KMD-FR02 INSTRUCTION MANUAL
TOOLS NEEDED FOR YOUR BUILD
• Needle Nose Pliers
• Xacto/ Hobby knife
• 4.5 mm Nut driver
• 0.5mm allen key
#2 Philips screw driver or 1.5 mm hex driver
• Soldering Iron
• Metal File
• 2mm tap
• 2mm drill bit
• Dremel/ rotary tool
• Wire Cutters
What you need to know before you begin building: The KMD-FR02 is a great chassis that when built properly is very fast and fun to drive. The first time you build the chassis it will take you approximately 3 hours to complete. The 3D printed material we use has very low tolerances, however there will be some filing, sanding, and drilling that you may need to do in order for the chassis to work at its best. Please take your time while building the chassis to ensure all parts are working correctly. Any binding spots, friction or play in the suspension and drivetrain can upset the balance of the car significantly. We hope you enjoy the FR02. Some of the parts shown in the pictures may be different from the ones found in your kit.
WARNING: The 3D printed plastic becomes very brittle when cold, always run the car when it is at room temperature.
Screw the two 3mm ball joint heads into the steering pod. Then screw in the 2.5mm ball joint head into the hole furthest away from the center of the pod. I found that using a 0.5mm allen key to open the whole makes it easier to get the thread on the 2.5mm ball joint head to bite into the plastic.
Insert the two 3x2x6mm ball bearings one on top and one on the bottom of the steering pod.
You will now need to build the steering linkages. The turnbuckles have markings on them, the side that has the larger “ring” is clockwise to tighten and the opposite side is counterclockwise to tighten. Screw in two 3mm ball joint sockets into the turnbuckle. The total length of the steering linkage should be about 23.60mm.
Attach the steering linkages to the steering pod by pressing the 3mm socket into the 3mm head.
Using three 2x4mm tapping counter sunk screws attach the steering post to the bottom carbon fiber plate. Place a 3x6x0.3mm washer onto the steering post then insert the steering pod into the steering post.
FRONT END ASSEMBLY
Using a 2mm drill bit open up the wholes in upper arms, lower arms and lower mounting brackets. I find that simply moving the drill bit in and out is better than rotating the drill bit. This will open up the whole and smooth out the plastic to create less friction.
You should also test fit the 3mm ball ends into the sockets of the suspension arms. If there is a lot of friction you will need to smoothen out the inside of the socket. I have found that you can add oil to the inside of the socket and then place a 3mm ball end head into a dremel tool. Then insert the ball end into the socket and spin it with the dremel. Do not spin for too long or too fast as the ball end will become very hot and will then melt the plastic ruining your suspension arm. Do not push the arm into the ball when the dremel tool is on, simply let it spin with very little pressure.
Another option which is more work but safer to do is to simple use 1000 grid sand paper and smooth out the inside of the socket. Be careful not to remove too much material otherwise the ball end will pop out of the arm during racing.
Insert the lower hinge pin through the lower suspension arm and lower mounting bracket. You may want to add some oil in order to reduce friction. Check to make sure the lower suspension arm can move easily up and down. If there is any friction you will need to open the whole more on the suspension arm or mounting bracket. It is also possible that there is friction between the arm and mounting bracket. In this case file the inside of the suspension arms so that there is a small amount of play between the suspension arm and the lower suspension mount. If there is too much play use a washer between the arm and bracket to reduce it.
Make sure that the spring pin can easily slide through the spring holder. If there is friction you will need to use a 2mm drill bit to open up the whole in the spring holder.
After testing the fit, place a spring and spring holder between upper tower and lower suspension arms. Then secure the assembly using a spring pin. You should screw the spring pin in to the point where the lower arms are on a slight downward angle (1-2mm below the mounting bracket).
Lock the spring pin in place with a 2x3mm set screw, screwed in from the top down.
SET UP TIP: Using more front droop will help with on power oversteer. Try not to screw in the spring pin too much (lower the front end), however be sure there is enough thread in the suspension tower so that the spring pin does not strip the thread. Add or remove preload spacers under the spring (you can also use different spring holders) to tune your front ride height instead of turning the spring pin in and out.
