R/C CAR STAFF

Kyosho’s new Lazer ZX-5 FS is the third version of the buggy that reintroduced Kyosho to the ranks of 4WD electric off-road racing nearly five years ago. The car’s suspension was changed when the SP update was released, and the handling changes made to the ZX-5 platform vaulted the car into the limelight with worldwide racing success, along with the top award in R/C Car’s 4WD Shootout (July ’08). Just in time for the ’09 racing season, Kyosho has once again fine-tuned the Lazer with the new FS version, which features several dramatic changes over the SP that we know and love. Let’s get down to the nitty gritty and see if the changes were for the better.

KIT FEATURES
All stretched out: The composite tub chassis on the FS is a full 10mm longer than the SP for more reaction and rough-track stability. Additionally, the new chassis positions the motor and slipper sparkles as far forward as possible, while reserving the rear of the chassis for a saddle pack-style battery. Speaking of the saddle pack, the body clip-restrained battery bars offer two different options to move the battery fore and aft.

Fully suspended: Great news comes at all four corners of the FS, as the same suspension layout found on the SP is used on both ends of the new 4WD racer. The suspension geometry was the largest change from the original ZX-5 to the SP, as the front knuckles, hubs and suspension arms, along with several changes to the rear end, were changed to correct the car’s track handling capabilities. However, the rear shock tower is reversed from the SP to allow the rear shocks, the same velvet-coated, threaded-body coilovers found on the other Lazers, to be mounted on the front side of the rear arms to further move the buggy’s weight distribution forward.

Drive train: The new chassis layout mandates that the motor shaft extends towards the front of the car, which is opposite of the SP version. Because this means the motor rotates in the opposite direction in relation to the car, the FS chassis moves the motor to the left side of the chassis so that the motor’s rotation cancels out the rotation of the center driveshaft to help eliminate torque steer. A two-disc slipper clutch runs inline with the center driveshaft, which then spins ball differentials at each end of the car. CV-style driveshafts are used to spin each wheel.

All the right toppings: The wheels on the FS have been changed aesthetically from its predecessors, no longer featuring the ridge that ran around the outside of the wheel. The FS body retains the design cues of the low-slung SP body but has been lengthened to match the longer chassis, and the new wing features a low front scoop to funnel air toward the large wicker bill which can be trimmed to the racer’s preference.