Some years ago I bought a Yamaha XS650 and spent a year rebuilding it. It's a 650cc vertical twin, with the pistons working up and down in unison, but on opposite strokes. As a consequence, she vibrated quite a bit, and on the centrestand would march around the shed. I actually thought I needed glasses, but my blurred vision was only at 100km/h. Well, I went touring on this bike with a bunch of friends, and at one stage one of my companions needed a new tyre for his BMW R100. We were all parked up out the back of the bike shop, milling around and chatting over a coffee when the young motorcycle mechanic wandered out and was looking at the bikes. "Who's riding the Black Dildo?" he said, indicating my beautiful XS...... My mates fell on the ground laughing, and forever after, my Yamaha was the "Black Dildo".