Insert the camber/caster adjustment sleeve into the top suspension bracket from the back with the flat screw driver slot showing to the back of the chassis. You may need to open up the top suspension bracket using a drill bit to get the sleeve to fit. The sleeve should fit tightly into the bracket, I found that pushing down on a table is the easiest way to push the sleeve in, just make sure everything is aligned.
By rotating the sleeve inside its holder you can adjust the camber of the front suspension arms. You will need to remove the upper arms to do so. You can also slide the sleeve forward and backward to adjust the caster. You do not need to remove the sleeves to do this, just loosen the top set screw and then tighten when it is in the desired position.
SETUP TIP: I recommend starting with the camber/caster sleeves in the position shown in the picture above. It is also good idea to move the caster sleeve as far forward as possible.
Attach the upper suspension arm by applying oil to the upper hinge pin and inserting it through the upper suspension mounting holes and the camber/caster adjustment sleeve. If there is any play between the suspension mounting holes and sleeve place a washer in between the rear suspension mounting hole and sleeve in order to remove it. Check to make sure the upper suspension arm can move up and down freely.
It is now time to make the steering knuckles. Screw in two 3mm ball joint heads into the top and bottom of the knuckle.
It is a good idea to add some thread lock to make sure they do not come free while racing (do this after you have finished building and testing that the front suspension works properly). Screw in a third 3mm ball joint head into the steering arm from the top down. Screw in the knuckle shafts into the front of the knuckle, once again it is a good idea to add thread lock to make sure it stays in place.
You can now insert the steering knuckle into the upper and lower suspension arms. Check to make sure that the suspension can still move up and down freely. Make sure the knuckles can rotate left and right with ease. If they are stiff the servo will not center properly. You will need to smooth out the sockets in the upper or lower suspension arms until there are no more sticky points.
Secure the frontend assembly to the bottom chassis plate using four 2x6mm tapping countersunk screws and the front wing. The frontend assembly goes on top of the bottom chassis plate and the front wing goes on top of the frontend assembly. Make sure that the frontend assembly and front wing are sitting flush to each other.
Secure the steering linkages to the knuckle arms by pressing the ball end socket on the steering linkage into the ball end head on the knuckle.
REAR END ASSEMBLY
Before securing the battery holder to the lower chassis plate make sure it can fit flush. You may need to remove a small amount of material in the area’s shown in the figure below using an Xacto knife. This will ensure that the battery holder sits flush with the chassis. Secure the battery holder to the lower chassis plate using five 2x4mm tapping countersunk screws.
Repeat the same process above for the rear chassis part. Make sure it sits flush with the chassis before securing it using three 2x4mm tapping countersunk screws. At this time you will want to make sure that the 3.5mm ball joint head fits smoothly into the rear chassis part socket. If there is friction you will once again need to smoothen out the inside of the socket. You can do this with sand paper or using the oil and Drimel tool process described in the front chassis assembly instructions.
Remove the side shock spacers from the rear motor mount using wire cutters. Place these to the side as you will need them later. Screw the 3.5mm ball head end into the motor mount. After you have assembled the entire rear suspension and checked to make sure it functions correctly you may want to add some thread lock to the 3.5mm ball joint head, this way it will not come loose while racing.
Separate the rear side arms using wire cutters, make sure the tabs are completely removed otherwise the side arms will make contact with the bottom plate.
Secure the rear side suspension arms to the motor mount using a 2x8mm tapping countersunk screw.
Make sure that both arms are equal in height to one another. The arms should be flat with the bottom of the motor mount. Make sure that they are properly secure otherwise they may rotate during racing and this will affect left to right balance in the car.
Insert the 3.5mm ball joint head into the rear chassis part socket. Now secure the rear side arms into the battery holder using a 2x8mm tapping countersunk screw. You should tighten the screw all they way and then loosen it a little bit so that the side arm can rotate freely.
