NEW FEATURES ON KTM FULL SIZE 2-STROKE MODELS

The main focus of the 2000 KTM 2-stroke line is to draw, for the first time, a clear distinction between SX and E/XC models, thus signaling independent Motocross and Enduro product line development in the future.

The complete 2000 2-Stroke model range is equipped with the new WP USD(Up Side Down) 43 mm front fork. The WP USD 43 is a . Multi-Adjuster" . fork, which means the rebound- AND compression settings can both be adjusted on each fork, which means a very large regulation range. In contrast to the WP Extreme fork, the USD 43mm fork weighs considerably less, offers extremely improved response, provides increased rigidity and comes in 3 different basic settings. On each fork the rider can choose his/her personal setting from 2 X 26 adjustment variations.

A new lower fork axle clamp: lightweight, compactly formed and high quality forged component..

Newly designed, silver colored 180° fork protector, delivers maximum protection for the USD sliding tubes.

The 2000 WP PDS shock absorber has a new setting.

The upper triple clamp is new. It. s forged with an undamped, variable handle bar position attachment. Not only can the handle bar be mounted on the triple clamp in two different positions (further to the front, or further to the back), the 22mm-diameter handle bar attachment also has eccentrical holes that offers further variation possibilities for the handlebar mounting position.

FOOT PEGS

The SX-models have 10 mm longer foot-pegs that offer greater arch support and distribute impact over a wider area. A real benefit on harsh landings from long jumps.

The complete 2-stroke range has a new rounded profile swingarm with extended 32mm long axle slots. A newly designed chain tension unit offers quicker and more exact adjustment when changing gearing. Precision milled adjustment marks allow optimum chain tension and proper rear wheel alignment. The chain adjusting bolts are reinforced. The swing arm pivot bolt is also new.

2000 models receive numerous brake system improvements:

The rear brake master cylinder has a smaller piston (12 mm instead of 13 mm), resulting in considerably improved modulation.

The front brake master cylinder is smaller, lighter and true . racing style". The front brake lever on all SX models (and EXC/MXC USA models) has a spring pre-setting, which not only makes the lever position infinitely adjustable but also keeps the lever exactly in the adjusted position (no freeplay any more).

The front brake caliper has a new mounting bracket which is completely torsion-resistant and together with the new Toshiba TT270 brake pads, increase braking power by 10%. They are most improved in full traction conditions. The result: dramatically improved braking performance.

The new designed brake disks are designed for maximum dirt repelling ability. The curvatures on the outer radius transport dirt from areas like the slots where debris is prone to collect. Wedge-shaped holes, reach past the brake pads, forcing dirt out towards the inner side. The brake disks are mounted directly on the hubs, and (on the EXCs) have a magnet sensor for electronic odometer already integrated.

The complete 2-stroke range has new, lightweight and nickel-plated front and rear hubs. The front hub is equppied for the larger 20 mm front axle (previously it was 17 mm) that is required by the 43mm WP fork. The new axle increases frontal rigidity and adds stability allowing the front fork to work at its optimum.

& New, lightweight 4.5mm double-tapered spokes in the front wheel, and extra strong 5mm spokes in the rear. Both spokes are chrome-plated for corrosion resistance, and continue the reputation of strength and durability KTM wheels are famous for.

New FIM-silencer on all SX models.

The new silencer is round with a smaller diameter of 69 mm. It provides a decisively higher power output with an equally impressive . sound".

The new final db rating corresponds to the latest FIM regulations.

(USA: Odometer unchanged, Australia: Facomsa speedometer)

The homologated EXC bikes in Europe are generally equiped with the electronic speedometer, having 5 different functions, but no ignition lock. The simpler cable harness saves weight.

Orange is the color of the KTM sport presence. The sport oriented 2-strokes therefore keep their orange-silver basic colours. The graphic design is an updated retro design in silver-black.

All EXC models come equipped with a side-stand.

All 2000 2-stroke models come equipped with Bridgestone tires as OEM.

The 250 engine has a new bore/stroke relation, resulting in vastly improved throttle response and increased power output(especially in the mid and upper rpm range): 72 x 66.4 mm (before 67.5 x 69.5 mm).

The engine cases have been modified resulting in a significant increase in power output, through a flow-optimized reed intake channel. New designed ignition cover.

