KTM 65 SX
By TMX Archives on 2nd Jul 08
The most radical bike in the KTM range is not from the full-sized SX models, but the brand-new version of the all conquering 65 SX which was unveiled at the same launch and featuring a unique engine layout among off-road machines.
Already having virtually eliminated the venerable KX65 from the Junior ranks in recent years thanks to its superior motor and chassis package, the bike gets a total re-working with nothing left remaining from the old machine and a brand new motor featuring the gearbox mounted underneath the crank and a cylinder laid over at 45 degrees taking pride of place inside a brand-new frame.
In a design strikingly similar to the prototype four-stroke Husaberg motor developed by KTM - who own the name - this year, the 65 SX motor had been designed to seriously boost power output and centralise mass, and thus the crankshaft is hoisted upwards and angled forwards towards the centre of gravity, benefiting the handling and responsiveness of the bike, while the gearbox is moved directly underneath, allowing for a straighter angle for the intakes and reed block for improved performance.
A new powervalve has also been built into the motor to boost overall power and torque, and a new flat-slide 24mm Mikuni carb is also added along with the lastest generation V-Force reed block and new exhaust system to further aide throttle response and overall power.
The end result is a motor that produces significantly more power right the way through the rev-range and at the bottom and top-ends in particular.
To ensure the rider gets the best out of the new motor on the track a totally new chassis has been developed also with a brand new frame built using KTM's latest frame building technology, and new full-adjustable 35mm Marzocchi forks and revised WP shock fitted.
A new four-piston rear-brake is fitted to the new black wheels, while the newly designed bodywork mimics that of the full-size SX models and promotes much improved ergonomics and rider comfort. Pro Taper handlebars finish off the whole package which is sure to be at the top of every young racers wish list when it arrives on UK soil in the very near future.
Specification:
ENGINE
Type: Liquid-cooled single cylinder, 2-stroke
Displacement: 64.9cc
Bore x Stroke: 45/ 40.8mm
Carburettor: Mikuni VM 24-505
Starter: Kickstart
Gearbox: Six-speed
Clutch: Wet multi-disc clutch, hydraulically operated
Lubrication: Mixture lubrication 1:60
Primary Drive: 23:75
Final Drive: 14:50
Ignition: AET digital
CHASSIS
Frame: Double grinded central double-cradle-type frame
Subframe: Aluminium
Handlebar: Pro Taper, Aluminium 22mm
SUSPENSION
Front: Marzocchi-USD 35mm
Rear: WP mono-shock
Travel Front/ Rear: 220/ 270mm
BRAKES
Front: Disc brake, 198mm
Rear: Disc brake, 160mm
WHEELS
Front/ Rear: 1.60 x 14"/ 1.60 x 12"
DIMENSIONS
Steering Head Angle: 64.5°
Wheelbase: 1,137mm
Ground Clearance: 280mm
Seat Height: 750mm
Fuel Capacity: 3.5 litres
Weight (without fuel): 55.4kg
