My bike fell last week and fortunately the only thing damaged was the rear turn signal which has always had a slight crack in it. This time it cracked all the way so that the tail light was angled down and a little to the rear. Although I have two good stems, I decided to attempt a repair since this seems to be a common problem. I thought about putting a splint on it but decided against that since I wanted the repair to not stand out like a sore thumb. The solution I finally settled on turned out to be very simple. I took one of the washers found in the female end of a water hose, cut through it so that I could get it around the stem and pressed it into the crack about 3/4 of the way around forcing the stem back into shape. I then split the remaining 1/4 of the washer and placed it in the remaining part of the crack. Since there were still some open spaces around the repair, I filled them with silicone. After the silicone cured, I tightly wrapped the stem with self amalgamating black tape. I don't know how long it will last, but it actually looks pretty good and from a distance it looks normal, notwithstanding the fact that the repaired stem is now about 1/8 inch longer.