A few years ago we babysat my grandsons dog during the day and I was busy working on motorbikes, mostly single cylinder. Cocker Spaniels are not the brightest and every time I started one up the dog would wrap his mouth over the exhaust pipe, chase him away and he would be straight back. One day after just restoring an early 40's Enfield for a mate, I hadn't fitted the exhaust, I started it up and because there was no exhaust the dog raced to the back of the bike, no muffler to grab on, he took a bite on the freshly painted tool box and put teeth marks in it. I was not a happy camper.