The 250cc cylinder has a new exterior design: with a larger water housing for optimum operating temperature and more safety against overheating. It also provides increased water volume in the cylinder head.

The crankshaft is modified to compliment the new bore/stroke relation. Additionally the con rod is shorter (129mm instead of 132mm), and the compression height of the 250cc piston is raised by 11 mm.

The new 250 SX engine has an absolutely (to the max) weight reduced crankshaft with two wolfram/tungsten inserts. With it?s greatly reduced overall weight the crankshaft the engines revs more quickly and accelerates faster.

The exhaust pipes of all 200/250/300 models have been redesigned to work in conjunction with the corresponding engine modifications.

The exhaust pipes of the EXC models are double-skin in the front lower part, similar to what KTM has used for years at the ISDE events. Being double-skin in this area alone has the advantage of having an exhaust pipe that is less susceptible to damage but has a maximum of power-output and the lowest possible weight at the same time. The pipe mounting of all 125/200 models have a new cylinder-shaped flange with two O-rings, guaranteeing an extra-tight fit and perfect sealing at the cylinder/exhaust passage.

The new 250 SX comes with a Keihin PWK 38 PJ AG (PJ = Power Jet).

It functions in combination with the new Kokusan 2K4 ignition, which regulates the Power Jet Control.

The 2K4 ignition directs a magnetic valve on the carburetor, that opens and closes the injection jet (. Power Jet"). This . Power Jet" provides additional fuel supply at the highest torque, which results in an improved torque . curve.

All KTM 2-stroke models (exception 125 SX) have a Keihin Carburetor AG (=Air Guide). These integrated air guides direct the air flow in the most efficient manner, which results in an increased power output.

The 125cc KTM piston is constructed from a new, extremely wear-resistant alloy, and . depending on the model; one piston ring(SX models), or two piston rings(EXC models).

New Kokusan ignition 2K2 (before 2K3). The 2K2 has a smaller flywheel (diameter 77 mm, earlier 106 mm), and due to it?s compactness results in better engine response.

As far as its basic structure is concerned, the main frame of the SX and EXC Racing models precisely corresponds to the frame geometry of the KTM 2-stroke models. Only the split cradle down tube sections, which were adapted to the 4-stroke engine, and a few retaining brackets were slightly modified. The sub-frame is made of aluminum and fixed to the main frame by means of a screw connection.

The 2000 Racing models are equipped with the new 43 mm WP USD (Up Side Down) fork. The WP USD 43 is a . multi-adjuster" fork, which means that both the compression damping and the rebound damping can each be separately adjusted on either fork tube, thus offering an enormously large regulating range. The WP USD 43 fork is very light and has different internal settings for the SX and the EXC models, respectively.

2 x 26 adjusting positions on each individual fork tube allow precise adaptation to individual needs. The forged fork leg axle clamp is light weight and offers maximum ground clearance.

A newly designed silver-colored 180° fork protector ensures maximum protection of the USD immersion tubes.

The WP PDS Shock Absorber 2000 is specifically . racing-adjusted" for both the SX and the EXC design.

TRIPLE CLAMP / HANDLEBAR MOUNTING SYSTEM

The top triple clamp is forged with an undamped, variable position, handlebar clamp system. The handlebar clamps can be attached in two optional positions to the triple clamp (i.e. front and back position). Additionally, the handlebar clamp itself, with a diameter of 28 mm, has an eccentric bore, thus offering additional opportunity for variation of the handlebar position.

Result: the widest range of individual handlebar adjustment ever offered by KTM

The tapered handlebar is a new Magura Aluminium handlebar, a sport handlebar directly from the racetrack:

The footrests of the SX models are 10 mm longer to reduce the danger of slipping and ensure that the rider is supported squarely, especially on landings from high and long jumps.

The Racing models have a high-quality swing-arm with a rounded profile and new axle passage. The chain adjusting mechanism can be rotated 180 degrees to allow rapid changing of final drive sprockets. Exactly milled marks allow precise chain adjustment and exact rear wheel alignment. Strong tensioning screws, new swing-arm pivot.

The foot brake cylinder of the Racing models has a smaller piston diameter (12 mm), which gives the rider a significantly better opportunity to apply the precise amount of brake pressure required.

