Some bike computers are more heavily influenced than others. I mount my batteries on the stem RIGHT NEXT to the computer. One is a Sigma Rox9.0, the other isa Specialized (whatever they're selling right now wireless). I've only experienced interference once out of the Specialized. NEVER from the Rox. Of course, I'm using a TridenX, not the magicshine. Their may be some design there that minimizes wireless interference that the Magicshine does not possess.