RRP RMX Conversion Kit – RRP-01RMX
The Rubrix Mid-Drive Project (RMX) - Clash of Champions Edition
The highly anticipated RMX Conversion Kit has arrived and has been engineered for compatibility with the stock Yokomo MX4 and MR4BC models. This release marks the return of a legendary mid-drive conversion, now reimagined with modern performance upgrades to meet today’s competitive racing standards.
 
Developed under the Rubrix Mid-Drive Project (RMP), the RMX Kit pays tribute to the historic performance of DBR and Chris VanAir at the JConcepts Vintage Clash of Champions. This platform and configuration helped propel VanAir to the top of the podium. Behind the scenes, Brian Dunbar played a critical role in refining this setup and his legacy continues to inspire innovation. This kit is a testament to his enduring impact on the sport.
 
Key features include:
Compatibility with RRP v2 & v3 slippers for enhanced drivetrain efficiency and fine-tuned adjustability.
Support for vintage Yokomo layshafts, maintaining backward compatibility while accommodating modern electronics.
Full xGen modernized conversion to support modern era electronics. 
The chassis is precision-cut from 3mm thick carbon fiber, featuring strategically recessed sections that reduce overall weight while maintaining strength in critical load-bearing areas.
Includes RRP Steering Assembly for the RX4E RRP-055XG
Using both the combination of DPRC BCYOKWCS-SUG Ti steering posts and hardware,
Includes the DPRC Carbon Fiber Steering brace RRP-021XG
The RRP RX4E & RXD models share the same steering system.
 
The RMX Conversion Kit is more than just an upgrade it’s a celebration of racing heritage fused with the demands of modern performance. Whether you're restoring a classic or optimizing for competition, the RRP-01RMX bridges the gap between past and present bringing the MX4 & MR4BC into the modern era of RC racing.
 
KIT INCLUDES:
RMX Box Art (DBR / CVA Tribute)
Engraved and Serialized RRP-RMX Chassis (3mm Carbon)
RRP Spring Steel CVD Set Front & Rear (RRP-064XG)
RRP RMP Layshaft & Motor Mount Set (RRP-02RMP)
RRP RX4E v2 Slipper Assembly Fits RRP RMP (RRP-003XG)
RMX Top Deck (2.5mm Carbon)
Rubrix xGen Front Shock Tower (3.5mm Carbon)
Rubrix xGen Rear Shock Tower (3.5mm Carbon)
RRP RX4E RXD Wing Mount Assembly AE B7 (RRP-076XG)
Dust Cover (1mm Carbon)
Front Bulkhead Brace (3mm Carbon)
DBR Front Camber Brace (3mm Carbon)
RRP Floating Servo Mount (Black) For RX4 RXD RMX Series (RRP-009XGBL)
RRP Sway Bar Set (RRP-034YZ)
RRP Complete Steering Assembly (RRP-055XG)
Includes DPRC Servo Saver Delete Upgrade (BOYOKSSD-1)
RRP xGen RX4 Evo v2 Lipo Tray (RRP-035XG)
2 x RMX Belt Sets (Short & Long - 4pcs total)
RRP Long Drive Belt Set (RRP-008RMP)
RRP Short Drive Belt Set (RRP-009RMP)
2 x RRP RMX Belt Tensioners (Top Deck attached)
 
OPTIONAL UPGRADES
AE 13mm Big Bore Shocks: +$150
RRP RX4E v3 Slipper Assembly Kit (RRP-082XG): +$30
Wheel Hub Set Worlds Specs (RRP-002MX): +$35
Lunsford style Titanium Turnbuckle Set: +$55
 
Considerations:
This is not a complete car. The RRP RMX Conversion Kit consists of specialized components designed to convert the Yokomo MX4, MR4BC, and MR4BC Special into a mid-drive configuration.
Yokomo MX4 differentials are preferred for the conversion. Stock MR4BC differential outdrives are typically plastic and they bind with our RRP Spring Steel CVD Set at full shock compression.
The rear RRP RX4E differential can be used with the RMX by applying 2-3mm shimming on the left side outdrive:
RRP Rear Differential Outdrive Set RX4E (RRP-008XGR)
33T Performance Differential Wide Pulley (RRP-014XG)
M2 X 15mm Differential Ti Screw and Thrust Bearing Set (RRP-032YZ)
3/32 (2.381”) Differential Chrome Steel Bearing Balls G10 (RRP-003YZ)
 
Additional Requirements:
A stock Yokomo MX4 front bulkhead cap is required.
An MR4BC rear differential cover is also needed.
These components are necessary, as they provide the appropriate fastening areas for the RMX top deck.
 
Pre-order delivery dates are based on a variety factors, including production availability and stock levels however again, our commitment will be to extend as many of these kits as we can.
Kit preparations and shipments will be processed in the order they are received.
The majority of these orders will have an average wait time of 6-8 weeks.
We ship worldwide and have managed to get products to most areas within a 6-10 delivery window, however this is not guaranteed.
For special shipment requests and other inquiries please contact us through our website contact form.