Designed, developed, and fully manufactured in-house at the XRAY factory in Slovakia, Europe, using the most high-tech German and Swiss machines and premium European materials, crafted with XRAY's trademark attention to detail by our production specialists. The X4 is truly a masterpiece.
X4F is designed and based on the X4 platform and as such majority of all parts are fully compatible.
The unique CFF™ upper & lower suspension arms are an elegant engineering achievement that look great and perform even better on the track. Using XRAY’s own newly developed manufacturing process, a carbon fiber arm and composite arm are molded together using a fusion process to produce a single CFF™ suspension arm.
The benefits of the CFF™ arms are tremendous. The thickness of the inner carbon fiber plate determines the hardness and flex of the arm. The composite around the carbon helps control its flex and rebound, resulting in a very consistent feel from corner to corner.
Medium and hard versions are available to tune the X4F handling to different track conditions.
The unique CFF™ upper & lower suspension arms are an elegant engineering achievement that look great and perform even better on the track. Using XRAY’s own newly developed manufacturing process, a carbon fiber arm and composite arm are molded together using a fusion process to produce a single CFF™ suspension arm.
The benefits of the CFF™ arms are tremendous. The thickness of the inner carbon fiber plate determines the hardness and flex of the arm. The composite around the carbon helps control its flex and rebound, resulting in a very consistent feel from corner to corner.
Medium and hard versions are available to tune the X4F handling to different track conditions.
Thanks to the unique design of the CFF™ arms, all the suspension components are mounted directly on the arm without additional brackets, bushings or extensions. This direct mounting eliminates unwanted play between these extra components. Most importantly, the reliability and accuracy of the direct mounting ensure that settings remain consistent during a run even after a crash.
Thanks to the unique design of the CFF™ arms, all the suspension components are mounted directly on the arm without additional brackets, bushings or extensions. This direct mounting eliminates unwanted play between these extra components. Most importantly, the reliability and accuracy of the direct mounting ensure that settings remain consistent during a run even after a crash.
This direct mounting eliminates unwanted play between these extra components. Most importantly, the reliability and accuracy of the direct mounting ensure that settings remain consistent during a run even after a crash.
The CFF arms create a calm and stable feel on the track while remaining extremely sharp and responsive. The new suspension creates great traction, improves cornering speed, and provides quick reactions to driver input. The result is greater driver confidence that is critical for improved lap times. (*X4 photo shown)
The CFF arms create a calm and stable feel on the track while remaining extremely sharp and responsive. The new suspension creates great traction, improves cornering speed, and provides quick reactions to driver input. The result is greater driver confidence that is critical for improved lap times.
The X4F chassis is designed for the new CFF™ suspension concept and adds alignment holes for the centering pins found on all of the X4F bulkheads and motor mount for maximum reliability in a crash.
The X4F chassis is designed for the new CFF™ suspension arms that are mounted via pivot balls directly to the chassis.
The X4F chassis works together with the new motor mount and bulkheads using alignment holes for the centering pins on each of the mounted components. Thanks to the centering pins, the assembly of structural components is hassle free, and most importantly the parts resist movement in a crash to let you finish the race without losing pace.
The narrower design of the chassis together with the perfectly symmetrical shape provide optimal flex characteristics.
Super-strong one-piece motor mount is placed in the absolute chassis center and features integrated layshaft axle and new tweak-free top deck mounting.
The X4F motor and layshaft mounts are integrated into a one-piece design that is placed on the absolute center line of the chassis. The new motor mount has a pressed-in steel layshaft axle with the motor located to the front of the layshaft. The motor mount is designed to maintain a super low CG but is still robust enough to resist bending in serious crashes. The robust design reinforces the chassis and improves the stability of the X4F.
The top of the motor mount features special milled holes to match the machined ultra-precise top deck screws made in-house. These purpose-made screws ensure the top deck is mounted completely tweak-free to improve the flex characteristics.
An aluminum eccentric bulkhead insert is accessible through a cutout in the mount and is adjusted from the top for easier gear mesh adjustment.
Positioned closer to the front of the X4F, the new motor mount location creates a better F/R weight balance.
The lower part of the motor mount features machined centering pins that are inserted in the chassis for easy assembly and to ensure it does not shift in a crash.
Machined from premium Swiss 7075 T6 aluminum and black anodized.
Integrated battery backstops set the battery position to adjust weight balance and prevent interference with the spur gear.
