I tried it out and realized it wasn't quite right).

Final thoughts - not sure how good you are with general bike geometry and whatnot, but don't forget that putting clip ons onto a road bike will require you to move your seat forward and up, to the point that many people (myself included) say a non-setback or forward pitched seatpost is mandatory.

Those are some freaky weird extensions

Heh, that's probably true.

Of course I think I'm about as likely to mistake that bike for a jet fighter. That's got to be one of the meanest looking bikes around.

Thank you everyone, especially to JamieM and GGehrke for taking the time to make such extensive comments. In light of what you both said, I will go the route of "S" shaped clip-on bars. Clip-ons also have the obvious benefit of being easily removable for those times that I want to do a group ride with the old paceline crowd (the guys with whom I used to ride would not look too favorably on even the mere presence of aerobars, as they ride a VERY disciplined paceline). Way back in the late 80s (when I raced my last triathlon), I had an integrated Profile aero/cowhorn setup, so I think that I should be able to get comfortable again fairly quickly riding laid out in the aero position.

I've got a long way to come back. This summer I wanted to run a trail ultra and really hurt my knees with the long runs (especially the mountain downhills). I sat out most of the fall, trying not to face the inevitability of surgery, and lost a good chunk of my cardio conditioning (and putting on more than a couple of pounds). Now I'm doing rehab from arthroscopy and that's what's gotten me back into the pool. I find triathlon a bit frustrating, as I have a wife and child I have only so many hours for training (so I'm going to suck at three sports, instead of being mediocre in one). However, returning to this sport will allow me to spread the stress from training over three sports (and my ever more fragile aging body will appreciate that). The point of all this is to again say thank you to those who were willing to spend so much time helping a novice and a stranger.

Dave

One solution that I've been looking at and still want to get very soon is the Oval Concepts A711 modular aerobar 'system.' Instead of clipping the aerobars onto the handlebar, they have a special front cap for the stem that has the mounts for the pads and extensions. Because it's compatible with their standard stems, if you want to take it off you can replace it with the standard front cap and boom - aerobars gone. I hate taking my clip ons off, so this is much easier.

When I was at the Tour of California I spoke very extensively with the Oval Concepts rep who had their stuff on display at the Chipotle/Slipstream/Felt tent. They announced the system early last fall, but it is just now actually starting to be in stock at QBP (their distributor - ALL bike shops can order from QBP). Some parts actually still aren't, but should be by the end of the month.

The one thing I didn't like about their system was that I felt the S-Bends didn't have enough rise, but the benefit of it being "modular" is that if you want to use a different brand or come up with some homebrew solution, you can go that route and save some money. I plan to pick up their stem/front cap only and re-use my current extensions and hopefully armrest pads (The profile F-19 pads I have are very comfy).

They even have an A930 "Aero Top Cap"
http://82.195.150.45/Models.aspx?ModelID=24308
Looks like a total gimmick, but honestly I'm TOTALLY picking one up (in a month when it's available)

Anyways, I am very impressed with their product, which is why I bothered to rave about it :P Check them out at http://www.OvalConcepts.com and look at the A711 and A911 systems (difference being that A711 parts are aluminum and A911 are carbon - but you can mix and match). The closest thing to a review I've seen is here: http://www.slowtwitch.com/mainheadings/techctr/shorty2.html
The rep in Solvang said they haven't sent them out to the magazines to be reviewed because they didn't want reviews being published before all the parts were actually available.

For almost any riding conditions, I would say that the potential advantage of aerobars quite outweighs any considerations of weight. First, let me say that, manufacturer's claims to the contrary, weight really is not that big of a consideration for most riding. That is, unlike running, there is no vertical component to riding a bike. Thus, on level ground, weight is almost immaterial and it is drag from air resistance that limits your speed. On flat ground, added weight is principally felt in reducing your ability to accelerate (inertia). Now, in the mountains, weight is a much bigger factor. In fact, many (most?) pro cyclists ride regular bars for mountain time trials, as they need the hand positions of regular bars for climbing. So, if you're riding in the Rockies, then ditch the aero bars. However, if you're riding primarily on flat or rolling terrain, I think that the aerodynamic gains from clip-ons far outweighs any considerations of weight (and, of course, the faster you ride the more benefit one gets from aeorbars). I hope that this helps.

Dave

I say absolutely. Aerodynamic advantage over drops position is not huge. Though I do say that somewhat reluctantly because I recently experienced the benefit of narrowing my aerobars and getting a benefit in speed, so getting your arms and shoulders as narrow as possible really does help a lot. However, wind tunnel testing shows that the effect of air flowing "through" a person is pretty significant as well, which the drops position does provide.

What is huge, though, especially for triathletes, is having the ability to hold it comfortably. Aero bars provide skeletal support, so you're not using your muscles to hold up your torso - it's just sort of chilling. Drops (at least for me) is a very tiring position because you are holding yourself up primarily with your triceps and lower back muscles, especially when you are trying to be aerodynamic in that position. Remember that a proper "drops" position has bent elbows where your hands can reach the brake/shift levers.

I do, however, like keeping the drops position in case you need it, which is why I so strongly advocate the road-bar/clip-on combo. I mostly only use my drops for descending because you're mostly aero and still get good leverage on the brake levers.

Road bike in the velodrome? I wouldn't think they'd allow that...

But I love hearing results from the track because they take out so many of the variables of normal road riding. I'm thinking of asking my LBS to "test drive" an aero helmet and doing some coast down tests with it on a hill to decide if I should buy it, but a velodrome test would really be the best.