The Definitive Guide to Mini-Z / 1:28th scale Differentials: Mini-Z/1:28 比例差速器官方指导说明

The Definitive Guide to Mini-Z / 1:28th scale Differentials

The stock gear differential that comes with most Mini-Z offerings from Kyosho has a lot of friction and play making handling difficult and unpredictable.

Upgrading to an adjustable ball bearing differential, an adjustable metal gear differential or a clutch-type gear differential will provide a smoother throttle response  and a much more stable rear end compared to the stock gear differentials from  Kyosho. After tires, your differential is the second most important aspect of your car's handling so choosing the correct one needs some consideration.

All differentials have pros and cons; some are better suited to different classes or  tire choices

  • Make sure you choose the correct differential shaft length for your motor mount.

Traditionally there have been the "regular" length shafts compatible with HM (high  mount), RM (rear mount) and MM (mid-mount) motor pods (motor mounts) and then there was a longer shaft for LM (low motor) motor pods.

The double-bearing pro adjustable ball differential from MC3WLS is the best of both worlds. The differential fits a "regular" motor mount but is longer by 2mm on each  side. This means that instead of using +3 rims, which has lots of deflection due to their larger lips, you can use a +1 rim which has less deflection while still maintaining the same wide wheelbase.   

  • While upgrading your differential, you should also change your gear pitch to 64 or 126 from the stock 48.

It usually doesn’t cost you extra and will give you smoother throttle control and more power due to reduced friction. Although 126 pitch gears are very smooth, the pinion gears wear out extremely fast and can be destroyed easily if the meshing isn’t set correctly. So, it’s not just the pitch that matters, but also the material the gears are made out of.

The MC3WLS double-bearing pro adjustable ball differential features a set of  precision injection molded POM (aka Delrin or Acetal) spur gears and pinions. The included spur gears range from 52 to 54 teeth and pinions range from 9 to 12 teeth. This gives you many different options for gear ratios that can be a pivotal part of setup especially in stock classes. Delrin aka POM or Acetal is a slippery material and well known to be beneficial in applications such as  gearing where friction should be minimal compared to other materials like ABS or nylon which other manufacturers use for their gearing.

Look for differentials like MC3WLS's double-bearing pro adjustable ball differential kit  that come in a package with various sized pinions. This will give you more tuning options and save you money.


Here are some pros and cons of the different types of differentials on the market.   

Standard Ball Differentials (Kyosho, GL Racing, Atomic R/C, Nexx Racing,  3Racing)


  • Smoother operation than stock gear differentials from Kyosho
  • The amount of diff action aka slippage is adjustable
  • Works well with motors that have a lot of torque because it allows some slipping if you over-throttle out of a corner (although it is not recommended to set your diff that loose)

PN also makes a Limited Slip Ball Differential (LSD) gear which locks the diff at higher RPM. It works very well, has smooth operation and keeps the rear stable.


  • You might have some power loss at points on the track depending on how lose you set the diff, robbing you of motor power
  • Requires more cleaning and maintenance than other differentials as the diff  components are exposed to the external environment
  • These designs use radial bearings only which are only meant to handle centrifugal (e.g. spinning) forces only. They are not meant for lateral loads which exist when running the diff. Over time, the races wear on the outer axle radial bearing and performance suffers. Additionally, these designs can suffer inconsistency as the diff setting can tighten up just a bit through the run to change the handling characteristics of the car
  • This design uses an e-clip to secure the outer wheel hub onto the shaft. To rebuild the diff requires removing this frustrating clip along with having to loosen the tension adjustment nut which means losing your diff setting. The e-clip can also become bent when taking it on and off and this can cause inconsistent differential action as the e-clip can get caught on the radial bearing.

Metal Gear Differential (PN Racing)


  • Does an excellent job of transferring power to the ground all the time
  • It can be set very loose and at the same time will not rob you of motor power. For this reason, it works best with stock class motors where corner entry speed and motor torque are lower


  • Difficult to drive if you have a high KV motor
  • Can become easily damaged if you’re not careful with the threaded adjustment collar as it can come loose while running. 