Serving a dual purpose, the new aluminum washer secures the layshaft to the motor mount and functions as a backstop to prevent battery pack movement. An additional backstops are mounted directly to the chassis.
The battery backstops prevent the batteries from moving in a crash and interfering with the spur gear on the center layshaft.
The X4F moves the servo to a new position. For the optimal configuration to work with the popular low-profile shorty batteries in the FWD class, the servo is moved to the battery side of the chassis. The servo mount is placed as far forward as possible with the battery located right behind the servo. Together with the new motor mount position, the X4F chassis layout provides better L/R and F/R balance with more forward bias that is desirable for maximum performance in the FWD class.
The servo mount features an additional battery holder to secure the battery pack.
The tweak-free, fully adjustable Quick Battery Mounting System offers simple and secure battery installation without tape and without adverse effects on chassis flex.
The tweak-free, fully adjustable Quick Battery Mounting System offers simple and secure battery installation without tape and without adverse effects on chassis flex.
The system controls the positioning of the pack in the chassis while at the same time reducing the battery pack’s impact on chassis flex, resulting in more consistent handling and stability.
Smart battery holders are specifically designed for LiPo batteries and are reinforced for harder impacts. The battery holders prevent the batteries from moving under racing conditions and crashes.
The front battery holder is integrated into the servo mount and allows to set the height of the battery holder by shims depending if standard shorty or low profile shorty is used. In the rear the battery holder is mounted to the chassis and is adjustable in all directions.
The super-lightweight hollow aluminum layshaft eliminates drivetrain vibration.
The all-new aluminum layshaft is strategically CNC-machined to minimize rotating weight without compromising strength or integrity. The hollow layshaft is perfectly round with zero run out, reducing drivetrain vibration.
The lay shaft is machined from premium Swiss 7075 T6 aluminum and then black coated.
The composite belt pulleys key solidly to the layshaft, and the completed assembly is installed onto the motor mount’s steel layshaft axle.
The X4F includes a 100g brass weight that is mounted under the new front lower bumper that helps to increase traction in the FWD application and makes the car easier to drive.
The X4F includes a 100g brass weight that is mounted under the new front lower bumper that helps to increase traction in the FWD application and makes the car easier to drive.
The new bumper is made from a harder and heavier material, improving durability and weight balance. The bumper is shaped with space for the front chassis weight.
With the BPA (Body Position Adjustment) system, the entire bumper area was redesigned with upper & lower composite bumpers. The foam bumper design works with the adjustable eccentric body posts as well as the standard fixed body posts.
The new heavy duty bulkheads feature centering pins for maximum reliability in a crash and raised diff positions for improved cornering speed in high traction conditions.
The X4F bulkheads have added centering pins for easier positioning on the chassis and for increased rigidity and consistency.
The X4F bulkheads are the heavy duty version from the X4 for improved crash protection.
The new bulkheads offer an upper diff position that is higher than possible on previous models for improved handling in higher traction conditions resulting in better cornering speed and steering. The anti-roll bar mounting position keeps the wire bar placed under the drive shafts for a super low CG.
The bulkheads feature milled grooves for the ball bearing hubs so the bulkheads can sit 1mm closer to the chassis center line from each side.
The bulkheads are connected by a graphite brace in front and shock tower in rear for added stiffness.
Made from premium Swiss 7075 T6 aluminum, black anodized
All chassis mounted aluminum framework parts including the bulkheads, motor mount, servo holder, front shock towers and rear body post plates feature centering pins for easy assembly and maximum reliability in a crash.
The reinforced upper clamps provide improved durability in case of a severe crash.
The screws installed from the bottom of the caster inserts capture the inserts in the upper clamps to prevent them from coming loose while servicing the car. The screws also serve as the upper arms pivot ball mounts, reducing the number of components in the assembly and reducing weight.
The upper clamps and caster inserts are made from premium Swiss 7075 T6 aluminum and black anodized.
The reinforced upper clamps provide improved durability in case of a severe crash.
The screws installed from the bottom of the caster inserts capture the inserts in the upper clamps to prevent them from coming loose while servicing the car. The screws also serve as the upper arms pivot ball mounts, reducing the number of components in the assembly and reducing weight.
The upper clamps and caster inserts are made from premium Swiss 7075 T6 aluminum and black anodized.
Aluminum inserts easily set the caster angle for quick and accurate tuning. The 2 dot inserts are included for both front and rear, with 1 and 3 dot inserts available for additional tuning options. In the rear suspension, the inserts can be reversed for even more adjustment possibilities.
