Two months prior to the release of these rear A-arms for the HPI Baja 5B & 5T, we released our version of the front A-arms. In that short amount of time, the durability of our Baja A-arms displayed their unbeatable nature! That kind of performance can now be matched out back with our rear A-arms for the 5B & 5T.
RPM Baja rear A-arms start with the basic geometry of the stock arms so they are direct replacement parts – no additional parts will be needed. However, we’ve made a number of modifications to the arms from there to improve performance and durability.
In the performance department, we moved the rear hub carrier forward by 1/8” over stock geometry. While this does little to change the overall wheelbase of the vehicle, what it does do is alter the angle of the drive shaft as it exits the differential. This reduces the tendency of the Baja to squat under acceleration. This happens when the torque of the motor is opposed by the force of friction created by traction at the rear tires causing chassis squat, consequently causing a loss of grip. By sliding the rear hub carrier forward, we use the torque of the motor to effectively “push” the rear wheels into the ground, using both the weight of the Baja and the torque of the motor to improve acceleration performance. Up top, RPM rear upper A-arms have had a shape change for added lateral stability – the stock “Y” shape tends to allow the upper pivot ball to move forward and backward while the RPM “D” shape holds the upper pivot ball in place more solidly, providing a more consistent feel to the performance of the Baja.
This product was added to our catalog on March 24, 2009