I bought a bike that was already modified by the previous owner. One of the things he did was replace the rear turn signals with the bullet style ones and connect then to each side of the rear fender. The problem is that every time I ride, the rear turns signals don't stay put. I'll stop at a red light and look at them, and one will be pointing up and the other straight down. I asked somebody how to fix this and he gave me a pretty brief answer and didn't go into detail: something about putting a lock nut on or what have you. Anyway, can somebody give me a detailed explanation as to how I can fix this problem? I am not very handy with my hands. To get to the bolt that holds the turn signal, I have to get inside the rear fender.