Any company that sold a bike with head tube cable stops owes their customers each a new frame if the old one can't be reconfigured to put the stops on the down tube or top tube where they will actually work.
I spent hours last night trying to figure out cable routing on a Serotta Legend Ti that wouldn't destroy the cable housing within weeks. The longer I worked the options with no success, the more I hated whoever came up with the idea in the first place and whoever else thought it was good enough to slap on several model years' worth of what would have been decent bikes. The idiocy was industry-wide. Stupid, stupid, stupid idea. It cured the problem of cable chafe on the head tube at the cost of far greater functional problems with the shifting and steering systems.
The black bike defied my efforts to get a good picture of the setup in its mangled condition as I started the repair.
In this case, the problem is aggravated because the rider is a triathlete using aero bars with bar-end shifters. The pricey carbon aero extensions are drilled for internal cable routing. The stiff housing index shifting requires has to make two radical bends to get from the exit hole in the bar to the stop on the head tube.
The original housing, CD 4 mm, had broken through the alloy ferrule in the head tube stop. Incidentally, the ferrule was corroded into the cable stop because of the constant bath of salty sweat that poured onto it as the rider used an indoor trainer. The housing had twisted itself up into a strange curl under the wide wing section of the bar.
I had to drill the remains of the alloy 4mm ferrules out of the cable stops so I could install brass 5 mm. I still haven't solved the routing riddle. One option would be to remove the threaded stops and take the housing through the part welded to the frame, but that would look even more cluttered on the sleek road frame than the rat's nest of curled brake and shift housings at the head tube already does.
Trying to overcome gratuitously stupid design drives me INSANE. It's even worse when I'm trying to fit this repair in with a wad of other important stuff, for a rider who has trusted me numerous times with her race prep. So far, I've managed to come through every time. This is her last big race of the year, and it's in Arizona or something, so the stakes are high.
Like all tri bikes, it's crusted with sticky and salty deposits from the energy drink and perspiration that get poured over it day after day. The crust on the rear brake has actually hardened into rock candy. If she runs short of energy out in the desert, she can hop off and lick the brake for a while.
Speaking of sticky, this $5,000-plus marvel also had another of my nemeses, sticky-back cork bar wrap.
There is absolutely no reason to have aggressive adhesive on the back of your bar wrap. It just makes repositioning or reusing tape impossible and makes it more difficult to remove old tape to put on new. Unless you're some kind of twine-wrapping shellac-slapper, you WILL re-tape your bars. Just to change this rider's cable housing I will have to replace the little sections of cork wrap on the aero extensions because the sticky backing shredded what would have been reusable tape. I know this is just a nuisance, but it does add the cost and time of wrapping bars to a lot of repairs where it would not have been directly relevant.
Suppliers should say in the product description whether a model of wrap has adhesive backing.