I haven’t ridden a bicycle in 3 years, but when I did I had a small can of pepper spray for joggers on the handlebars. It had the little Velcro strapped holster that makes it easy to attach.
I also had my S&W 442 in a handlebar bag on occasion. That was almost a big mistake one day because I stepped away from my bike to buy a soda at a convenience store. When I came out of the store there was this guy wearing all the Lycra bicycling gear next to my bike getting ready to unzip my handlebar bag. Without boring you with the colorful conversation…His girlfriend had a flat. He needed a tire patch kit. He didn’t think I “would mind”.
Anyway, I bought an under seat mounted bag with quick detach straps for maintaining concealment when I had to leave my bike. The bag went with me.