RR Tune-up1.
Smooth operation feeling. EX-RR ST-2 release.
Superior durability and operation feeling led by new angle sensor.
We adopt new angle sensor which was particular about the durability and the feeling of operation for both steering and throttle.  Prevents deterioration of durability and operational feeling due to wear, which can be said to be the problem of contact sensors.  Along with smooth operation feeling by smoother sliding, we realize high durability that is approximately 100 times compared with the prior sensor.  Therefore, the best feeling of operation can be maintained for a long time.  In addition, the new sensor outputs a more linear signal to the Master Unit. You can control the ESC and servo with a detailed operation sense.  A realization of a sense of unity between people and cars.
Increased the number of ball bearings that support the steering shaft for higher accuracy!
The number of ball bearings supporting the steering shaft has been increased from one to two. The double-support type supports higher precision operation and reliability.
The soft spring which can be operated with a constant tension.
The normal spring included in the extension unit has been modified. The previous spring used was a progressive spring becoming stiffer as the wheel angle increased, but the new softer spring give a linear stiffness as the wheel angle increases. Since the spring tension can be adjusted, you can set the spring tension to your personal preference.
It is possible to operate in constant linear tension.
The steering neutral position displacement has been reduced
Soft spring 
Normal spring
RR Tune-up 2.
Direct throttle feeling has been improved.
The newly designed throttle unit has increased the direct feeling.
Renovating the form by lengthening the throttle trigger and operational angle. In order to not influence the operational angle, the distance to the finger from the angular sensor has created a more direct feeling while maintaining a compact and comfortable size. With the direct feeling of the throttle/brake reaction when moved, the increase of this linear feeling allows for a smoother and quicker reaction with input on the throttle and brake.
Spring Tension Adjustment.
Trigger spring tension = personal preference. The new trigger unit provides a spring tension adjustment with a screw. This allows for a stronger or softer spring tension according to personal preference.
The long life period of the angle sensor’s smoothness does not change.
The new angle sensor used has proven to give a precise signal and shown durability. Because the signal is very precise, delicate movements are very fluid. The durability of the new sensor has shown approximately an improvement of 100 times over the past sensor used. Small operation feeling of the fingertip translates into a smooth and linear output to an ESC and servo.
RR Tune-up3.
The evolved software Ver.2.12
Calculator has rollout calculation.
This new function has been added to the calculator in the EX-2. Put TYRE DIAMETER in the calculator, ROLLOUT( Car movement distant per one motor rotation ) is automatically calculated. This is useful for changing gearing in a DD car.
New Push Control Function for Direct drive car.
A motor that has a strong magnetic force will add a braking effect when the throttle is released and will make a car stall in the corner. Setting the amount of forward input to remain on the throttle as the trigger returns to neutral can be adjusted. This is effective for F1, WorldGT and 1/12 category of cars whose gear ratio is small.
English⇔Japanese language change is possible in the menu.
You can change language in the display from Japanese and English. Selecting the display language that you prefer to use.
Adding various performance functions such as down timer and more.
Additional Functions

#Individual response settings for the steering and throttle.( Feel setting menu)
#Display RF mode (FH-G/ FH-F /MzMHS G/MzMHS F)
#2 way setting point in the Steering Speed.
#3 way Setting point in the Throttle Speed.
#Full acceleration settings.
#Full ABS Settings.
#Balance L/R added in the Steering override.
#Add User timer.
#35 model memory.

*This photo is screen of Down Timer

※In Ver.2.12, it is same function as Ver.2.1. Some changes with bug fixed.

Function Summary

Model Select / Model Name / Model Copy / Model Reset / All Reset

Display / Battery / Calculator / Sound / VR Information / Config / Key Speed / Menu Speed / Language / Operation time / User timer

Steering Travel / Steering Balance / Steering Trim/Steering Sub Trim / Steering Trim rate / Steering Speed Turn(2way) / Steering Speed return (2way) / Steering Curve / Steering Punch / Steering Feel / Steering Response / Steering Auto Trim / Steering Auto Balance /Steering Reverse

Throttle travel F / Throttle travel B / Throttle Trim/Throttle Sub Trim / Throttle Trim rate / Throttle Speed Turn(3way) / Throttle Speed reTurn(3way) / Throttle Curve / Throttle Punch / Throttle Feel / Throttle Response / Push Control/ ACCEL / ABS / Auto Start / Idle Up / Neutral Brake / Throttle Override / Throttle Reverse

KEY Setting / 2WAY / 3WAY / 5WAY / ANALOG / Gyro / Twin Servo / 4WS/AMP Mixing /Throttle Mixing / Trim Set

Timer Start / Trigger Start / Lap history / Start Stop Key / Lap Key / Lap Navi / Alarm time / Pre Alarm / Alarm Mode / Timer Mode (Lap Timer/Down Timer)

RR Tune-up 4.
Higher quality stylish wrapping.
Master unit and Grip Panel have carbon fiber printing.
ome screws used are aluminum for weight reduction.
New designed Aluminum Wheel.

