If you are building a tricky Yamaha race engine then one of the most crucial parts needed it is the R&D cylinder block. Its unique port design, with the reworked angles and length provide outstanding horsepower increase through out the power band. These were the cylinders that developed with the scope to win with Nicloas Rius in 2000 at the World Finals. If you need a set of factory cylinders then call R&D. There are only a few left.
