XRAY raised the bar in the 1/10 buggy class with the XB4, bringing a new high-quality, high-performance player to the field for all others to measure themselves against. Now with a more adaptive platform, XRAY’s 1/10 buggy… the new XB4’16… is now even more the beast to beat.
Dipl. Eng. Juraj Hudy
XRAY XB4 designer
The new XB4 is artistically crafted in our in-house XRAY factory by design & production specialists, and then extensively tested and refined by the world's best drivers. Designed, developed, and fully manufactured in Slovakia, Europe, with XRAY's legendary attention to detail, fine materials, and extreme performance, I am excited to present to you the all-new XB4.
Dipl. Eng. Juraj Hudy
XRAY XB4 designer
Development of the XB4 platform continues as we move into future, fueled by our fundamental belief in precision design and a desire to bring forth only the best products and world-class support. Race results from XB4 drivers around the world – including the European Champion title and dozens of national titles worldwide – prove we are on the right track.
“Being part of the R&D team, I know how much time, energy, and effort is put into further developing of all cars. Chasing perfection is a never-ending process, and as such we strive to bring you an improved and better-handling XB4. I am certain you will be amazed by the handling and reliability improvements of the new XB4’16 which will help bring you to the Winner’s Circle”
XRAY Factory Team driver
The XB4 is a typical XRAY car – a premium, professional, high competition model racing car for the most demanding racers, developed and designed with attention to the smallest details. Manufactured from premium European materials, machined using state of the art Swiss and German machines and backed by premium service & support, the XB4 is a typical XRAY, a luxury masterpiece.
The 2016 chassis is an all-new shortened design, with better weight balance and more in-front motor position, optimized design for short-pack battery only, and extra central diff mounting holes for further weight-balance adjustment.
CNC-machined from high-quality Swiss 2mm 7075 T6 aluminum, the chassis is strategically machined in low-stress areas to make it as light as possible without affecting strength or rigidity.
Weight distribution, chassis width & length, and proper flex have key influences on the handling of the car. All of these features were incorporated into the design of the chassis.
For increased lifespan, the chassis is black coated at XRAY’s own in-house fully robotic operated coating line.
Redesigned side guards accommodate the new chassis design. Moulded from a hard composite material, the side guards make the chassis frame flex suitable for the majority of track conditions. For very-low-traction tracks, optional medium stiffness side guards are available.
The tough composite side guards perfectly fit the chassis to seal against dirt and protect from side impacts.
Front & rear bulkheads were strongly reinforced in numerous areas to withstand rigorous impacts and abusive racing conditions. The diameter of the holes for ball-bearings were refined to minimize ball-bearing play, resulting in increased gear teeth lifespan and minimized gear stripping.
XRAY’s attention to the small details, R&D and engineering are obvious in the design of the diff bulkheads. These unique bulkheads allow super-fast and easy diff exchange and servicing by dismounting only 4 screws from the front of the bulkhead and bottom of the chassis. This super-fast diff access is available in both front and rear.
Multi-Flex of the XB4 is all-new and redesigned. To allow for easier flex adjustment and a wider and more optimized adjustment, gone are the long top decks which are replaced by independent upper decks; flex adjustment was transferred into the composite chassis braces and side guards.
XRAY Multi-Flex Technology™ has resulted in some of the most significant milestones in RC model car development in the last decade. This innovation has proven to be a distinct competitive advantage at tracks worldwide, helping XRAY cars dominate races at local and national levels.
The XB4 is the world’s first 1/10 off-road chassis incorporating Multi-Flex™ adjustment technology, allowing drivers to tune chassis flex for different track conditions. Whether the track is low, medium, or super-high traction, you can easily adjust the chassis flex to suit track conditions in a matter of seconds. It has never been so easy to professionally & predictably set up flex… another smart innovation by XRAY.
Long top decks are no more. The XB4 features separate front, central and rear upper decks which are independent from chassis flex adjustment and work only as part of the front, central, and rear diff assemblies.
All upper decks are machined from high-grade graphite.
In line with the all-new Multi Flex™ design, composite chassis braces replace the long upper top decks and are mounted directly to the chassis to fine-tune chassis flex adjustment. Adding or removing screws from the bottom of the chassis braces adjusts the chassis flex. The front chassis brace includes a graphite stiffener which is additionally mounted to the composite brace to hold the electronic cables… and which is also part of the chassis flex adjustment. A rear graphite stiffener is available as an option.
