I had an email from a reader about a month ago enquiring about an issue he had with his new Smart Lunar 35 lux light interfering with his wireless cycle computer, a Sigma 1009 STS. Unfortunately, it’s quite a common problem that LED bike lights and other electrical equipment such as electric bike motors can make wireless bike computers go haywire.
Various things can be tried to rectify the problem from moving the light or computer (or both). I’ve also seen it suggested that wrapping the light in aluminium foil or tape can help though I think it somewhat ruins the look. It may be that the lights made completely of metal are less prone to interfere.
Ultimately people who suffer from this problem usually end up switching to a wired computer which will always fix the issue. I like to use one with a temperature display which I find particularly handy as it gives me some idea of the likelihood of ice on those chilly mornings when I might have forgotten to check the weather forecast.
I think it would be useful to gather further data on compatibility between bike lights and wireless computers. I’d greatly appreciate it if you could post a comment below with make and model of your light and computer and whether or not you’ve experienced problems.