The front brake also allows better modulation of brake pressure: the front brake cylinder is small, weight-optimized and a real . racing feature".

The front brake lever of the SX models is provided with a spring preload feature which not only allows exact adjustment of the lever position but also keeps the lever precisely in the selected position.

The front wheel brake caliper has a newly designed brake caliper support. The new design will not flex and ensures, in combination with the new Toshiba 1 12701 brake linings(which have 10 % more braking power and work best on surfaces with good friction characteristics), the best possible brake performance.

The special-shaped brake disks include features that limit the accumulation of dirt to a minimum. A cambered outer radius ensures that dirt particles, which tend to accumulate above the slots, are removed. The wedge-shaped slots, which protrude beyond the path of the linings, cause the dirt particles to drift off toward the inside. The brake discs are mounted directly at the hubs. Those of the EXC models have the magnet directly integrated.

The complete 4-stroke Racing range has new, lightweight and nickel-plated front and rear hubs. The front hub is equipped with a larger 20 mm front axle (previously it was 17 mm) that is required by the 43mm WP fork. The new axle increases frontal rigidity and adds stability allowing the front fork to work at its optimum.

New, lightweight 4.5mm double-tapered spokes in the front wheel, and extra strong 5mm spokes in the rear. Both spokes are chrome-plated for corrosion resistance, and continue the reputation of strength and durability KTM wheels are famous for.

KTM's own high-capacity silencer combines sleek racing design with heart-pounding four stroke acoustic properties. SX and EXC silencers are the same as far as diameter and length are concerned. However, their interior components are different and adapted to the respective requirements.

(USA: odometer; Australia: analogous speedometer)

EXC Racing bikes in Europe are equipped with an electronic speedometer and have no ignition lock. The overall weight is reduced due to the simplified wiring harness.

The color of the KTM sport performance is orange. KTM Racing models SX and EXC are designed to match the look of the 2-stroke sport models. The basic color combination is orange / silver. The decoration of the 2000 models is familiar from the Motocross World Championships: highly fashionable retro design in silver / black. A matching non-skid seat cover is available.

SX models are additionally provided with white number plate backgrounds.

EXC Racing models are equipped with aluminum side stands.

EXC bikes are equipped with the latest model of KTM flashers: small and sportive, oval.

SX and EXC Racing models all come with Metzeler tires.

SX: front wheel/ Metzeler MCE 2, rear wheel/Metzeler MCE 4.5 or 8 Motocross (?)

EXC: front wheel / Metzeler MCE 2, rear wheel / Metzeler MCE Six Days 2 (?)

SX Racing with Excel(19" Rear), EXC Racing with D.I.D(18" rear).

KTM Racing models are equipped with a totally new engine developed by KTM: new centercases, new transmission, new head new cylinder, new covers. Everything is new.

Important feature: The kickstarter is located on the right side of the engine. The original starting point of development, the Husaberg engine, has virtually disappeared. The clutch is the only component that has not been changed. All other components were developed by KTM and are totally innovative:

The weight difference between the SX and the EXC model is approximately 8 kg. The total weight of the 520 EXC (ready for operation but without gasoline) is approximately 115 kg (dry weight approx. 112 kg), the total weight of the 520 SX (ready for operation) approximately 107 kg.

The sand-cast aluminum centercases are considerably stronger (up to 20 %) than die-cast centercases. The surface of the bottom is flat (like a skidplate) thus largely preventing the motorcycle from catching on uneven terrain. For optimal heat dissipation and a high-class sportive appearance, the centercases have no surface coating.

The new 4-stroke Racing engine is narrower than the current KTM 2-stroke engines.

Sprocket alignment is the same as in KTM 250cc 2-stroke models, but the transmission cases are 12 mm narrower on the right side (clutch side). The ignition cover and the clutch cover are made of lightweight magnesium (powder-coated or nickel-plated?<)

The transmission components are not mass-produced but cold-sunk, which is an extremely accurate forging technique that ensures top quality and durability with minimal machining. The SX version has 4 gears, the EXC version 6 gears. Conversion is relatively easy and requires only 2 gear wheels.

