Basics of Mini 4WD | ||||
Part of the chassis | ||||
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Basics of Grade-up Parts | ||||
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Intermediate and expert customizations | ||||
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Race categories | ||||
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The Chassis (Japanese: シャーシ, Shāshi) is one of the main components of a Mini 4WD car.
How it works
The chassis acts as the main frame for the Mini 4WD car. There's the bumper on the front, side-guards on the center-sides and rear stay on the rear for roller and mass damper setups. Inside the chassis, it contains several important components, including motor, gearing, batteries, bearings, driveshafts and battery terminals. Internal layouts and component placements are usually varied depends on the chassis.
On most Mini 4WD chassis, the motor was usually placed onto the mid-rear section, thus giving the rear-motored Mini 4WD car the 42/58 front-to-rear center-of-weight. There are exceptions, however, as some chassis has the motor placed onto the front (i.e. FM-A Chassis) or onto the middle (i.e. MA Chassis). On some chassis, motor and/or battery compartment can be accessed from under the chassis by removing the underpanel(s).
Over the course of Mini 4WD racing history, designs of the chassis has gradually evolves. Newer chassis has matured chassis structure, lower center-of-gravity, widened bumper and rear stay, and has the POM-made plastic bearings equipped.
On the MS Chassis, the only module-like chassis even existed, has the separate nose, center, and tail units that can be swapped individually, allowing better maintenance.
Power loss and breakage
On circuits with a lot of ups and downs, the chassis may being temporaily bends and/or twists during those non-flat-surface sections. Temporaily bended and/or twisted chassis may causes power losses as moving part of the internal drivetrain components are touching the chassis's drivetrain chambers as well as the gears being pushed. This is more apparent with chassis that has weak chassis structure or has its weight shaved by removing part of the chassis structure.
In additions to this, weak structure or weighted-shaved chassis may face another problem: Breakage. Since the chassis has to receives impacts from landing and has to being pushed upward (depends on the circuit), those chassis will eventually breaks.
The solutions to both problems is either the use of the more rigid chassis or the use of reinforced chassis, or both. Newer chassis like AR Chassis, MA Chassis and FM-A Chassis has more rigid chassis structures compare to the prior chassis. Reinforced chassis were usually sold as limited GUPs, but some general Mini 4WD kits may includes them as well.