Clutch-type Limited Slip Gear Differential (Atomic R/C)

Atomic R/C issued this design a while back for the Kyosho MR-03 but then included it  as part of their MRZ RWD chassis. This differential is a type of limited slip gear  differential. It uses a centrifugal clutch that locks the rear differential at a specific  RPM. When you are off-power, the clutch disengages and this allows tighter cornering  as the differential can work. When you are on-power, the clutch re-engages locking  the differential and causes the car to understeer or push out of a turn.

Unlike the PN LSD ball differential, you can purchase different clutch O-Rings that  engage the clutch earlier or later, allowing you to fine tune the differential to the track  conditions. If you have too much initial turn into the corner or are oversteering out of  the corners, then you can use a softer O-Ring to keep the diff locked at lower RPMs. You can also use a harder O-Ring to get the reverse effects.


  • Works best with cars that are setup with a bit of oversteer
  • Spur gear is quick and easy to change; it takes less than a minute
  • Makes the rear of the car more stable and allows you to take the corners tighter when compared to a regular ball diff or the stock Kyosho gear differential
  • Differential gears are fully enclosed in an outer casing so you never have to worry about dirt getting into them
  • Clutch system works well and provides a very smooth feel, both on and off-power.


  • Design miss in that there is some play between the side gears (attached to the shaft) and spider gears (4 small gears) causing there to be some excessive friction when turning as the lateral forces cause the side gears to push into the spider gears. This makes the differential action inconsistent even when taking the corner with the same line and speed as the previous lap.
  • Requires additional parts to make the diff work consistently:
  • You need to put a 0.4mm washer on both sides of the spider gear assembly to ensure they stay the correct distance from the side gears.
  • Use a custom cut brass bushing (cut from brass tubing) inside the centre of the spider gear plastic housing to add some strength and reduce friction

MC3WLS Dual-bearing Pro Adjustable Ball Differential

This design features two types of ball bearings: a thrust bearing controls axial loads  while the outer diff half bearings controls centrifugal loads. Using a thrust bearing in place of a radial bearing allows you to fine tune the amount of pressure between the plates as the outer hub rotates freely on the thrust bearing. This combination allows more precise transfer of power which means more throttle control providing a more consistent handling car lap after lap.


  • A proper thrust bearing just like 1/12th scale cars: Throughout a race, the diff maintains a very consistent feel since the axial loads from the pressure plates are managed by the thrust bearing. The thrust bearing allows for more precise differential action giving you better and more consistent grip through a corner when compared to a standard ball differential. It also allows for finer adjustments and prevents “locking” of the differential when the diff is set tighter.
  • No more eclip: a threaded shaft and a specially designed nut replaces the e-clip allowing rebuilding of the diff without losing the diff setting (e.g. it is not required to loosen the tension adjustment nut in order to take apart the diff for maintenance)
  • The diff right wheel nut also assists in not overtightening the actual (outside) wheel nut that holds the wheel unto the diff hub. Most racers traditionally overtighten this nut creating binding
  • The kit comes with 12 ceramic balls as stock
  • The kit comes with titanium coated differential rings stock; these d-cut rings can also be used to replace PN Racing rings
  • The kit comes with a set of spurs and pinions
  • The kit is compatible with the yellow PN spur gear that must be used in the GTLM Super Stock Class.


  • Not compatible with narrow width chassis
  • Not compatible with LM motor pods
  • You likely cannot reuse wheels that were previously built for other diffs as the diff is 2mm wider on each side when compared to a standard Mini-Z differential. This means using a +1mm wide offset rim is equal to a +3mm offset wide rim on a standard Mini-Z differential

MiniZ1:28 比例差速器官方指导说明




  • 确认你选择的差速轴的长度适合马达座


MC3WLS出品的双轴承可调珠差是最好的选择! 这款珠差适合标准马达座,比普通差速轴每侧长2mm,这就是说可以代替了3度轮毂(过大的轮毂offset凸起会导致偏心),如此,在相同宽度的轮距下我们用1度轮毂就会比3度轮毂减少偏心影响

  • 当升级差速器的时候,也相应应该将48p齿轮升级到64P或126P





标准珠差(KyoshoGL Racing Atomic R/C Nexx Racing3Racing


  • 比京商标准齿差更平顺运行
  • 珠差的 AKA 侧移量(松紧)可调
  • 当你在弯角处油门过大产生侧滑时与马达更好的配合提供更多扭矩(虽然调松差速是不建议的选择)

