I've built up a Domane SLR 7 and Service manual state says: "Make sure the plastic tails of the guide line up with the grooves of the frame"( page 15). Sure I did, but after a few rides my rear and front gears didn't work as smoothly as I expected. Examining the poor plastic and bare(!) wiring suggested by Trek it's obvious that it's a magnetic area for mud and dirt ( down under the bottom bracket shell). I'm looking for solutions better than Trek's Service Manual says. Someone got an idea?