While modern Shimano 105, Ultegra and DuraAce shifters route the shift cables under the handlebar tape, some other Shimano shifters route the cables perpendicular to the lever. This cable routing can be problematic if you want to mount a large handlebar bag to a bike with Shimano Sora or similar shifters. A customer had this problem today, but I knew about the trick of using a V-brake noodle to put the right bend in the right place to make things work. The Crazy Randonneur had a great post on this subject just about a month ago and you can read that at:
Below are a couple of pictures of the bike I worked on today. A couple of V-Brake noodles and a bit of cable trimming and the shifters are now peacefully coexisting with the big handlebar bag.
Keep 'em rolling,
Kent "Mountain Turtle" Peterson
Issaquah WA USA