To accommodate the new Multi-Flex™ and upper deck design, the motor mount was redesigned as well. To allow adjustment of the weight balance, the motor mount can be easily installed frontwards or rearwards.
The graphite central upper deck holds ball-bearings in the motor mount and bulkhead assembly, while the upper deck allows easy access for slipper clutch adjustment. With the new weight-balance adjustment feature based on the motor mount position, the central bulkhead can also be mounted either frontwards or rearwards.
Power from the motor is transferred to the drivetrain via an adjustable central slipper clutch for quick & easy tuning. The all-new improved 3-pad slipper clutch ensures smoother clutch operation and more efficient braking, and clutch adjustment is easier, more consistent, and ultra-fine.
The lightweight slipper clutch plates have a machined relief which decreases the friction surface to assist with clutch slip adjustment. With this plate design, pressure is on the circumference of the clutch pads for increased efficiency.
The slipper clutch pads are made from ultra-efficient SLS material with very high slip efficiency, thus allowing very precise slip adjustment.
The clutch outdrives are super lightweight and manufactured from HUDY Spring Steel™ and then additionally hardened for extra lifespan and reliability. The slipper plates are machined from premium Swiss 7075 T6 and additionally hardened then given a black final surface treatment.
With the new redesigned chassis and weight balance adjustment, the central drive shafts were redesigned in length. Depending on the motor position, the center diff block moves as well and appropriate length central drive shafts must be chosen.
The XB4 constant velocity drives (CVDs) are manufactured from world-renowned HUDY Spring Steel™. The drive shafts are some of the world‘s thinnest yet most durable drive shafts used in electric off-road cars. Hardened with a proprietary hardening process, the drive shafts provide unbeatable lifetime and reliability.
Both front & rear lower arms are new in the XB4. The front arms are narrower which allow them to be moved frontwards and rearwards to adjust weight balance. With the new design of the front arms, the weight of the car is moved more towards the center of the car.
The rear arms feature a more reinforced design to better withstand crashes. Both front & rear arms have new more optimized shock position mounting holes which are suitable for all track conditions.
Suspension arms are one of the most important parts of any RC model car, as they directly influence the handling characteristics of the car. The XB4 suspension arms are the result of long-term tests of different designs and layouts. Length, thickness, flexibility, geometry, and materials used… these are all part of the concepts & details that are thoroughly reviewed to create optimum suspension arms.
The exclusive composite mixture used for suspension arms is a perfect balance between reliability and performance. The suspension arm itself is rigid enough to provide a responsive feel, yet soft enough for extreme durability.
Uprights were redesigned with new lower roll center position which moves the uprights more outside of the car for increased stability.
The upper roll center adjustment has 3 different positions. The rear uprights feature 0° toe to ensure stability and prevent suspension geometry changes in hard crashes. The very compact uprights are small in size but very strong due to the special composite mixture used.
For maximum drivetrain reliability, larger 5x12 ball-bearings are used in the outer position for increased dynamic load. On the inner position, the smaller 5x10 ball-bearings are used to minimize unsprung weight.
The outer suspension pin on which the rear upright sits features shims for additional wheelbase adjustment.
Shock towers were redesigned to accommodate the new reinforced bulkheads. These new shock towers feature new more optimized shock positions which correspond to new upper arm shock positions.
Both front & rear shock towers are machined from premium-grade graphite, are lightweight and strong, and have multiple shock positions as well as multiple roll center adjustment positions. The rear shock tower holds the wing mount.
A very handy, compact electronics plate allows for mounting the speed controller for quick & easy removal and assembly, and was redesigned to fit the new chassis and side guards.
With the new weight balance adjustment, the new XB4 features two different battery straps: short -or- long. Using the new longer battery strap, the battery pack can be installed either frontwards or rearwards; included foam back spacer ensure the battery pack will not fall out.
The new front body post is shorter to fit the new front upper deck and body.
Beefy 6mm thick body posts are made from special composite material for maximum strength. The body supports are rounded to have a better fit and provide better support for the car body.
The all-new XB4 body features high-downforce areas (including front window and top roof flow channels) for proper air flow, and side downforce areas and top central rib for higher stability. The high-performance, low-profile aerodynamic body was designed by XRAY to perfectly fit the XB4 and work in most track conditions. The body is made from high-quality premium Lexan™ material.
For very-high-traction track conditions, an optional ultra-lightweight body is available that will reduce the roll of the car and improve rotation of the car in corners.
With the all-new design you can easily adjust the weight balance. You can move the motor frontwards and rearwards, and you can do this independently of the short battery pack that can be moved frontwards and rearwards as well.
