Cable housings?

[DebW]

You're pretty much constrained by if/where the manufactured put cable stops on the frame. Since cables inside housing produce friction, running bare wires along the frame reduces friction, plus makes is easier to regrease the cables inside the housing periodically. Hydraulic disk brakes will always look like they have housing all the way, but that's a hydraulic line which must be continuous, not a wire in housing.

[pinkbikes]

Mine is like your Dh's. I have the front derailleur cable running naked and the rear derailleur cable running covered. In fact the rear derailleur cable runs covered all the way down to where it enters the rear derailleur.

My previous bike did not. I didn't really think about it from the aesthetic point of view of rubbing the paint, but rather the susceptibility of the bike to sucking nasty junk into the cable outers when riding in yucky conditions.

I had the misfortune to ride my old bike in a couple of races that were very wet and muddy. Lots of mud and grit got attached to the maked cables and when gears were shifted and the cables move longitudinally (so they go in and out of the outer housing) it sucked this muddy gritty muck into the outers. From then on it became a very unpredictable shifter until I had the outers removed and cleaned out.

My new bike has the advantage of being SRAM X-0 and also fully enlcosed and despite getting sucked into another two wet races it has been sensational - never missed a beat and cleans up perfectly. The front derailleur is not covered, but it runs in a spot less vulnerable to the mud, the front shifter doesn't require the same precision as the rear so is not so critical to keep squeaky clean.

My DH has just bought a cable set and changed his to fully covered as well. It was easy and inexpensive. But if you are not likely to ride in horrid conditions it may never be an real issue for you!