For various reasons, I'm contemplating switching out my riser bar for some bull horns.
-Do you like to mount the brake levers inline (a la CX style) or hang them off the horns (TT style)?
-Do you find yourself spending more time with your hands on the 'horns' or on the flat section?
-If you converted to bull horns, did you find that you needed to get a new stem to attain a proper fit for you?

I know it's pretty much a personal preference thing, but I thought that there might be a consensus out there...

NOTE: I added the word "handlebar" to the thread title. It is reflected in the OP title, but is not on the main index page. Sorry for any confusion.

i converted my old MTB from flat bar to bullhorns. the bike was since wrecked in a crash, but i can answer your questions.




-Do you like to mount the brake levers inline (a la CX style) or hang them off the horns (TT style)?

i put reverse pull levers out on the horns TT-style. keep in mind that levers designed for flat bars won't fit on most bullhorns (different diameters).





-Do you find yourself spending more time with your hands on the 'horns' or on the flat section?

my hands were on the horns the VAST majority of the time. that's why i went with reverse pull levers, so my hands would be close to the levers.





-If you converted to bull horns, did you find that you needed to get a new stem to attain a proper fit for you?

i did need to get a shorter stem to get the fit right with bullhorns.




here are some pics of my bullhorn conversion (RIP buddy, i miss you):

Steely, this you direct experience with what I'm thinking about doing, let me ask another pointed question (that's probably answered in that second pic, but my legally blind self ain't seeing it): What about shifters? Did you use stem shifters (that are prolly blending in with the tape in that pic)?

I've got bullhorns on one of my roadbikes and really like them. For some reason it makes the bike more fun to ride. I've got TT brakes mounted at the ends of the bars, and I've got downtube shifters on my frame. My hands are on the horns about half the time and on the tops about half. The horns are better if you going faster or riding in windy conditions. I didn't change my stem length. BTW, I made my bullhorns from some old handlebars by just cutting off the drops.

I have bullhorns on an old Schwinn I converted to fixed gear, and my one brake lever is inline.



My hands are on the flats, the horns and at the bend (about where hoods would be on a drop bar) depending on circumstances. That is, if I need to get low, I'll reach out toward the end of the horns; if I feel I might need to get to the brake quickly, I stay on the flats near the brake lever. Most of the time my hands are at the bend.

Of course, riding fg, I don't use the brake much, so I suppose where I kept my hands might be different on a geared bike.

I didn't change the stem.

You could get some cross/interrupter levers to put the brakes on the tops, too, so you wouldn't have to choose one over the other.

Adding on -- when I went from a flat bar to drops (honestly, since I ride on the hoods 90% of the time with this bike, they might as well be bullhorns ), I got a shorter stem.

Just recently swapped out the drops for horns. I run them with the CX levers - when I'm riding in traffic where I am braking a lot I'm on the tops of the bars. I like the look of the TT levers, but for me it just wasn't the right area to put my levers.
I'd say I switch between the tops and the horns equally - when I have long stretches where I can just cruise I'll be on the horns, when I'm going from light to light and in traffic I'm on the flats.
I currently have a stem shifter, but want to put bar end shifters on eventually. I think that'll be my perfect set-up - CX brake levers, bar end shifters, on a bullhorn.
Here's what I commute on:

i like TT style brakes

I had inline brakes but really wanted the TT style because i ended up spending way more time in the horns

if you look closely at the second pic i posted, you'll see that i had a set of low end shimano shifters on the bullhorns. now, the diameter of the bullhorn bars was too big for the shifters, so i used a dowel rod to stretch out the hanger bracket on the shifters so that they would fit onto the bullhorns. it took a little elbow grease, and some slightly longer bolts, but in the end it all worker, even if it wasn't the most elegant solution.

in subsequent research i have learned that there are some companies out there that make bullhorns with a 22.2mm MTB diameter instead of the more typical 23.8mm road diameter. if you can find one of those, it would be possible to attach flat bar brake levers and shifters.

I switched flat bars to bullhorns, and I kept my brakes inline CX style just for ease of conversion. I did also get a slightly shorter stem to accomodate the extra reach out the horns.

I find that I still ride on the flats most of the time, but it's nice to have the option of another hand position. Usually, when I'm starting from a standstill, climbing, or mashing out of the saddle, I'm out on the horns. It helps me get a little extra leverage than the flats. But as soon as I'm up to speed and back down in the saddle, I'm back on the flat, so that's where I keep my brakes.

Two considerations to keep in mind: 1) you might need brake lever shims. My flat bar had a 31.8 clamp, whereas the bullhorns are 26.0, so I had to get shims in order for the brakes to snug down tight enough. 2) you might run out of cockpit space. With my flat bar, I had plenty of room for a reflector and two headlights on the bars--now I don't have any, so I had to move the headlights up to my helment and backpack strap.