"Harzer" is currently the world's largest functional motorcycle, and it's not powered by a standard engine, but rather one sourced from a T-34 Soviet tank. To be more specific, the T-34 was powered by a Model V-2-34 38.8 L V12 Diesel engine generating 500-horsepower, giving a top speed of 33mph. It used the coil-spring Christie suspension of the earlier BT-series tanks, using a "slack track" tread system with a rear-mounted drive sprocket and no system of return rollers for the upper run of track, but dispensed with the heavy and ineffective convertible drive. Click here to view the first image in this week's funny demotivational posters gallery. Continue reading for a viral video of a tactical team that has an unusual way of scaling walls (skip to 2:00).