The all-new Multi-Flex™ top deck has a narrow shape for easier installation, improved handling characteristics and features several different flex options out of the box.
The all-new Multi-Flex™ top deck has a narrow shape for easier installation, improved handling characteristics and features several different flex options out of the box.
The machined ultra-precise top deck screws ensure the top deck is mounted completely tweak-free to improve the flex characteristics.
Made from 2.0mm graphite material, the shape of the top deck has been specifically designed to achieve maximum traction and great steering characteristics at the same time.
Graphite composite hubs provide improved geometry for better steering and traction, fully adjustable axle height and improved driveshaft alignment.
All-new graphite composite front and rear hubs create new suspension geometry for improved steering and traction. The hubs contain new bearings and an updated drive axle that moves the driveshaft pivot point deeper into the hub, in line with the hub’s rotational axis between the upper and lower arm. This new alignment improves driveline efficiency and handling.
The new hubs allow full adjustability of the axle height to adapt the car to every condition.
The design of the hub is universal with the same part used at all four corners with corresponding extensions. The aluminum front steering plates and rear ARS plates are easily mounted depending on the hub’s location.
The ultra-narrow wheel hubs are lightened for reduced rotating mass and feature a smart axle assembly system through a simple C-clip.
The gear differential repositions the pulley for a more centered belt alignment that improves consistency and forward traction.
The front differential feature updated designs to move the belt positions closer to the center. By moving the belt closer to the center line of the car, the forward traction and efficiency is greatly improved; important benefits in the FWD class.
The gear diff includes a composite case and cover with the integrated pulley. The internal gears are precision molded from tough composite material and combined with aluminum drive shaft adapters to create a light and super-smooth differential.
Another key advantage of the gear diff is that it is virtually maintenance-free. 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 the superior sealing system.
Precision-molded spur gears are made from XRAY's exclusive composite material, ensuring true running, super-quiet operation, and robustness for handling powerful motors. A range of optional spur gears for fine tuning is available.
Precision-molded spur gears are made from XRAY's exclusive composite material, ensuring true running, super-quiet operation, and robustness for handling powerful motors. A range of optional spur gears for fine tuning is available.
The split aluminum front shock towers are mounted directly to the chassis and have adjustable flex options by adding screws to secure the towers to the bulkheads for additional stiffness.
The split aluminum front shock towers are mounted directly to the chassis and have adjustable flex options by adding screws to secure the towers to the bulkheads for additional stiffness.
All-new aluminum one-piece rear shock tower is mounted directly to the rear bulkheads and its shape provides optimized shock positions for maximum rear traction. Unlike the split front towers, the one-piece rear tower was found to provide better consistency and balance throughout testing.
All-new rear body mounting system is connected directly to the chassis and allows installation of the body posts in both the traditional vertical position and a horizontal position for a different feel on the track
The carbon fiber brackets are machined from strong 3mm thick material and are connected to the chassis via sleek aluminum mounts.
All-new rear body mounting system is connected directly to the chassis and allows installation of the body posts in horizontal position.
The carbon fiber brackets are machined from strong 3mm thick material and are connected to the chassis via sleek aluminum mounts.
The X4F steering system is redesigned for improved steering characteristics and cornering speed. The new steering plate has updated positions for the links and sits closer to the chassis. The steering posts are shorter to reduce the flex in the steering system for more precise reactions to inputs. The steering system also features a shim on the bottom of the plate for easy adjustment of the steering lock angle. The aluminum steering arms are now included as standard in each X4F kit.
The dual-arm steering system is supported by six ball-bearings and rotates on aluminum posts. Ackermann is easily adjusted by inserting shims between the steering plate and ball ends for the steering rods. The lowered position of the steering linkage gives the car improved handling going through the corners.
The X4F steering system is redesigned for improved steering characteristics and cornering speed. The new steering plate has updated positions for the links and sits closer to the chassis. The steering posts are shorter to reduce the flex in the steering system for more precise reactions to inputs. The steering system also features a shim on the bottom of the plate for easy adjustment of the steering lock angle. The aluminum steering arms are now included as standard in each X4F kit.
The dual-arm steering system is supported by six ball-bearings and rotates on aluminum posts. Ackermann is easily adjusted by inserting shims between the steering plate and ball ends for the steering rods. The lowered position of the steering linkage gives the car improved handling going through the corners.
Longer front ECS drive shafts with new drive axles move the pivot in line with the hub rotation to improve traction and efficiency.
