The nationandrsquo;s first professional gravity mountain bike series, the USA Cycling Pro Gravity Tour will kick-off on May 3 with the Fluidride Cup in Port Angeles, Wash. Fluidride is the first of five events making up the 2009 Pro GRT. The top national-level gravity mountain biking calendar in the country, the Pro GRT is designed to offer a regular, competitive platform to recognize the best gravity athletes on U.S. soil.