PN 也生产了一款在高转速下的限滑差速器,运行起来平顺,车尾稳定


  • 在某些设定下,你会损失一些动力
  • 比起其它部件外露的差速器需要多一些清理和维护
  • 此款设计使用了向心轴承只能负担离心力(如旋转力),而不适合差速器运转时横向载荷。随着时间的推移,外轴径向轴承上的座圈磨损,性能下降。此外,这些设计可能会出现不一致性,因为在整个运行过程中,差异设置可能会稍微收紧,以改变汽车的操纵特性

  • 此设计使用E形卡环将外轮毂固定到轴上。要重装差速,需要移除这个比较麻烦的卡环,同时必须松开张力调整螺母,这意味着失去原有的差速设置。当拆卸E型卡环时,卡环也会弯曲,这会导致差速器动作不一致,因为E形卡环可能卡在轴承上。

金属齿差速器(PN Racing



  • 持久提供良好的动力传输
  • 即使差速调的很松,也不会损失动力,因此这种差速适合在弯处不需要更多动力的 stock 组别的马达


  • 当使用高KV马达时很难操控
  • 若使用调节螺母时候使用不当,会造成在行驶中松掉进而损坏差速器

限滑差速器(Atomic R/C

Atomic R/C 应用这种设计可以追溯到MR03车架中,而现在也用在MRZ 车架中。


与PN LSD差速器不同的是,你可以选购不同的离合器O圈,来调节离合器工作时间提前还是延迟,使得你可以根据赛道条件调整差速器到最佳节奏。如果你在入弯时候转向过度,你可以用比较软的O圈来保持差速器在低转速下是锁住的。当然你也可以使用硬一些的O圈来获得相反的效果


  • 更适合容易专项过度的车架
  • 大齿很容易更换,通常不需要一分钟就可以弄好
  • 使得车子尾部更稳定,也会让你比使用普通京商齿差更加贴近弯角
  • 齿轮都封闭在一个外壳中,不用担心赃物进入到差速器里面
  • 离合系统工作非常好,在给油和松油时也都提供了平顺的感觉


  • 设计不足,即侧齿轮(连接到轴上)和十字轴齿轮(4个小齿轮)之间存在一定间隙,导致在转动时产生过大摩擦,因为侧向力导致侧齿轮推入十字轴齿轮。这使得即使在以与前一圈相同的路线和速度转弯时,差动动作也不一致。
  • 需要额外的部件才能让差速器持续工作
    • 您需要在十字轴齿轮组件的两侧放置一个4mm垫圈,以确保它们与侧齿轮保持正确的距离
    • 在星形齿轮塑料外壳的中心使用定制切割黄铜衬套(从黄铜管切割),以增加强度和减少摩擦




  • 一个合适的推力轴承就像1/12比例的汽车:在整个比赛中,差速器保持一个非常一致的感觉,因为来自压力板的轴向负载由推力轴承管理。与标准球差速器相比,推力轴承允许更精确的差速器动作,使您在拐角处获得更好、更一致的抓地力。当差速器设置得更紧时,它还允许进行更精细的调整,并防止差速器“锁定”。
  • E型卡环:带螺纹差速轴和特殊设计的螺母取代了E型卡环,允许在不丢失设置的情况下重建差速(例如,拆卸维护时,无需松开张力调整螺母)
  • 差速器右轮螺母也有助于不过度拧紧将车轮固定到差速器轮毂上的实际(外侧)车轮螺母。大多数赛车手经常过紧这个螺母,造成束缚
  • 套件自带12颗陶瓷珠
  • 套件配备镀钛涂层的珠差盘,可以用于PN差速器
  • 套件配有一整套大齿和马达齿
  • 套件与PN黄色大齿相配使用时需在GTLM Super Stock组别使用


  • 与窄体车架不兼容
  • 不适用于 LM 马达座
  • 因为差速轴比标准差速轴单边宽2mm,所以之前车架所用的轮毂就需要进行调整更换了。例如现在用1度的轮毂就相当于用Miniz普通差速时所用的3度轮毂

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