The side arms should have some tension on them to keep the rear motor mount from wiggling side to side. If they are too loose you will need to add a small washer to the 3.5mm ball joint end to move the motor mount further away from the chassis in order to tighten the side arms. If the side arms are too tight you may need to file off some of the motor mount where the 3.5mm ball joint head is secured too. This will bring the motor mount closer to the chassis and reduce the tension on the side arms.
Check to make sure the rear motor mount can move freely up and down as well as side to side. If there are any sticky points you will need to remove the 3.5mm ball joint head and continue to smooth out the inside of the 3.5mm socket. It is very important to get the rear suspension to be smooth in order for the car to handle well so take your time.
Mount the engine to the motor mount using the provided motor mount screws and washers. Make sure that the engine wires are facing directly upward so that you will be able to attach the sensor wire.
Secure the side shock (with adjustment collar) onto the rear carbon fiber mount using a 2x10mm machine screw. Check to make sure you have the carbon fiber piece the correct way around and that the screw is put in from the bottom.
Place the side shock spacer (cut off from the motor mount) between the carbon fiber plate and side shock. Use a wheel nut to hold the side shock in place.
Using two 2x6mm tapping button screws secure the side arms onto the motor mount.
It is now time to solder the engine to the SwavE ESC. If you do not have a vice to hold the esc you can secure it to the table (or the box it comes in) using double sided tape. This will make it easier to solder. Make sure you connect the engine wires in the correct order, they are marked ABC on the engine and ESC. Solder the power cable to the esc making sure you connect the positive and negative terminals correctly.
Connect the sensor wire and receiver cable to the ESC. Then secure the ESC to the chassis using double sided tape. It’s better to secure the ESC on the opposite side of the chassis compared to the one in the picture below. This way the wires are not being impeded by the body post.
You will now need to connect your receiver to the ESC and GL servo. Make sure the ESC and servo wires are the correct way around for your receiver. If they are not you will need to change them around by pulling up on the “piano key” plastic tabs with an Xacto knife and pulling gently on the wire to release it.
Once everything is connect it is time to turn on the electronics. You will need to calibrate your transmitter to the ESC. Make sure all of your transmitter settings are in their neutral position before doing this. To calibrate the ESC hold the throttle in full reverse on your transmitter and then turn on the ESC. When you hear one beep pull the trigger to full throttle. When you hear two beeps return the throttle to neutral. Leave it in neutral until you hear three beeps, it should now be calibrated.
Make sure all of your steering settings are set to neutral on your transmitter. With the ESC on and the servo working make sure the servo is in the center position. You can now place the servo saver horn onto the servo, make sure that the C clamp tab is pointing directly upward. It is important to get this as close as possible in order to ensure you get equal left and right steering.
Attach the C clamp to the servo horn, I found that by twisting a flat screw driver in the open slot makes it easier to get the C clamp to fit between the servo horn tab. Secure the rest of the servo saver assembly by using the provided screw and washer.
Now screw the 2.5mm ball joint head into the servo saver. Use the trim function on your transmitter to make sure the servo saver it pointing directly upward.
It is now time to build the linkage between the servo saver and steering pod. You will need to cut off about 1.0 mm of plastic from one of the 2.5mm ball end sockets. Use an Xacto knife and simply press down once you have it placed the correct distance.
Secure both 2.5mm ball end sockets to each other using the provided set screw. From end to end the linkage should measure about 13.45mm.
Attach the linkage to the servo saver. Secure the servo saver to the servo mount using two 2x4mm tapping button screws. I have found that it is a good idea to use double sided tape as an extra measure to secure the servo to the servo mount. You can use your tire tape for this
Now secure the servo mount and servo to the bottom chassis plate using four 2x4mm tapping countersunk screws. Attach the linkage to the steering pod. You can now check that the steering functions correctly.
When the servo saver is pointing directly upward the steering pod should be centered. If it is not you will need to lengthen the linkage to move the steering pod to the right or shorten it to move it left. This will provide you with equal steering deflection left and right.
You should now unplug the battery. The ESC will draw power from the battery even when it is turned off. This could drain your battery to the point it can no longer be charged. Always unplug the battery from the ESC when you are not using your car.
