Kyosho Mini-Z RWD MR-03 MR-03EVO Full Review (a very late review)

MR-03 is the staple RWD platform in the Mini-Z series, designed and marketed to be the entry level race chassis on RCP and carpet tracks. It's fun out of the box and if you want to mod it, there are a ton of upgrade paths. More on that later. In terms of architecture, MR-03 is a classic and clean pan car design. The rear motor pod houses the motor and rear axle, and the whole thing is suspended by a springy t-plate and a top shock unit. The beauty of such a pan car motor pod design is that the main drivetrain requires only the motor pinion gear and the spur gear on the rear axle. Compared to a double wishbone + CVD rear end design, a pan car rear end is more power efficient, easier to maintain, and generates more traction on RCP. The t-plate at the bottom provides the primary source of rebounding forces along the up/down and twist motion of the motor pod. A t-plate system is straightforward to understand, and tuning means swapping in t-plates of different stiffness and material. The top shock provides an additional way to control the up/down motion, and adding some shock grease there provides some dampening effect along that axis. For speeds that MR-03 is capable of, this rear suspension design performs well enough and holds its tune easily. On a high traction RCP track, installing a soft t-plate is a good idea. The front suspension is designed around kingpins with rigid bottom arms and pivot top arms supported by springs. With rather short arms and without double wishbones, front traction isn't ideal. From a mechanical design standpoint, Kyosho traded some performance potential for simplicity. That's an acceptable trade off for MR-03. Changing the little front springs under the front arms is an important tuning tool. The stock MR-03 rear axle is a gear differential. It gets the job done, but for more tunability, people often upgrade to a ball differential by Kyosho or other brands such as PN and Nexx. The stock gear pitch is 0.5 mod, but it's common for third-party brands to use finer 64p gears for more gear ratio options. So far I showed you the standard Ready-to-Run version of MR-03. Kyosho has also released a more powerful version, MR-03EVO. The primary difference between an MR-03EVO and MR-03 is the upgraded electronics system. It's capable of powering both a brushed and brushless motor, which is a significant power upgrade. The EVO board uses separate EVO receivers so more radio protocols are supported, such as Futaba, Sanwa, and KO Propo. Not only that, the servo response is faster and more powerful. It is also configurable via a cumbersome USB and Windows PC setup, but it's very useful. My MR-03EVO here has many upgrade parts installed, such as alloy motor pod, ball differential, and upgraded servo parts. Otherwise, the architecture is identical to the standard MR-03. Please note that Kyosho has recently released the new MR-04EVO2. This means MR-03EVO will phase out eventually. Kyosho hasn't released an RTR MR-04 yet, but MR-03 will meet the same fate. One of the most awesome features of the MR-03 is its modularity. These three chassis are all MR-03, but using different motor pods, they achieve three different wheelbase lengths. Using the RM (rear) mount, the RTR MR-03 can support 86, 90, or The middle MR-03EVO uses an MM2 (mid) mount, can support 94 or 98mm wheelbase. The last one, PNR2.5W, uses an MML mount which can do 98 or 102mm. In addition to wheelbase, which is the distance between the front and rear wheels, MR-03 also supports a narrow vs wide front end. Why is this flexibility important? It means MR-03 can be reconfigured to fit all the available Autoscale bodies out there! It also means many parts are interchangeable and combined. Even though MR-03 isn't the fastest 1:28 car, I really enjoy modding and trying a huge variety of upgrade options. All in all, MR-03 is fast enough, durable, upgradable, and well supported. I'd bet most people running 1:28 started with MR-03. Even with plenty of non-Kyosho 1:28 RWD chassis out there, an RTR MR-03 is still relevant. Many clubs race the box stock class. MR-03 also provides a user-friendly path towards more serious 1:28 track chassis mentioned earlier in the video. For example, my current go-to track car is this GL Racing GLR-GT. Yes, it's faster than MR-03. Chassis like this are what people race in many clubs. While the build isn't super difficult, it's not all that trivial to build and tune properly, not to mention the upfront cost. It will not do a good job of attracting newcomers to 1:28 racing. An RTR MR-03 comes ready to go except 8 AAA batteries. If all this sounds good to you, the only remaining question is whether to wait for the MR-04 RTR kits to show up. Kyosho hasn't announced that yet but it's a sure bet. I'm personally more interested in the RTR than the EVO2. This is Sammy and thanks for watching! Music: "Journey to the Stars", Savfk (   • Journey to the Stars by Savfk [CC-BY royal...  )