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Inferno MP-7.5 Y.K2 4wd 1/8

IN THE WORLD OF 1/8-SCALE BUGGIES, the Kyosho Inferno series is legendary, thanks to its six consecutive IFMAR World Championship titles. The original Inferno spawned the MP-5, MP-6 and the most successful of all the Infernos-the MP-7.5. Yuichi Kanai is the designer of the world champion 7.5, and in 2000, Yuichi actually won the title with the car he designed. To commemorate the win, Kyosho released a "Kanai Edition" MP-7.5. The signature model evolved into the Kanai II (which Greg Oegani drove to victory at the 2002 IFMAR Worlds), and for the 2004 event, Yuichi has further honed the big buggy into the Inferno MP-7.5 Yuichi Kanai Edition III. With less weight, greater durability and increased suspension travel, the Kanai III is the ultimate Inferno and just may be the best buggy on the planet; we'll find out in August at the 2004 Worlds in San Paolo, Brazil. But you'll only have to wait as long as it takes to turn the page to get under the hood of the Kanai III.

CHASSIS. The Kanai III chassis is 3mm 7075 hard-anodized aluminum, which is as tough as 1/8-scale buggy chassis get. Like all MP-7.5S, the chassis has "blisters" punched into its underside that allow the differentials to sit a millimeter or so lower than they otherwise could, but unlike other MP-7.5S, the top of the Kanai III chassis is strategically milled to shave off precious grams; according to Kyosho, 1.4 ounces (40 grams) has been pared thanks to the process. A few more grams are trimmed by the liberal use of titanium hardware; more than half the kit's screws are made of everyone's favorite wonder metal.

The rest of the chassis features are standard MP-7.5 stuff. The radio box has separate receiver and battery compartments, the 2mm radio tray is secured by turned-aluminum standoffs, and rod braces bolster the gearbox/suspension assemblies.

DRIVE TRAIN. Kyosho's Traction Control Differential (TCD) has been a staple of the Kanai series and returns with the III model. Unlike the Kanai II, which had TCDs front and center, the Kanai III only uses the TCD up front. The diff uses steel reinforcement plates to prevent the four, fine-pitch, hardened-steel spider gears from separating under load. The center and rear diffs use cast-alloy gear sets with coarser teeth. All three diffs are sealed, of course, so their action can be adjusted by varying diff-fluid viscosity, and the center diffs spur gear is steel. Universal-joint drive shafts join the diffs and connect the differentials to the stub axles.

Interestingly, the Kanai III does not have a fashionable 4-rotor brake system. A pair of vented-steel rotors that are squeezed by padded calipers do all the work, and its stiff brake springs don't have to be exchanged for sections of fuel tubing. The springs are a small touch but one that greatly increases brake feel and power. Each brake linkage is threaded, and adjustable via a knurled thumbwheel, so you can alter brake bias.

ENGINE AND ACCESSORIES. You won't find an engine or exhaust system in the Kanai III's box, but you will find everything you need to install them. A 3-shoe clutch with a lightweight flywheel is supplied and uses the usual mousetrap-style springs, but the shoes are made of aluminum, so they engage "harder" and wear longer. The engine mounts are machined aluminum and deeply finned to increase cooling; and they're attached to the chassis with plates that allow you to remove and reinstall the engine without altering the gear mesh. Fuel is supplied by a standard MP-7.5 tank with the usual features: internal stone filter, molded-in spillway and cap-mounted pressure tap. An ample splashguard alongside the tank keeps fuel away from the brake system and clutch bearings during fast fill-ups.

SUSPENSION AND STEERING. The Kanai III's shocks look like standard MP-7-5 units, but the rears are 2mm longer. That might not sound like much, but an extra 2mm at the shock eyelets translates into significantly more downtravel at the axles. The Kanai III's suspension verges on monster truck territory, so bumpy tracks shouldn't be a problem. Length notwithstanding, the shocks are standard Inferno stuff: aluminum bodies, heavy-duty 3.5mm shafts, bladder volume compensators, clip-on preload spacers and shaft-protecting rubber boots. The only uncool parts are the pins that hold the lower shock eyelets; they love to vibrate out. I'll replace them with screws later.

Along with extra travel, the Kanai III's suspension gets some extra adjustability. The kit includes two sets of front upper arms and hub carriers that let you select 20 or 22 degrees of caster, and the steering plate now has three holes for a greater range of Ackerman settings. New, heavy-duty, titanium-nitride-coated steel turnbuckles set camber and toe-in. Swaybars are standard (2.5mm front, 2.8mm rear), and the inboard hinge pins are held by 3mm aluminum plates behind the front gearbox on a machined-aluminum block, so they'll stay put in a crash.

BODY. WHEELS AND TIRES. Make that "body and wheels," since the kit doesn't include tires. The body is a standard MP-7.5 shell, but for Kanai III duty, precut Lexan reinforcements are provided to strengthen the area around the body posts. The wheels are standard Inferno 10-spokers in Kanai's trademark green, which is also the color of choice for the bi-level rear wing. Thick arms braced by aluminum standoffs hold the wing, and there are two wing-angle settings.