super Utv - transworks Mini Diff Transaxle - Photo 15215753

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The transverse mounted RC51 engine is coupled to a single speed Transworks Mini-Diff transaxle that includes a reverse gear. Independent axle outputs run through 930 CV joints out to each Gear One wheel hub that spins inside a custom fabricated trailing arm.

The car meets SCORE Class 18 and Best in the Desert Class 19 specs with its motorcycle engine and scale size. Starting from scratch allowed John and the builders to choose each component on the car to fit their needs as best as possible.

Sitting under the Polaris hood you'll find a duet of King coilover shocks and between them sits a Gear One rack and pinion box to handle directional chores. A Unisteer electric assist unit under the dash also helps ease the steering wheel effort for the driver.

Here's a top down view of the front suspension components. All the arm components were fabricated from DOM tubing. The lower end of each shock connects inside the lower arm and front skid plates protect them from rocks and other debris. Front travel capability is 22 inches.

The front spindles are custom fabricated pieces. Upper and lower A-arms mate to the spindle which rotates and pivots on horizontally oriented rod ends all captured in double shear for strength. The steering rod can be seen here as well and uses another rod end as a pivot point.

The rear suspension consists of more King hydraulics. A regular coilover shock works in tandem with an external bypass shock at each rear corner. Rear travel on the car is 19 inches.

Here you can see the Honda RC51 motorcycle engine tucked up in the middle of the chassis. This is a 999cc engine that came on Honda RVT1000R cycles from 2000 to 2006. Its design is a V-twin engine having a dual overhead cam with two fuel injectors and four valves per cylinder. In stock form, the motor produces about 130 hp, but F2 Racing has tweaked it slightly to add just a bit more punch. A Tilton pump along with a B&M plate cooler work to keep engine oil temps sane during heated runs.

Tucked within the rear trailing arms are Gear One axle shafts with 930 type CV joints under the cover of rubber boots. Wilwood aluminum calipers clamp down on large Gear One rotors when it's time to haul this buggy down from speed.

The transverse mounted RC51 engine is coupled to a single speed Transworks Mini-Diff transaxle that includes a reverse gear. Independent axle outputs run through 930 CV joints out to each Gear One wheel hub that spins inside a custom fabricated trailing arm.

The car uses two electrical systems. The original RC51 system is used with its stock alternator and a motorcycle battery to start the engine and run its functions. A standard auto size Optima rides in the passenger foot well and powers most of the other electrical requirements on the buggy. It is charged from an alternator powered at the rear axle. Two belts are used along with tensioners and an idler shaft. The pulleys are sized such that the speed of the alternator is increased due to being driveaxle driven instead of engine driven, where belt speeds would normally be faster.

The Yamaha Rhino hood hints at some UTV roots, but this car uses little from those factory built side-by-sides.

A front tube snout protects the front suspension and steering and supports a set of Sol Tek lights, one being a flood lamp and the other a long-range lamp.

More lighting resides up top. A rack with four Sol Tek HID lamps sits on the forward roof line with an aiming adjustment setup and protective cage loop above.

The mid-to-tail section of the car is a busy place. The motor and drivetrain reside below. Up top sits the Ron Davis aluminum radiator with electric fan, a 15-gallon Fuel Safe cell, a spare tire, and jack. The rear shocks are also snuggled just inside the rear quarter panels behind the seats.

A pair of BS Sand race suspension seats combined with Crow five-point harnesses keep the occupants secure in the cage. The engine's air filter is routed up and forward into the cab area to pull in reasonably clean air during a dusty race. A Parker Pumper also supplies filtered air to the racer's helmets to reduce the choke factor on the course.

Current tires are General Grabber ATs in a 215/75R15 size. The team is looking at swapping over to a MT version tire and might consider increasing size a step or two. Walker Evans 15x9 beadlocks keep the tires in place and are bolted to Gear One wheel hubs front and rear.

We caught John and co-driver Bryan Slaughter getting ready to start the BITD Vegas-to-Reno race. The car was set to run well, but some poor luck and multiple tire failure issues cut their race day short.

The interior is very much race business attire. The RC51 motorcycle electronic gauge/speedo unit is retained and mounted to the dash below direct sight of the driver. Autometer gauges poised in the center of the dash help keep a watchful eye on the cars vital signs. The motorcycle foot shifter has been translated to a hand controlled rod that exits above the center tunnel. Finally, a Lowrance GPS unit helps the co-driver stay on course along with an Icom race radio to keep in communication with pit/chase crews.