Mark,
When I transport my gun, its in a case, unloaded, on the seat next to me in my truck.
In addition, I transport my gun on my motorcycle. I ride a sportbike and the only place I feel comfortable transporting it where it won't fall off is in a magnetic tank-bag that sits on the tank of my motorcycle. Clearly within reach, and clearly concealed inside the zippered tank-bag.
If that isn't legal I will be EAGER to be the first test case.
I've discussed the issue with a knowledgeable attorney who is an expert in gun rights cases who shared with me that there has to be a practical manner to transport a firearm using the ordinary conveyances of the day (bicycle, motorcycle, scooter, walking, pickup etc)
If you are doing NOTHING else wrong, not engaged in ANY illegal activity, I don't think you'd have anything to worry about in the end. HAVING SAID THAT, it is clear for all of us here (the Brookfield incident being a perfect example) of the police behaving improperly. Illegal search, illegal seizure, illegal arrest.
MKEgal was, in the end, never charged, but that didn't mean it wasn't a huge hassle for her.
No one can promise you that you'll never have an unpleasant OC experience. We cannot be assured all police officers will follow the law and limits of their legal authority at all times.
Having said that, these examples if improper police treatment are definitely a rare exception. 1000's of people OC in Wisconsin every day and there are just a handful of incidents of improper/unpleasant police contact.
In the rare event there is improper police contact please let us at Wisconsin Carry know. Our mission is to protect and expand the human right you have to carry in the manner of your choosing. We've been able to obtain judgments on behalf of our members who's rights were violated. We continually review situations to determine if we have an opportunity to get involved legally to set precedents (practical and legal) that will deter other departments from infringing on the rights of law-abiding carriers.