Yamaha’s YZ250F now has more than a decade of being one of the prime racing motorcycles of the MX2/Lites division at the highest level. On its inception in 2001 it instantly established a new creed of motocrosser (the 250cc four-stroke) paving the way for the latest generation of MX2-GP classmachines. On the track the 2012 YZ250FM works prototype is again hoping to break barriers with a fully modified engine including modified fuel injection for a second season.

The YZ250F was an instant hit on its world championship introduction in 2003, dominating the second half of the 125 championship with Stefan Everts and claiming eight from nine races, scooping the manufacturer’s crown. In the first year of the MX2 category in 2004 the bike was again gracing the top step of the podium. The following campaign Italian Antonio Cairoli obtained a maiden title for the machine on an YZ250F prepared by famed tuner Claudio De Carli. He repeated his success in 2007 after finishing runner-up in ’06.

The YZ250F race-bike was updated for 2009 with a weight drop of 500g and a new lighter swingarm improving handling along with a redesigned rear hub. For 2010 the bike was again revised with a brand new engine, styling and centralisation of the chassis. For 2011 YRRD (Yamaha Rinaldi Research and Development) have embarked on an ambitious new prototype engine project including fuel injection.

The race-proven production YZ250F is an excellent base. In 2009 the motorcycle, in the hands of Christophe Charlier, won the extremelycompetitive MX2 European Championship; the Grand Prix feeder series and in 2010 Zach Osborne claimed the MX2 British Championship. In 2011 Gautier Paulin took the fuel-injected prototype to seven trophies while Osborne proved that there was life still yet in the carburettor and climbed the rostrum on two occasions. Team-mate Arnaud Tonus ensured the British Championship stayed in Yamaha hands as the duo dominated the eight round national series. Elsewhere Chiara Fontanesi finished a close second in the FIM Women’s Motocross World Championship.

The 2012 version of the YZ250F saw yet more refinements made to this capable motorcycle. A new bi-lateral beam frame with improved rigidity has seen enhancement in the already superb handling and a new lighter valve system and redesigned carburettor has added boost to the potential of the engine. The modifications are already proven with the bike carrying Osborne to his first career podiums (two from four appearances) in the AMA Supercross Lites series during January.

The 2012 YZ250FM factory bike, with a prototype fuel injection system and programmable GET ECU, will be steered by Christophe Charlier in yet another mark of development by the Rinaldi R&D division. The prototype engine will have a huge number of YRRD special Grand Prix parts such as cylinder head, cams, piston, crankshaft, conrod and is equipped with a hydraulic clutch.
Osborne and Tonus are fired up to fight for the 2012 MX2 world title using a Cosworth powered YZ250F engine entered by the Monster Energy Yamaha squad of Steve Dixon. Both teams will use Akrapovic exhaust systems in 2012 with the Rinaldi squad now also having made the move to the famous Slovenian manufacturer.

Teams and racers on circuits across the continent benefit from the acclaimed YRRD race kits with engine upgrades and components designed to allow the YZ250F to operate at the peak of its performance. For more details click here.