The success of the new wave of four-stroke motocross bikes has led some manufacturers to give up developing two-strokes. But not Yamaha. Every year our engineers seek to refine and further develop the blend of light weight, hard hitting power and easy maintenance that characterises our two-stroke MX range.

Some have tried to imitate the magic inside the YZ250's compact liquid-cooled cylinder, but there's never been a match for that seamless surge of roll-on power all the way through the rev range. Meanwhile, the lean and scalpel sharp YZ125's flexible power delivery means it is still among the smartest launching platforms from which a young junior motocross rider can learn the tricks of the sport.

And Yamaha continues to offer two versions of the YZ85 - junior's very own factory motocross bike. That's 85cc of lightweight, liquid-cooled, crankcase reed-inducted thrust slotted under a flat, roomy cockpit designed for perfect pilot movement. Particularly when it comes with potent mid and top-end punch, a slick six-speed gearbox and the handling and braking to convert brute thrust into wicked lap times.

The 250 and 125 have many refinements for 2008 to make them sharper and lighter than ever. New front ends benefit from a range of lightweight components, including new fork outer tubes, fork protectors and a redesigned axle which deliver even lighter steering. The new ultra-compact YZ250F-type front caliper and master cylinder shed even more grams and ensure outstanding braking - and new wave-type discs at the front and rear look great and cut unsprung weight.

In addition, the YZ125 sports a redesigned reed valve spacer that optimises flow volume and flow speed across the full rpm range from low to high rpm to improve acceleration. Meanwhile, it's a case of don't change when you're winning for the YZ85s which simply receive trick black paint for their high tensile steel frames.

This quest for perfection has meant that the YZs have been the winningest two-strokes in the business for years. The amazing versatility of these models has led to some fantastic race results in 2007... and not just on the motocross track.

For example, Ballards enduro ace Jarrod Bewley has been at the pointy end of the Yamaha National Off Road Series (YZ250), Kirk Hutton finished an amazing sixth outright in the gruelling A4DE on his YZ125 and Showtime FMX rider Steve Mini has been thrilling crowds nationwide on the Crusty Tour (YZ250). New Zealand has a world motocross champion in YZ250 rider Tony Cooksley who easily won the Veteran's World Cup in Europe while Darryll King is the current NZ 250cc 2-stroke champion.

Plus the 85cc riders have been kicking goals with Joel Milesevic winning a 2007 Victorian State MX title, Keiran Leigh an 85cc NZ title and Luke Temple a 125cc NZ title. And Aussie teenage freestyle sensation Tyrone Gilks is planning an 85cc world long distance jump on his YZ later this year.

So whether it's MX, SX, freestyle or enduro... or distance jumping, the YZ two-stroke range looks set to remain in the limelight for 2008 and beyond.