Wireless sensor next to spokes? I don't get what you mean. Are you referring to the magnet attached to the spokes?

As far as problems with wireless... I have tried several different brands and models and had issues with all of them. I suspect that most folks have similar issues and just don't notice or are not bothered by them. The problems were never enough to make the device completely useless, but all that I tried were subject to errors the most common of which were that they logged some distance while parked in front of a store or diner close to a neon sign. It becomes especially noticeable when a group is riding together. We noticed on the TA that the three of us would be in sync before lunch and one who parked close to a neon sign had logged a couple miles while sitting still.

The errors were fairly small on the grand scale of a coast to coast trip, but big enough to be annoying when looking for something at a known distance into the day's ride.

Much less often I have seem sporadic errors like the times the computer read some impossibly fast speed. These were typically when near some kind of high voltage line like a power line or electric fence, but sometimes they occurred for no reason. These were rare enough that I would be willing to put up with them.