The XB4 is a conventional shaft-driven 4WD off-road car featuring:
The internal ratio of the drive train is 1:2.5
XB4 constant velocity drives (CVDs) are manufactured from world-renowned HUDY Spring Steel™. The drive shafts are some of the world‘s thinnest yet most durable drive shafts used in electric off-road cars.
Hardened with a proprietary hardening process, the drive shafts provide unbeatable lifespan and reliability.
The CVD assembly also features a composite safety collar to keep the mounting pin solidly in place.
The XB4 gear diff ensures increased on-power steering which is needed on nearly all types of tracks, and is ideal for both carpet and clay tracks.
The super-smooth gear diff includes a composite case and cover with integrated crown gear. The internal gears are precision-molded from tough XRAY developed and mixed composite material ensuring high life time and super-smooth and efficient operation.
The maintenance-free diff design is a feature that will benefit racers of all levels. When the diff is correctly built, there is no need for maintenance for a very long time… no need for frequent oil changes, and no leakage due to our superior sealing system.
Both front & rear diff crown gears and pinion gears are made from steel which has been additionally hardened to ensure increased lifespan and reliability. The width of the crown gear teeth is narrower to allow the gear to be as light as possible. The width of the pinion gear teeth is wider to allow it to work also with optional composite and aluminum crown gears.
For clay and low-traction tracks, optional graphite diff crown gears can be used to increase traction.
The optional ball differential was designed and is suggested for low traction track conditions. Externally adjustable ball differential is machined from HUDY Spring Steel™ and additionally hardened for extra durability and long lifetime. High-quality carbide thrustbearing is included for smooth operation and the carbide balls ensure ultra-smooth running. The ball differential comes factory pre-assembled.
A central differential is recommended for use on clay and low-traction tracks to increase traction.
The super-smooth gear diff includes a composite case and cover with exchangeable spur gear. The gear diff set includes 81T spur gear and a range of various spur gears is available as an option.
The maintenance-free diff design will benefit racers of all levels. When the diff is correctly built, there is no need for maintenance for a very long time… no need for frequent oil changes, and no leakage due to our superior sealing system.
To reduce rotating weight, the super-lightweight diff outdrives are machined from HUDY Spring Steel™ material which allows additional material to be removed on the outer part of the outdrives, further reducing the weight without effecting durability. The inner part of the outdrives is additionally hand-ground for perfect fitment into the diff case.
The outdrives are hardened using XRAY’s own special hardening process to provide extended lifespan and reliability.
Precision-molded spur gears are made from XRAY's exclusive secret blend of composite material, allowing the gear to run true yet be robust enough to handle high-performance brushless motors. The spur gears are designed to have the lowest possible weight while staying strong and light. Each gear is stamped with the tooth number for easy identification.
The XB4 is equipped with an 81T spur gear which suits the majority of tracks. For additional tuning, optional 75T, 78T, and 84T spur gears are available.
The motor is connected to an eccentric mounting plate, with the assembly then inserted into an integrated motor holder/drivetrain support. The design allows quick & easy motor rotation to adjust gear mesh, and yet clamp securely using only a single screw.
To ensure the motor will not loosen in a serious crash or due to insufficient tightening, the motor plate has a bayonet mounting system which prevents it from being dislodged from the motor holder. By rotating the motor mount plate to the opposite direction, the motor can be quickly removed from the motor holder.
Removing the motor or adjusting the gear mesh is easy and fast, with changes possible in only a few seconds.
The correct suspension geometry is one of the most important features of any RC model car, while at the same time being one of the most difficult and challenging features for a designer.
The suspension is always a mixture of:
From the suspension arms, through the suspension blocks, to the light yet robust steering blocks, every suspension part has been specially designed for the 1/10 off-road racing platform to provide responsive racing characteristics in all conditions.
Over the years, XRAY has successfully gained and utilized extensive knowledge of suspension geometry and stiffness, which has been applied while designing suspension parts. The ultra-lightweight suspension parts are molded from a special composite material to make the parts very light yet very durable to withstand the rigors of high-performance racing.
The front and rear arms feature double shock mounting positions and integrated anti-roll bar mounts.
The aluminum suspension holders feature Integrated Suspension Settings (I.S.S.™) which allows for super-fast & easy suspension geometry setting. This XRAY concept was first introduced in the very first XB8 and now has been carried over to the 1/10 scale XB4.
