I ride a HD ElectraGlide. I don't have a radio and where it would be I have a zippered Cordura pouch that works perfectly to carry a small to midsized handgun. According to the police I have asked, the law here considers a MC the same as a car and you don't need a CHL to carry in this way.
I have traveled much of the country in this way and have found that it works for me. It's probably illegal in some states but that's not a problem unless, God forbid, I had to use it. In that case, as the saying goes, I'd rather be judged by 12 than carried by 6.
Or something like that.