2009 Husqvarna WR300 is not only a transformation kit which bigger than the predecessor WR 250 but also a perfect replica of the winning machine raced by Seb Guillaume in Class 3 of the Enduro World Championship series. New components and change features for engine include changes to the cylinder head and exhaust pipe in comparison with the 250 version, engine now features a V Force reed valve system, new bigger 38 mm TMX Mikuni carburettor, and a completely new exhaust valve.
Source about Husqvarna WR 300 via motorcyclespecs