Using eccentric suspension bushings – which are inserted into aluminum suspension blocks – as well as additional shims, the XB4 suspension geometry can be completely adjusted including:
A complete set of eccentric bushings is included for complete suspension geometry adjustment. The bushings are inserted into aluminum holders which are machined from premium Swiss 7075 T6.
Suspension arms allow for quick & easy wheelbase adjustment. Using included 2mm shims, both front and rear suspension arms can be moved either forward or rearward to adjust weight balance depending on track conditions. By moving the arms to the front, the balance and weight of the car are transferred more to the rear; this is recommended for medium- and high-traction conditions. By moving the arms to the rear, the balance and weight of the car are transferred more to the front.
The wheelbase shims allow not only forward/rearward suspension positioning, but also allow the wheelbase to be adjusted shorter or longer to fine-tune set-up for various track conditions.
The 1-piece caster blocks are very lightweight, yet the construction of the caster blocks makes them very stiff and rigid. The non-adjustable caster angle is preset for 9°. The roll center position can be easily and quickly adjusted by inserting different thickness of shims on the top of the caster block between the block and the vertical ball stud.
The caster blocks feature large openings for quick & easy assembly/disassembly of the CVDs. The entire CVD assembly can be easily inserted/removed through the C-hub without the need for disassembly. The large openings also prevent collision of the CVD with the C-hub in serious crashes.
The front of the chassis is pre-angled with an integrated 8° caster angle, however the position of the adjustable eccentric bushings in the I.S.S. suspension holders influence the caster as well. (For example, if the eccentric bushings have the roll center in middle position, the caster angle is 9° and with the 9° in caster block the overall caster angle is 18° of caster.
The total adjustable caster range in the kit is 16-20°.)
Optional caster blocks with 6° and 12° caster angles are available for further suspension geometry adjustment.
The tiny yet tough steering blocks are molded from a special composite mixture for maximum strength.
Composite steering block inserts allow for very quick & easy lower roll center adjustment. With additional shims and extra inserts, fine tuning the roll center is easily achieved.
For maximum drivetrain reliability, larger 5x12 ball-bearings are used in the outer position with increased dynamic load. On the inner position, the smaller 5x10 ball-bearings are used for minimized unsprung weight.
Ultra-lightweight 14mm wheel hex drive hubs are CNC-machined from Swiss 7075 T6 black-coated aluminum. These ultra-true hex hubs have a clamping design which ensures ultra- solid mounting of the wheel on the hub.
The alu hex hubs are specially machined to reduce rotating weight while guaranteeing wobble-free wheel mounting.
To adjust the track-width, optional offsets are available.
The dual arm steering system is very simple yet effective and features an integrated easily adjustable servo saver. Ackermann is easily adjusted by quickly & easily changing the steering link mounting positions on the steering plate.
Bump steer is easily adjusted for more aggression by inserting a shim between the steering block and steering linkage.
To guarantee maximum reliability, all turnbuckles are manufactured from special HUDY Spring Steel™ material for turnbuckles which features a tougher core. These turnbuckles are used for front & rear upright linkages, steering system, and also for the servo saver.
Well-built, reliable shock absorbers are extremely important for super-smooth suspension action on every type of track. The shocks on the XB4 have been specifically designed to be built easily, perform consistently, and last reliably. Attention was paid to all the smallest details during the design process, as well as during the long-term testing in various conditions and track types.
The big-bore shocks are membrane free, but still allow for easy, consistent building and rebound setting using the bleed-screw shock cap design.
The up-stop travel of shock rod is adjusted via rubber O-rings, while the downstop is adjusted using composite shims under the pistons.
The aluminum body, lower nut, and bleeder shock caps are all machined from premium Swiss 7075 T6.
The pistons are made from Delrin® and are molded using super-precise moulds. There are several types of pistons included with different holes and diameters for precise shock adjustments. For custom adjustment, a set of blank non-drilled pistons are also included.
The shock rods are machined from special steel material, precision hand-ground for maximum smooth operation and additionally hardened for increased lifespan.
The XB4 springs have been specifically designed to complement the big-bore shocks.
The XB4 springs, like all other XRAY springs, are manually measured, selected, and matched into pairs to guarantee precisely equal length and damping characteristics.
Each of the springs is laser engraved with stripes to indicate the firmness of the spring; the more strips, the harder the spring.
The new design of the rear suspension arm allows very practical variable position of the rear shock absorbers. Depending on track conditions, the rear shock absorbers can be installed either in front or behind the shock tower.