The X4F features longer 58mm ECS drive shafts in the front ECS drive shafts have redesigned drive axles with new geometry that places the driveshaft pivot point in line with the rotation of the hubs for improved efficiency and cornering speed.
The XRAY ECS drive shafts equalize the speed between the drive shaft and the wheel when cornering. With a unique 2-piece joint between the driveshaft and the wheel, an extreme turning angle is divided into two shallower angles in the ECS assembly to prevent bind while rotating. Regardless of cornering speed and wheel angle, the inner wheel will not bind or vibrate when using the ECS. Movement through the corner is more stable and precise. With the ECS drive shafts, wheel vibrations and noise are decreased to a minimum, steering is increased, and cornering speed & smoothness are noticeably improved.
ECS drive shafts are exclusively manufactured from special self-developed HUDY Spring Steel™. The drive shafts are strategically lightened to guarantee the lowest possible weight without compromising strength or durability.
The 58mm ECS driveshafts improve performance right out of the box, increasing stability and cornering speed.
The graphite brace reduces flex in the front of the car. The brace will increase initial steering response but will reduce grip from mid corner to exit. The brace is recommended for any conditions that benefit from aggressive initial response and is more precise to drive. The brace also increases stability on bumpy tracks.
The composite front upper bumper brace prevents chassis damage in serious crashes. The brace was designed to distribute the forces from a big impact to reduce damage to the chassis plate. There are two different mounting positions depending whether the graphite brace is installed or not.
The graphite brace reduces flex in the front of the car. The brace will increase initial steering response but will reduce grip from mid corner to exit. The brace is recommended for any conditions that benefit from aggressive initial response and is more precise to drive. The brace also increases stability on bumpy tracks.
The composite front upper bumper brace prevents chassis damage in serious crashes. The brace was designed to distribute the forces from a big impact to reduce damage to the chassis plate. There are two different mounting positions depending whether the graphite brace is installed or not.
The X4F kits include progressive 2.5-2.8 springs for the front and 2.5 for the rear as the preferred starting point for most tracks.
The 4S springs - like all other XRAY springs - are manually measured, selected, and matched into pairs to guarantee precisely equal length and damping characteristics.
The X4F kits include progressive 2.5-2.8 springs for the front and 2.5 for the rear as the preferred starting point for most tracks.
The 4S springs - like all other XRAY springs - are manually measured, selected, and matched into pairs to guarantee precisely equal length and damping characteristics.
Shock bodies are CNC-machined from premium Swiss 7075 T6 aluminum and hardened to ensure maximum lifespan. The aluminum upper and lower nuts have a lower-profile design, including sealing O-ring and upper composite ball joint.
The well-proven pistons remain unchanged, and the set includes 3- and 4-hole pistons with 1.0, 1.1, and 1.2mm diameter holes. The pistons are molded using special processes and composites to ensure extreme roundness while maintaining maximum stiffness and durability.
All the parts of the ULP shocks are specifically designed for the lowest possible size to reduce the weight and keep the lowest possible CG.
Shock bodies are CNC-machined from premium Swiss 7075 T6 aluminum and hardened to ensure maximum lifespan. The aluminum upper and lower nuts have a lower-profile design, including sealing O-ring and upper composite ball joint.
The well-proven pistons remain unchanged, and the set includes 3- and 4-hole pistons with 1.0, 1.1, and 1.2mm diameter holes. The pistons are molded using special processes and composites to ensure extreme roundness while maintaining maximum stiffness and durability.
The XRAY servo saver has become the industry-standard saver and remains unchanged and is included in each X4F kit.
Several linkage mounting positions are offered to make the steering linkage adjustment easier. The servo saver consists of 4 springs which makes the servo saver strong enough to provide the precise steering racers demand, while still being flexible enough to prevent servo damage in hard crashes. The servo saver has interchangeable bushings to fit most popular servos.
The XRAY servo saver has become the industry-standard saver and remains unchanged and is included in each X4F kit.
Several linkage mounting positions are offered to make the steering linkage adjustment easier. The servo saver consists of 4 springs which makes the servo saver strong enough to provide the precise steering racers demand, while still being flexible enough to prevent servo damage in hard crashes. The servo saver has interchangeable bushings to fit most popular servos.
To ensure maximum performance, the X4F's high-precision pivot balls are machined in-house and then black coated or nickel coated for a smooth and long lasting finish. To maintain proper balance through every run, the in-house machined top deck screws ensure tweak free handling from start to finish.
