2004 Yamaha YZ 85 Technical Analysis & Specification Breakdown
Positioned in Yamaha's cross - motocross motorcycle lineup, the 2004 Yamaha YZ 85 utilizes a 84.7 cc (5.2 cu in) liquid-cooled single cylinder, two-stroke layout. Internal engine geometry specifies a bore and stroke of 47.5 x 47.8 mm (1.9 x 1.9 inches) with a 8.2:1 compression ratio.
On the scales, the YZ 85 measures 66 kg (146 lbs) dry. Rider ergonomics and chassis geometry center around a 864 mm (34 in) seat height — reflecting a long-travel chassis stance that favors ground clearance and off-pavement control, combined with a 1,255 mm (49.4 in) wheelbase engineered for quick, flickable steering geometry.
Within MotoLibrary's Yamaha archive, this model family spans 5 indexed model years from 2002 to 2007, allowing buyers to track year-over-year changes in emissions tuning, weight and equipment.
Standover Height
864 mm (34 in)
Engine
Displacement84.7 ccm (5.17 cubic inches)
Engine TypeSingle cylinder, two-stroke
Engine DetailsSingle cylinder, two-stroke
Compression8.2:1
Bore x Stroke47.5 x 47.8 mm (1.9 x 1.9 inches)
Valves/Cylinder5
Fuel ControlDouble Overhead Cams/Twin Cam (DOHC)
CoolingLiquid
Chassis
Front SuspensionTelescopic fork
Front Travel275 mm (10.8 inches)
Rear SuspensionSwinging arm (monocross)
Rear Travel282 mm (11.1 inches)
Wheelbase1255 mm (49.4 inches)
Ground Clearance351 mm (13.8 inches)
Wheels & Brakes
Front Tyre70/100-17
Rear Tyre90/100-14
Front BrakesSingle disc
Front Brake Ø220 mm (8.7 inches)
Rear BrakesSingle disc
Rear Brake Ø146 mm (5.7 inches)
Dimensions & Weight
Dry Weight66.0 kg (145.5 pounds)
Seat Height864 mm (34.0 inches) If adjustable, lowest setting.
Use this page to compare this motorcycle by its real specifications, not only by model name. Focus on the details that affect fit, comfort, handling, range and ownership.
Seat Height
Check the seat height against your inseam and riding posture before choosing a motorcycle.
Weight
Compare weight carefully because it affects low-speed handling, parking and confidence.
Brakes
Brake setup is worth comparing if you ride in traffic, mountains or with a passenger.
Suspension
Suspension details can matter for comfort, road feel and long-distance riding.