Secure the top center shock to the top chassis plate using the two provided screws.
Place a 0.3mm washer on top of the steering pod before attaching the top plate. Make sure the engine wires are placed in a way that they will not affect suspension movement. Figure shows a general guide line of how to place the wires but you may choose a different way if you wish. Secure the top chassis plate to the chassis using five 2x4mm tapping button screws.
Secure the two side shock pistons onto the side shock mount using two 2x5mm machine screws.
Using the side shock springs and two 2x8mm tapping countersunk screws secure the side shock mount to the chassis. Make sure the side shock mount does not pinch the engine wires. Ensure that the engine wires do not impede the movement of the motor mount.
SETUP TIP: If you are using the stock side shock springs it is a good idea to reduce the amount of preload on the spring by loosening the adjustment collar. The amount of preload on the side shocks controls the left and right balance of the rear suspension. If you find your car is oversteering in one direction but understeering in the other direction then you will need to add more preload to the side that is understeering and/or remove preload from the side that is oversteering. You May whish to purchase the PN side shock spring kit in order to have more adjustment options. I recommend using the white or yellow springs when racing on RCP. You will need to increase the amount of preload for the optional springs as they are shorter in length compared to the stock spring.
Secure the top shock to the motor mount using a 2x5mm machine screw.
Insert the ball bearing adaptor into the motor mount then secure it in place using the 2x5mm set screw. Insert the 3x6x2.5mm ball bearing into the ball bearing adaptor. If the ball bearing is difficult to push into the adaptor use an xatoc knife to scrap away a small amount of material from the leading edge of the adaptor.
Place the pinion onto the engine. A gear ration of 5.3 is a good starting point. You can use a 53 tooth spur gear and a 10 tooth pinion gear. Now insert the differential into the motor mount and secure it using the set screw on the left diff hub. Check to make sure the gear mesh is correct between the pinion gear and spur gear.
SETUP TIP: If the differential is not properly functioning it will be very difficult to drive the FR02. Make sure the differential is very smooth with no grainy feeling or binding points. An imbalance in the differential will cause problems during on power corner exit. LSD type spur gears (such as those made by PN) do not work as well as a normal spur gear.
Secure the rear wing to the motor mount using two 2x5mm machine screws.
After tapping, gluing and truing the tires to the rims use the provided 3x6x2.5mm ball bearings and install them into your rims. Then secure the wheels to the chassis using the provided wheel nuts. Make sure you install the quick release nut on the left rear wheel (pro version).
You can place a battery inside the battery holder and secure it in place with the provided elastic. As a final touch you can balance the FR02 using two pens. Lift the car off the ground using the two anchor points. Add weight to the side of the car that is tipped upward until the car is level.
WARNING: The 3D printed material becomes brittle when cold. Always make sure the car is at room temperature before running.
WARNING: The ESC is sensitive to gear ratios. If the ESC is shutting off while the car is running on the track you will need to lower the pinion gear. Any gear ratio lower than 5.3 can result in the ESC shutting off. If you are experiencing shut offs check to make sure your gear spacing is correct or lower your pinion to increase the gear ratio. If you want to go faster you will need to get a higher KV engine.
Your car is now ready to run, check to make sure the car is tracking straight. Then test out the turning radius of both sides at slow speeds. If the turning radius is not equal on both sides you can use the travel % on your transmitter to make them equal. If your radio does not have that feature you will need to lengthen or shorten the servo steering linkage. Check for tweak in the rear of the car. If the car oversteers to one side and understeers to the other side at medium to high speeds than loosen the preload collar on the oversteering side to correct the tweak. You may also tighten the preload collar on the understeering side. If the car violently rolls at the beginning of a turn this usually means you have built something incorrectly. Either part of the suspension is binding during compression or has too much play. You will need to go over every suspension part to make sure this is not the case.
For more information on how to properly set up and tune your car you can purchase my book “MC3 Mini-Z Guide” on amazon.
Check out the minicarclubofcanada.ca website to get tips on how to paint your FR02 body. We also have sticker files you may download and use for free!!