The 1-belt 2WD drivetrain concept provides maximum efficiency featuring 3mm narrow drive belt that has been specially ground for minimal thickness and maximum flexibility.
A full set of 20 high-speed, blue-sealed and steel ball-bearings are used throughout the drivetrain, steering and anti-roll bars to ensure maximum efficiency.
A full set of 20 high-speed, blue-sealed and steel ball-bearings are used throughout the drivetrain, steering and anti-roll bars to ensure maximum efficiency. All of the bearings are degreased and oiled with Aero Shell® Fluid 12 for maximum smoothness and long life. The bearings used in steering blocks and uprights have been specially selected to reduce unsprung weight and maximize drivetrain efficiency.
Both front and rear bulkheads feature additional integrated belt-tension adjustment through the use of adjustable bearing eccentric holders. These holders are also reversible to move the differential height from the lower or upper position that is now +1mm higher than the T4 platform.
Both front and rear bulkheads feature additional integrated belt-tension adjustment through the use of adjustable bearing eccentric holders. These holders are also reversible to move the differential height from the lower or upper position that is now +1mm higher than the T4 platform.
The wobble-free anti-roll bar system is mounted to the front & rear bulkheads via bearings for extra-smooth movement and quick & easy changes and adjustment the X4F comes with specifically chosen thickness of anti-roll bars for best possible performance out of the box.
X4F features front 1.3mm and rear 1.2mm anti-roll bars.
The roll bar rotates in ball-bearings for maximum precision and free movement. Anti-roll bar height is adjustable via a screw.
The complete range of different anti-roll bar thicknesses is designed to work with the ball-bearing roll bar mounting system.
Anti-roll bars have laser-engraved stripes (corresponding to bar thickness) for easy identification.
The wobble-free anti-roll bar system is mounted to the front & rear bulkheads via bearings for extra-smooth movement and quick & easy changes and adjustment the X4F comes with specifically chosen thickness of anti-roll bars for best possible performance out of the box.
X4F features front 1.3mm and rear 1.2mm anti-roll bars.
The roll bar rotates in ball-bearings for maximum precision and free movement. Anti-roll bar height is adjustable via a screw.
The complete range of different anti-roll bar thicknesses is designed to work with the ball-bearing roll bar mounting system.
Anti-roll bars have laser-engraved stripes (corresponding to bar thickness) for easy identification.
HUDY Exclusive Silicone Oils are manufactured in Europe and each batch is laboratory tested and calibrated to ensure the highest possible consistency and quality from batch to batch. 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 will get for your car are exactly same as those used by the factory racing team, thus ensuring very exacting set-ups and handling.
HUDY Exclusive Silicone Oils are manufactured in Europe and each batch is laboratory tested and calibrated to ensure the highest possible consistency and quality from batch to batch. 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 will get for your car are exactly same as those used by the factory racing team, thus ensuring very exacting set-ups and handling.
The chassis features pre-drilled holes for additional weights for optimum car balancing and centerline holes for easy balancing with the HUDY Chassis Balancing Tool #107880.
The extensive and impressive range of adjustment possibilities includes: ARS (Active Rear Suspension™), caster, camber, toe, anti-dive, anti-squat, ride height, downstops, track-width, lower roll center, upper roll center, roll center positions, steering roll center, wheelbase, Ackermann, steering lock, bumpsteer, belt-tension adjustment, adjustable shocks, adjustable in-line flex adjustment, adjustable front chassis flex, diff height and adjustable diff.
The extensive and impressive range of adjustment possibilities includes: ARS (Active Rear Suspension™), caster, camber, toe, anti-dive, anti-squat, ride height, downstops, track-width, lower roll center, upper roll center, roll center positions, steering roll center, wheelbase, Ackermann, steering lock, bumpsteer, belt-tension adjustment, adjustable shocks, adjustable in-line flex adjustment, adjustable front chassis flex, diff height and adjustable diff.
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.
To get the finest tips & tricks on how to build the X4F or to learn more about each of the set-up options, follow the series of XRAY X4 Tech Tip videos featuring Alexander Hagberg and Stefan Schulz. The videos walk through each section of the building process with suggested assembly techniques, demonstrations, and detailed explanations of the various setup adjustments.
Please note that the videos are made specifically for the X4, but will contain very good information that may apply to the X4F as well.
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 Tech Talk groups. 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.
Owning an XRAY model racing car is an experience on its own. Get the VIP customer treatment.
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 Tech Talk groups. 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.
Designing the X4.
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Designing the X4.
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Making of the X4.
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Making of the X4.
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