In Illinois no open carry allowed as far as I know. I usually carry when riding a bike for reasons that I haven't seen mentioned, dogs. They love to chase people on bikes, I haven't been bit yet but I have been worried more than once. For someone that wants to carry on a bike, there are lots of options. You can't wear tight biker pants or shorts but something like a Ruger LCP can fit into a pair of shorts pretty easy. Island Tractor, kids grabbing your guns? Really? Of all the things I worry about when riding my bike it isn't some kid grabbing my gun. One of the most quoted stats by anti gun people is that a gun will more likely harm a family member than protect them. ITS NOT TRUE!
Dodgeman, I have to disagree with some of what you say. First, I have no problem with you carrying ( as long as you are a permit holder and qualified). But to justify that because of dogs? I'm a longtime cyclist. I've been chased by more dogs than I care to remember. Big ones, small ones, even almost got wiped out by a chicken. But never, absolutely never would I think unholstering a handgun while being chased by dog would be wise. I cannot imagine anything more dangerous than riding a bike with one hand on the bars and another on the trigger. If I were riding with you, I would never do it again. To fire a shot in a panic situation, while going fast, is crazy. First, your chance of crashing is very great. Second your chance of injuring a bystander or fellow cyclist is also great. The chance of angering the dog owner is great. Then you're at his mercy. If he retaliates and runs you over with his truck, you lose.
When a dog chases a bike, it's by instinct. They like to chase. They also are protective of their turf (the road in front of their house). The common scenario is this. Riders go by, dog chases. Rider panics. Either you can ride faster and try to outrun ( sometimes works) but often doesn't. Then you're faced with what to do. Pulling out a weapon, in my opinion, would almost never be wise. You may say that you will stop and dismount, then pull you weapon? Probably a better choice but unnecessary. When you stop, the dog loses that instinct to chase. You now become the aggressor. Put your bike between you and the dog and yell with your meanest voice. Stand your ground. Almost all dogs will back down. Then as you move away out of his territory, he loses interest. Or do what I do if I'm sure I can't outrun him. Slow down, let him come up beside you then blast him directly in his face with a stream of water from your bottle while screaming at him to go away. It works almost every time. I can think of only one time I had to dismount.
Dogs are very dangerous to cyclists! But almost never is the injury a bite. It's usually a crash caused either by the rider panicking and doing something stupid that either crashes him or perhaps a riding companion beside him. Or by the dog chasing one rider and then being hit by the following rider the dog doesn't see. Or the dog cutting in front of you and clipping your front wheel, causing you to crash.But regardless, I would rather have a nip on my calf than crash at 30 mph. Crashes will break collarbones, fracture skulls, and generally mess you up.
I just don't see how having a weapon changes this dynamic. Oh, pepper spray is ok, but I've found I get more on me than the dog. And the range is still only a few feet, so you've got to let the dog get in close. A water bottle blast and a loud yell works just as good for me.
So not trying to argue, but I think carrying a weapon to deal with dogs is not wise. Carrying one for protection against two legged threats is another matter, and is your choice to make. Lastly, shoot someone's beloved pet, even in the road in front of his house, is a situation destined to escalate. Either the owner is going to prosecute you, or chase you in a vehicle to confront you. You lose either way.
Be safe on that bike!