I am doing my first build and my throotle and clutch cables are way to long. I know how to shorten them and i will wait until my build is finished before shortening them. I am going to have to solder the ends back on the cables. I have a spare brake cable from a bicycle to practice on. I am wondering if I can attach the ends back on the cables with rosin core 60/40 (60%tin/40%lead) solder and no flux paste. Can I use flux core solder instead of solder and flux paste? Thanks in advance for the help.