I was having that problem myself, on a whim I bought a small Arkel handlebar bag (http://www.panniers.com), and figured I'd make it work some how. I was happy to find out that the mounts for the Arkel bag are of an 'open' design and I was able to thread the cables from my b-levers throught he mounts. I had to re-do the brakes in the process but that didnt take more than 10 minutes. For the setup on this bike, the bag is tilted slightly forward, not much.
The speedometer fits on the bar as well, and there is still room for one more gadget. If the speedometer doesnt fit, another option is something called a 'Space Grip' found on: http://www.minoura.jp/acc-e.html
This device wont support a handbar bag, but it will support all your other gadgets. Also, alot of handbar bags block head lights, the 'Space Grip' can place them higher.
I'll post pictures in a couple of days of my handlebar bag setup.
the ever shifting stable loaded with comfortable road bikes and city and winter bikes
If you have to, just cut some of the handlebar tape and move the computer mount outboard. Most handlebar bag mounts are designed to be installed after the brake levers are on the handlebars! The trouble is in trying to get a handlebar mounted light to shine around or above the bag... computer, no problem. Buy a Jandd, or a Ortleib, or even an Avenir, and I'll bet you can fit it without removing your brakes.
..The trouble is in trying to get a handlebar mounted light to shine around or above the bag... computer, no problem...
-For this workaround, one can mount lights to the front brake bolt (with a bracket), to a rackless fork (special bracket, crono metro nob), and to a front rack directly(either on the hoop or at the platform front).
I've found that the Minorra "space grip" accessorie bars are not very usefull in combination with a handle bar bag for me. Although one might be mounted, they tend to make it inconvenient to open the bag (while on the bike)-and I tend to grab stuff all day. Nitto makes a lower profile version that I've had some luck with (its Nitto-so its crazy expensive).
Topeak makes what is known as a Tour Leader's handlebar bag, in two configurations, IIRC. I have one for my touring/rando bike. It is narrow enough not to interfere with the brifter shifting, and the bar mount goes either side of the stem, leaving plenty of room for a computer OR it has a removable mini-bar of its own on the mounting hardware that can be used (if you don't use, just toss it).
The bag has reasonable space in the main compartment, a top section for documents, a clear plastic map holder than velcros on, zip-up side pockets, a top carry strap and a shoulder strap, and a decent-sized front pocket. Phew!
I like it, although I have modified it slightly to lower its height on the bars (don't ask -- it's more complicated that it seems).
I use the Topeak bag -- the smaller of the two. Nice bracket to clip out, comes with a fanny pack strap and rain cover, and the computer mounting bracket which i do use. the bag is not that big... better for day rides. I decided to save money and go small... cause big means... i take MORE stuff. Happy so far.
On sale for about 30 bucks