As you already guessed, this is special edition for YAMAHA Factory Supercross/Motocross Racing Team. The colour blue shows that it is in the same colour of the bike for the team.
MUDMAN is the series of the Casio G-Shock from the Master of G, which include the best of G-Shock wristwatches like FROGMAN, GAUSSMAN, RISEMAN and GULFMAN.
MUDMAN series features a watch that is made from thick rubber surrounding the dial and the button for mud-resistance ability.
G-Shock is also good for the motocross sport since it involves a lot of ‘shock’ from the bike to the biker. Maybe the bikers in motocross doesn’t wear the watch in competition, but it is useful for us, who doesn’t have the second man to keep our time. Dual Illuminator actually illumination that lit the digit and also the dial for complete info display at night.
Interested? Get more info here: http://www.casio-intl.com/wat/g_shock/
Want to buy it? Check it out here: http://www.lelong.com.my/Auc/List/2007-01DxSaleK621732_AUCTION_-CASIO-G-9000MX-2-G-SHOCK-MUDMAN-motocross-for-YAMAHA-resin-strap-blue.htm