The SX version is equipped with a kickstarter, the EXC version with an additional electric starter which can, at least theoretically, be subsequently installed in SX models as well. The electric starter is located directly behind the cylinder and engages on the primary gear side.

The entire electric starter unit stands out for its remarkably low weight: the starter engine weighs only 0.88 kg (!). By comparison, the small electric starter of the LC4 weighs 1.2 kg, and the Husaberg starter an even 2 kg. Therefore, an extremely light 4 Ah battery can be used. This battery is mounted in the air filter box.

The kickstarter is constructed of aluminum. The kickstarter shaft, the starter and the ratchet gear are top-quality, high-strength cold-sunk components.

In addition to the automatic decompression (all models), the bikes also feature a hand decompression lever which is particularly appreciated for starting requirements under all conditions.

KTM Racing models are equipped with 2 oil pumps. The first oil pump draws oil from the gearbox and is filtered via two filters (1 paper filter, 1 microfilter). The oil is then pumped simultaneously to the camshaft(also lubricating the top end) and to the crankshaft. The second oil pump returns oil from the crankcase to the transmission system.

All oil lines but one are integrated into the centercase. There is a total of 7 integrated lines. Integrated oil lines are less likely to be damaged and significantly reduce the overall weight.

An oil level viewer replaces the oil dipstick. The microfilter is integrated into the centercases, unlike the LC4 which has a separate housing and external oil lines.

The new racing engine is unique in its central, low-weight ventilation system which works via the balancer shaft. A centrifugal oil interceptor prevents oil from leaking out of the engine through the ventilation openings.

The 520 engine is equipped with a forged piston. All components are top quality: precision-forged rocker arms, nitration-hardened valves, progressively wound valve springs on a two-spring system basis, aluminum spring retainers with very special valve guide seals as well as case-hardened adjusting screws. The timing chain is narrow, divided and riveted.

The cylinder, in contrast to the LC4, mounts in unison with the cylinder head to the centercases which means a weight reduction of more than 1 kg for the cylinder alone.

The crankshaft is designed as an absolute light-weight without any reduction in flywheel effect (0.65 kg lighter than the crankshaft of the 540 SXC).

A needle bearing for the conrod and a silver-plated cage as well as roller bearings for the crankshaft are standard features of KTM sport engines. Racing engines are equipped with a balancer shaft.

Racing models are equipped with a digital Kokusan ignition system. The SX version weighs 0.4 kg less than the EXC version where the lighting capacity must meet the applicable homologation requirements. The rotor diameter is 80 mm in SX models and 106 mm in EXC models.

The Racing carburetor is a Keihin with a throttle position sensor. In combination with the digital ignition system, information on both the current r.p.m. and throttle position is transmitted to the ignition box. The ignition curve is optimized for every load condition which improves engine response and reliability.

New: direct connection between carburetor and cylinder head. A rubber boot instead of an intake flange means better, performance-optimized inflow.

Racing models have a high capacity water pump integrated into the cylinder head.

The cylinder head is characterized by a new flow pattern. The flow is guided around both the intake and the exhaust port channels.

Racing models have no separate outer clutch hub. The function of the outer clutch hub is performed by the clutch gear. Therefore, the clutch can be designed extremely narrow, using extremely thin clutch discs.

Each of the two oil pumps is additionally protected by an oil screen of its own. These screens can be removed from outside and easily cleaned. They are sealed with reusable O-rings.

The two oil filters are easily accessible from outside as well and provided with

one single cover. The paper filter is shorter than the microfilter to prevent incorrect

installation of the filters. The oil pressure relief valve is integrated and accessible

from outside. The cylinder head is provided with the largest possible valve covers

to facilitate access. Dirt-repelling and torque-resistant hexagon screws are used as a rule.

The KTM Racing models 400 and 520 are true racing motorcycles with uncompromising racing engines specially developed for off-road riding. The EXC models are homologated but cannot unconditionally be recommended for road use for several very important technical reasons:

The new 4 Stroke racing engines have no mechanical ventilation (very important in stop & go traffic), no dampened clutch due to the narrow and lightweight design (therefore faster clutch wear), a narrow 5^th and 6^th gear (not designed for permanent stress), and only the absolutely minimum required quantity of oil. They also do not feature an oil cooler or frame oil reservoir.