You see, I didn't lock it up and so I shrugged my shoulders and walked home. With my mind on the missing bike I hadn't realised I'd walked the first five minutes with the helmet still on my head.
The bike was second-hand, cheaply made and struggled to change gears. I treated it with disdain, often leaving it out in the rain.
This, I decided, was a great opportunity to convince my wife I needed a new bike.
It was time to really get into cycling and that meant caring for my next bike.
I was ashamed of the disrespect I showed my bike, using and abusing it to get me to and from work. It was pure laziness. And now here I was trudging home with just a helmet in my hands.
The bike was my companion and did the very important job of getting me to and from work. I had nonchalantly left it outside in the wind and rain and, crucially, unlocked.
I bought a second-hand road bike from a friend. It had solid components, despite being a little small for me. You can go and get a new road bike but that is going to cost thousands of dollars.
This bike was half the weight of my last one and changed gears with ease.
I was cycling much faster and with a lot less effort than the tense work of my old bike. This is what cycling should be. Legs churning and the bike moving with ease.
It made beautiful tick-tick-tick noises as the chain ran through the various components and the pedals went around the bottom bracket - all without a hitch.
A bike needs more than just to be ridden and locked up carefully. It needs to be cleaned and lubricated regularly and I'm determined to keep this thing running smoothly.
There are countless resources about looking after your bike, but, and I'm sorry to sound like an old school teacher, the most important resource is your own interest and effort to keep on top of it.
And so I have entered a healthier relationship with my bike instead of one of neglect. That has meant getting a solid lock, and where possible keeping the bike stored inside.
I have been invited to join a cycling meet-up that goes out for coffee on the weekend. The cycling clothing is my next purchase.
I guess a thank you is in order to the man who stole my bike for inadvertently setting me on this cycling journey.
I can only hope he treats that bike better than I did.