If you've recently grown tired of your vehicle's performance, or you're just looking to win the next drag race, then you should consider enhancing your Tamiya RC car's top speed. By making a few upgrades and adjustments, you'll increase your ability to burn some high-speed rubber.
Purchase a ball-bearings upgrade kit for your specific Tamiya Chassis. You can find them at many online hobby shops, or special order them directly from Tamiya. Make sure to familiarise yourself with the model number of your chassis to keep you from buying the wrong kit.
Use the wrench to remove the bolts from all four wheels. Slide off the wheels, then pry out the plastic spacers seated inside the wheel mount. There are a total of eight spacers, two per wheel. Pry off the one facing you, then push the other one out through the back side.
Apply bearing lubricant to the eight bearings, then press them each into position, replacing all eight spacers. Ensure that they are firmly seated in the wheel mount, then slide all four wheels back on and fasten the bolts back in place.
Remove the screws holding the transmission housing in place. Locate the pinion gear, which is attached to the end of the motor arm, and the adjacent and much larger spur gear.
Unscrew the two motor mounting screws until you can rotate the motor can (the metal housing of the motor itself). Unscrew the spur gear mounting, then remove it from the transmission.
Install a new spur gear with a larger number of teeth, which are the grooves running along the edge of it. To increase the speed of your Tamiya RC, you need to replace your old spur gear with a larger spur gear. For example, if you have a spur gear with 58 teeth, purchase one with 70 or more.
Pinch a sheet of paper between the pinion and spur gears, then tighten the two motor-mounting screws to fasten the motor. The paper ensures a functional gap between the teeth of the gear, which minimises friction and maximises performance. Once you've remounted the motor, spin the gears to remove the paper.
Remove your old battery pack from the chassis. Disconnect the positive (+) and negative (-) battery terminals from the ESC by heating the soldered joints, then detaching them once the solder softens.
Install a new battery pack with stronger cells. Battery power is measured in milliamp hours (mAh). In other words, a battery rated at 3400 mAH is twice as powerful as a pack rated at 1700 mAh.
Solder the batteries to the ESC. Heat the soldering iron, apply a small amount of solder, then press the wires leading from the ESC against their respective battery terminals. Red connects to the positive (+) terminal while black connects to the negative (-). Remove the iron, and hold the wire in place for a moment to allow the solder to cool.