I've been studying EFI and digital controls and microprocessors on vehicles like my race car. I'm learning anything with a collapsing magnetic field or electric motor can make a voltage spike that travels back through the electrical system causing electronics to have problems. The best solution is to run the power feeds and grounds of sensitive items as directly to the battery as possible. The battery will somewhat absorb the spikes.
We don't have many spike inducing items on our relatively simple bikes but may be able to avoid problems as we get more sophisticated.
