MST RMX 2.5 Classic GR86RB Kit

The kind of vehicle the maker sells it as. It sets what the car is built to do and which cars it is fair to compare it with.

• Drift cars are set up to slide through corners on hard plastic tires, with the rear wheels turning faster than the front or driven alone.

Only the rear wheels are driven.

• Modern drift chassis are mostly rear-wheel drive and use a steering gyro to hold the car at an angle through a slide.

Sold without a motor, so you choose the motor, ESC and battery yourself.

• Rows that depend on the motor say so.

A kit you build yourself from parts.

• Most kits come without motor, ESC, servo, radio and battery, and many without tires or a painted body.
• The manual lists what to add.

The maker's nominal size compared with a full-size vehicle. It works more as a class label than a measurement.

• A 1/10 monster truck is far bigger than a 1/10 touring car, so compare length and weight for real size.

The maker's product number for this exact version.

• A V2, a new color, or a kit instead of an RTR usually has a different number, and parts can differ between them.
• Check it against your box or receipt before ordering parts.

The small gear on the motor shaft. Fewer teeth gear the car shorter: quicker acceleration, lower top speed and a cooler motor. More teeth do the opposite.

• It depends on the motor you fit, so the maker does not list one.

The large gear the pinion drives. A bigger spur with the same pinion gears the car shorter.

• Pinion and spur must have the same pitch, or tooth size, to mesh.

Every reduction after the spur, multiplied together: transmission, differentials and axle gears.

• It is fixed by the design; the gearing you change is the pinion and spur.
• On a belt-driven drift chassis it takes in the pulley ratios as well.

How many times the motor turns for one turn of the wheels. A higher number is shorter gearing: more acceleration and pulling power, less top speed.

• Drift cars are geared for fine throttle control through a slide more than for top speed.

The outside diameter of the mounted tire, tread to tread. A taller tire covers more ground each turn, which gears the car taller.

• Drift tires are hard plastic and barely change size as they wear, so the gearing stays put.

Motor KV is the RPM a motor turns per volt with no load.

• This vehicle comes without a motor, so there is no stock KV; it depends on the one you fit.

The highest LiPo cell count the maker rates the electronics for.

• This vehicle comes without electronics, so it depends on the ESC and motor you fit.

It needs a motor KV, and this vehicle comes without a motor. Fit one and the calculator works it out from the motor's KV and the gearing.

The distance between the front and rear axle centers. A longer wheelbase is steadier at speed and over bumps; a shorter one turns more tightly.