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The standard for modern sport ATVs was set by the Suzuki LTZ 400. It debuted on the market after Suzuki's sport quad stability of ten years, making its introduction much anticipated. There was no better time to achieve this than the early 2000s when 400cc racing motorcycles were at their most popular.

Between 2003 and 2018, the entire ATV industry was dominated by the Suzuki LTZ 400, also known as the Quadsport Z400, a powerful quad. This vehicle, regarded as one of the best sport ATVs ever made, has a rugged 398-cc engine, long-travel suspension, and aggressive bodywork.

In addition to having superb aerodynamics and construction, the LTZ 400 was renowned as the first ATV to defeat two-strokes in MX events and racing circuits. This is just one of the many excellent qualities of the ATV.

suzuki yellow four wheel

How To Adjust Valves On Suzuki LTZ 400

Regular maintenance is necessary to keep your ATV running efficiently, including adjusting your valves. Valve maintenance is often only required every few months for several machines, but for high-performance ATVs, you must inspect them after three to four routine maintenance.

Cylinder head cover removal When removing the engine cover, it might be required to remove the distributor to empty the vacuum advance. Next, loosen the ignition glass cover from the gear cylinder of the gearbox while positioned in the driver's position and inspecting the intersection of the engine and the transmission.

That tiny, filthy rubber plug is the issue; when looking at the crankshaft from the side of the truck, turn it forward. Next, align the gearbox case's notches with the "T" on the crankshaft. Finally, after removing the distributor cap, ensure that the blade is in the indicated position.

If the blade is out of position, turn the flywheel 360 degrees forward. It is heading to the first plug wire. When the engine is in this alignment, the valves at positions 1, 2, 5, and 7 should be checked and adjusted. Next, inspect the valves at 3, 4, 6, and 8 by rotating the crankshaft one round.

As the valves are modified, you should label them with a small amount of oil. The rocker's arm rides on the "Heel," or low portion of the cam. The locknut on the first intake valve should be loosened using a flat-bladed screwdriver and a 12 mm wrench.

A 14mm width gauge should be placed between the adjustment screw and valve. The adjustment screw should then be gradually tightened until it reaches the valve. Secure the locknut while holding the adjustment screw in place so it cannot turn. Place the 14mm and 16mm gauges after removing the 14mm gauge.

The 16mm should not go, and the 14mm should. Use the 15mm that we chose as our ideal measurement at this stage, and check how it fits or "Feels" as you move it back and forth between the rocker arm regulating screw and the valve.

Apply a small grease to the valve to indicate it is finished, then turn to the other valves. Complete this process for each valve. Next, complete the other valves by turning the crank as directed above.

2004 Suzuki LTZ 400

2004 Suzuki LTZ 400 was the second model of the Suzuki LTZ 400; it includes many similar features to the first model. The addition of a reverse gear among its 5-speed transmission, which contributes to its exceptional handling on forest roads or dirt tracks, set the LTZ 400 apart from its rivals.

Additionally, it adopted the same valvetrain architecture as its parent DRZ400S and featured a push-rod clutch arrangement similar to the Raptor. The LTZ400's engine control system was further enhanced by allowing the tires to connect for increased traction when it detected wheel slippage.

This improvement reduced the quad's launch time and improved the machine's overall stability and predictability. In addition, the brakes on the front are two hydraulic disc brakes, while the brakes on the back are one hydraulic disc.

2003 Suzuki LTZ 400

The multinational Japanese company Suzuki Motor Corporation created the 2003 Suzuki LTZ-400 ATV. The 2003 Suzuki LTZ-400 received a positive review from ATV Connection magazine, which praised its control and aesthetics as superior to those of other ATVs in a similar price range.

The 2003 Suzuki LTZ 400 has a length of 72 inches, a width of 45.9 inches, and a height of45.7 inches. It has a 10.4 inches ground clearance and a seat height of 31.9 inches; the wheelbase measures 49 inches, and the vehicle's total weight is 372 pounds. This ATV uses a 4-stroke, liquid-cooled, 398cc engine with a 4-valve cylinder.

Suzuki removed the DR-Z400S dual-purpose vehicle's highly regarded power plant for its modern sports quad. Instead, the vehicle's engine characteristics were slightly altered to provide more horsepower in the low-to-mid range while maintaining great top-end power.

This engine has a cylinder made of aluminum alloy with SCEM plating. With greater heat transmission and piston-to-cylinder spacing, this cylinder is more lightweight than traditional designs. Additionally, this cylinder incorporates internal oil passages that eliminate the need for external hoses, reducing weight.

The Quadsport Z400 has a 5-speed manual transmission with reverse gear. The clutch is a lightweight drive mechanism with an aluminum push rod and has a lovely, lightweight feel. The reverse knob resembles the Raptor much in appearance and placement.

Select first gear while keeping the clutch in to enter reverse. The shift lever should be moved from first to reverse after turning the reverse knob. The spacing and operation of the gears appeared to be excellent.

Suzuki developed the chassis to have just the appropriate balance of flex for maneuverability while still being sufficiently rigid to withstand the Z400's power. High tensile steel makes up the chassis, which has a detachable rear sub-frame.

men drive yellow atv

LTZ 400

The Suzuki LTZ400 dominated the sport class before Suzuki's Quadracer 450R, and the Yamaha YFZ450 entered the market. The QuadSport Z400, as this 44 was sometimes called, had a max speed of 70 mph. It included a 5-speed manual transmission, adjustable shocks, and a tubular frame with a racing aesthetic.

The LTZ 400 also had a powerplant from the DRZ400, bright yellow bodywork, and increased fenders, giving it the appearance of the ideal play vehicle. The four-wheeler was among the first vehicles to revive the 4×4 sports business when it was launched to the general public in 2003.

It appealed to competitive and leisure riders by providing the ideal balance of rider comfort, uncompromising power, and great aesthetics in a single package. The Suzuki DRZ 400, a well-known dual-purpose motorbike, provided the LTZ 400's engine on loan.

The engine is a 398-cm3, 4-stroke, liquid-cooled DOHC engine with a counter-balancer that provides valuable power throughout the powerband and enhanced torque in the reduced RPM ranges.

The ECU for the LTZ400 was designed to, among other things, choose the best injection volume, timing, and ignition depending on the engine's RPM and clutch position. Data obtained from this technology consequently helped the car's traction and ease of starting.

The engine and all other electrical equipment are powered by a triple-phase generator and a reliability CDI system. Its rear and front LTZ 400 tires were 22 inches and 20 inches in size, respectively, and they were installed on aluminum alloy wheels. On the other hand, the quad can stop the vehicle effectively with just two hydraulic front discs and one hydraulic rear disc.

Final Thoughts

Years have passed since the Suzuki LTZ 400 ruled. Even yet, this four-wheeler is still regarded as being among the best sport quads ever created. Many expert engineers and racing designers have been motivated by this mid-sized racer to create quality parts that will reveal their full potential. The QuadSport changed the sport ATV market and is still doing so today.