Velocity Top Velocity Stack Kit by Graves Motorsports®. Graves Motorsports Yamaha R1 Top Velocity Stacks 09-14Graves Motorsports Yamaha R1 Top Velocity Stacks for the 2009-2014 models. This “Upper” or “Top” velocity stack is sold seperately from the lower billet machined piece shown in picture ( Lower Part # ABY-09R1-REVB). The upper stacks must be used with a YEC ECU or Flash Tune and correct setting will be supplied to customer upon purchase.Developed by Graves for your Cross Plane Crank Yamaha R1. This stack kit improves power throughout the entire RPM range. The staggered tops allow the cylinders to share the available volume of air in the R1’s air-box evenly at low and mid range RPMs.The shorter than stock lower stacks feed the R1’s appetite for big air when the upper stacks raise improving top end power.These stacks were specifically developed on the Graves Yamaha Superbike give riders the drivability needed to win races.
Graves Motorsports® was born in 1990 out of the dreams, desire, and dedication. Both a manufacturer of performance accessories and a professional road racing team, Graves Motorsports provides privateer racers with factory-quality, race-proven performance parts. Dedicated to total customer satisfaction, the company has a growing list of trick performance items available for the Yamaha, Suzuki as well as other brands. Graves Motorsports makes rear sets, bars, exhaust systems, velocity stacks, suspension components, marker lights, fender eliminator kits, and on and on. At Graves Motorsports, they believe that craftsmanship leads to championships! All Graves Motorsports parts are designed with the utmost attention to detail using the latest equipment to ensure winning performance and unbeatable longevity.