Fuel injection (F.I.) is a feature that aims to improve the basic running performance while also improving environmental performance at the same time. Yamaha began research in turbo charging and F.I. Back in the 1970s for the “Toyota 7” racing car. That led to the first mounting of an F.I. system on a Yamaha motorcycle with the XJ750D in 1982. Then on the 1992 model GTS1000, Yamaha used a combination of F.I. and a 3-way catalytic converter to achieve heightened running performance and environmental performance at the same time. Since then Yamaha has continued to perfect its F.I. Systems from both the running performance and environmental aspects. The space and layout limitation of motorcycles in the 50～250cc range formerly made use of F.I. difficult, but measures to simplify the sensing and injection systems made it possible to successfully mount its Majesty125FI model with F.I. In 2002. Today many Yamaha motorcycles from 50cc to the large displacement models are mounted with F.I. Systems.