This is the much anticipated revision to the ubiquitous Returner R3 line, in the Returner R4. This particular motor is the Hyperlite v4 from PiroFlipRC. Thanks to them for sending it over for testing.
Building on the excellent specifications provided for the ZMXv3 and becoming one of the most common motors in the miniquad racing scene, the Returner R3 and it's OEMs probably set the standard for the light weight, high performance 2206 motor.. Following on that success, the R4 and its OEMs has a lot to live up to. This version has some significant improvements to the old R3 design. The weakest link in the R3 was the bearings, and that has been addressed in the new design. The bearings have been upgraded to EZO bearings, which are reputed to be some of the highest quality bearings on the market. In addition, the shaft has been updated to 4mm internal 5mm external single piece shaft of a titanium alloy that according to BrotherHobby has been tested through multiple iterations to maximize strength without inducing brittleness, an often difficult balance to strike with titanium. As a byproduct, the bearings have increased in size from 3x8x4 to 4x9x4, which also has a significant impact on the bearing longevity and strength. The shaft is also secured in place with a screw rather than a circ-clip. Unfortunately, the screw seems to suffer from the same soft material as the DYS version, so the same care should be taken when removing it to avoid stripping it. Heating the screw with a soldering iron to loosen it, ensuring the correct size driver, and applying firm even pressure will be critical. If you can find a 12.9 steel screw of the same dimensions, an upgrade might be worth it if you are planning on repeated maintenance. The good news is that with the upgraded bearings and shaft, the likelihood of needing regular maintenance is fairly low. All those upgrades and the motor still ways just at 28g, which is quite impressive. Whether the changes meant to address durability will prove to be successfull will take flight testing and crashing, but overall this motor is very decent successor to the R3.
Given that this motor shares much of the internal design with the Tornado T2, there really weren't any huge surprises here. The motor performed basically on par with the T2, just a tiny bit short. Given the motor's lighter weight, the performance difference is insignificant. This motor also showed some slight efficiency gains over the T2, though very minor. Overall the R4 and its OEMs are a significant improvement on the R3, making this motor a worth upgrade. It will be interesting to watch the various OEMs and their diverse KV ratings hit the market and see how they place as well.