XRAY Premium Silicone Oils are manufactured in Europe by a specialized premium silicone oil manufacturer; these new oils were exclusively created for XRAY. Each batch of premium oil is laboratory tested and calibrated to ensure the highest possible consistency and quality from one batch to the next. Based on the industry-standard cSt rating, the new line of oils will be easy to identify, adjust, and feel.
When following any set-up sheets by XRAY or XRAY team drivers, you can be sure that the oils you get for your car will be exactly same oil as used by the factory racing team, thus ensuring very reproducible set-ups and handling.
Anti-roll bars are manufactured from special spring steel material and are included to stabilize the front & rear ends of the car. The roll bars are easily mounted to the diff cases and can be adjusted with the linkages.
Both front & rear anti-roll bars are interchangeable since they have same design and shape. The thickness of each anti-roll bar is laser-engraved for easy identification. Anti-roll bar wires of different thickness are optionally available for fine-tuning.
A full set of 22 high-speed, blue-sealed ball-bearings are used throughout the drivetrain to ensure maximum efficiency. All of the bearings are degreased and oiled with Aero Shell® Fluid 12 for maximum smoothness and long life.
Stylish and effective rear wing was designed to work perfectly with the XRAY XB4 body. Made from strong Lexan™ material, the wing is supported on the wing mounts by extra flat shims to better support and extend the life of the wing.
Optional thicker 1.5mm (#363511) and 2.0mm (#363512) rear wings are highly reliable with less chance of breakage, while at the same time influencing the performance of the car as well. The thicker wing gives higher traction and stability, but gives reduced steering.
The new specially-designed XB4 wheels are perfect for high-competition racing. The wheels are made from a very flexible material, while still being durable to withstand impacts. The side of the wheel is aerodynamic for maximum performance.
The special features of the wheel are visible from the inside – the reinforcement ribs are designed to make the wheels as stable as possible and eliminate deformation. The front wheels feature +1mm offset which makes the front of the car wider and therefore more stable.
The chassis design focuses on balanced weight distribution and weight transfer. The chassis features pre-drilled holes for additional weights for optimum car balancing. Centerline holes are pre-drilled for easy balancing with the HUDY Chassis Balancing Tool #107880.
The extensive and impressive range of adjustment possibilities includes: caster, camber, toe, kick-up, anti-squat, ride height, downstops, track-width, lower roll center, upper roll center, roll center positions, bump steer, wheelbase, Ackermann, adjustable shocks, adjustable front and rear diff and adjustable XRAY Multi-Flex™.
The XB4 includes premium HUDY Graphite Grease which is a high-performance, advanced-technology semi-fluid lubricant which incorporates both extreme pressure additives and finely-dispersed graphite for load carrying. It is intended primarily for the lubrication of rotating parts and loaded gears. In addition to providing outstanding load carrying, it is formulated to have excellent adhesion and resistance to "fling-off" under extreme conditions. The grease reduces wear and increases parts life.
The XB4 is one of the most adjustable electric off-road car in the world. Whether you are a hardcore racing fanatic or a club-level sportsman, you can very easily adjust the XB4 to suit your racing style, race track type, and all track conditions. To fully understand the set-up possibilities we recommend the legendary HUDY Set-up Book, loaded with over 40 pages of high-quality pictures and easy-to-understand RC car set-up explanations. Whether you are a novice driver or experienced racer, you can easily learn many set-up tips & tricks and improve your set-up skills, ultimately translating into improved racing performance with your XB4. The HUDY Set-up Book is available for download exclusively at www.hudy.net
XRAY Instruction Manuals have become the industry standard, being simply the best manuals you will ever get with an RC model car. Whether you are a first-time builder or an experienced racer, all the instructions are straight-forward and easy to understand. The full-color instruction manual contains large 3D illustrations that show all assembly details in the clearest possible way.
Owning an XRAY model racing car is an experience on its own. Not only will you own the most premium luxury model racing car in the world, but you will also become a member of the prestigious family of XRAY owners with direct support and service from the XRAY factory. XRAY brings you the most up-to-date RC Web site on the Internet, with daily racing news and latest product developments. If you have any questions, problems or comments, you can ask the XRAY Support Team or any XRAY Factory Team Driver on the XRAY Support Forum. You can even upload your own set-up sheets or download from the thousands of different set-up sheets available from all around the world at the exclusive XRAY Virtual Set-up Sheet Database, the world’s largest set-up sheet database. And that is only the start of the VIP treatment you get by joining Team XRAY.