The 123s are nice. I also like my Easton EC90 Track bars. I got them cheap and I really love the shape. The downsides are the price and the fact that after one crash they may be compromised. If I did wreck them, I'd consider steel if I couldn't get another pair cheaply.
If you can, try holding a few bars of bikes at your local track and see what feels right. Some are too narrow and some too wide. Some won't clear your forearms when holding the drops.
Pick the bars then get the appropriate stem (25.4, 26.0, or 31.6) so you don't have to deal with shims.
I have a Look Ergostem which is heavy, but awesome for dialing in my position. I also like Thomson X4 (4 bolt). I suggest this over the X2 (2 bolt) model if you are a sprinter type rider raging on the bars heavily. There are other great stems, but this is what I know of.
Also, if you are going to do standing starts, maybe stay away from regular (non heat treated) aluminum bars. I've heard of guys breaking them. Again, that depends on how strong you are.
Originally Posted by gtrob
Roadies can run tempo all year as that's what humans were designed for. If you want to be a cheetah, lay around and lick your paws more.