#Weight:536g (not included battery)
#Battery: RO3/AAA/UM4 battery x 4
#Current: 150mA
#Using time: 4 or 5 hours( with alkaline battery)
#Channels:4 channels #Frequency:2.4GHz(FHSS)
# Model memory: 40
#Compatible receivers: KR-413FH,KR-241FH,KR-211FH,KR-212FHG.
*If you use Li-fe, Li-po, you must use with our option unit (Battery stand Unit).

Transmitter:(same as each models)
Master Unit EX-RR ×1
LCD Xpansion Unit EX-104S ×1
Aluminum Steering Wheel3 x1
Drop extension Unit2 ×1
Expert Grip Unit2(ライトハンド) ×1
Normal stand Unit ×1
Receiver:KR-418FH ×1
Other:RX mode selector x1
Transmitter : same as each models
Receivers:KR-418FH ×2
Other:RX mode selector x1
Transmitter : same as each models
Receivers:KR-415FHD(short) ×1
Other:RX mode selector x1
Transmitter : same as each models
Receivers:KR-415FHD ×2
Other:RX mode selector x1

#Dimensions:30 x 23 x 12.8mm
#Operation Voltage:4.8 to 7.4V
#Dual Antenna FHSS. DDS compatible.
#Number of channels: 4( compatible with HCS and Normal)
#Shield Wire antenna
#Gold Plated header pins
#Compatible for HCS.


#Dimensions: 28 x 18.3x 18.5mm
#Weight: 7.5g
#Operating Voltage: 4.8 to 7.4V
#Number of channels: 4ch
#Black Shield Wire antenna
#Gold Plated header pins
#HCS compatible


Please see here about HCS.

*HCS is working in FHSS use which is realized in the combination of compatible receiver and the servo. HCS do not work when using with Mini-Z.


Q & A

Q: Can the EX-RR be used for all Mini-Z?

A: EX-RR can be used for Normal FHSS( with our compatible receivers ) and MHS compatible Mini-Z.
EX-RR can not be used with non-compatible MHS Mini-Z.

Q: Can the HCS be used for Mini-Z?

A: HCS does not work with Mini-Z.

Q: Grip unit seems similar to Grip unit of EX-1. What are differences with these grips?

A:  Carbon printing grip plates and silver aluminum screws are different. The important point is the Trigger unit which operates the throttle is a renewed design. Angle sensor is new and other parts were renewed. You will notice a good feeling compared to the previous unit.

Q: EX-RR can be use with other receivers?

A: If you use the EX-RR with the KR-415FHD, you can use HCS but you can also use it in the normal FHSS mode. The previous FHSS corresponding receivers can also be used. (KR-211FH、KR-212FHG、KR-241FH、KR_411FH, KR-413FH, KR-418FH )

Q: Can the KR-415FHD be used with EX-1 or EX-2 transmitters?

A: Yes they can be used. Also HCS is a function between the compatible receiver and servo, so you can use HCS when using a compatible receiver and servo.

Q: What is Dual RX ?

A: Previous receiver have one antenna and one receiver circuit. KR-415FHD achieves a highly precise receiving performance with the use of a dual circuit and an external and internal antenna.

Q:  Is KR-415FHS's response faster than KR-413FH?

A:  Basically it is same response. It may feel faster than the KR-413FH with a fast operation system and the highly precise receiving performance. Also, it is faster then the KR-413FH when being used with the HCS.

Q: Is range shorter when using the short antenna version?

A: A: The performance is the same. But if short version is used with a gas powered car, the effect on the receiver is bad due to obstructions to the height of the antenna being lower. 
So we recommend using the short antenna version for use with electric cars only.

Q:Is Rx mode selector  for the KR-415FHD KR-418FH ?

A: Yes it is for now, but as new HCS compatible receivers become available it can be used with them as well.。

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