I did it on a dare. A new service manager, I was probably feeling a little under-appreciated by my new boss, the shop owner. So one day one of the mechanics and I were talking and at some point I mentioned that it was possible to make a battery-powered Honda streetbike run without its battery, without adding any parts. Not many believed it. The boss overheard me and basically responded as if I was blowing smoke. Well, I couldn't let that go, pride you know. So I did it. I made it happen. I had never actually done it before, but being a mechanic who paid attention to things I worked on and one who thought a lot about things, I knew without a doubt it was possible. I just had never proved it before. Now it was time. Put up or shut up. Fortunately, it was a piece of cake. It was a Honda 125 single (CB125). Battery powered (Kettering) ignition, not a dirt bike, mind you. I simply removed the battery and wired the alternator into the ignition points, turning the alternator into essentially a magneto. The bike started and ran. And I was vindicated. Still got no respect from my boss however.....