With a modern, sporting appearance, the XS 400 was produced by Yamaha from the mid-70s. The bike has a four-stroke, air-cooled, straight-twin engine and a six-speed transmission. The head has a single camshaft with 69 x 52 mm bore x stroke. In contrast to the other 400 models, the XS does not have counter balance shafts; this drastically reduces the level of vibrations produced. The XS 400 is a very lively, fast bike with high performance during pick-up. It can reach a top speed of 168 km/h in just 14 seconds.