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So your kid wants to go faster but you have no clue where to begin? A few minutes spent reading this article will save you hours of headaches and possibly hundreds of dollars. Remember that the first rule of motorsports is that the more you spend the faster you go. It's no different with little cars. Quality motors, batteries, and gears cost money to develop and produce. A proper setup should last until your child outgrows the car. And your next child too.

Pick the right car: Just like with real cars, it's important to start with a vehicle that can take modifications well. The ride-on market is flooded with cheap chassis that have gearboxes and electronics which can't take any more power without major headaches. There's also cars that are too small to add speed with your kid's safety in mind. We find the best cars for modifying are the Powerwheels 12 volt vehicles (except Smartdrive) and Kid Trax 12 volt vehicles.
Inspect your car to make sure it's in good enough condition for modifying. What was a minor problem in a stock vehicle can become a major problem when you add more power. Things to check include:
- Is the rear axle bent? You have to roll it on a flat surface to see the bend. If it's bent you will melt gearbox housings at higher rpm's.
- Is the frame damaged or showing white stress marks around the rear axle mounts or gearbox seating area? This is critical damage that is not fixable.
- Do the tires have life left? Tires with holes will break gears.
- Is the wiring strong? Wires that are dried out will likely have corrosion on the inside. They may not handle the increased amp draw that comes with speed and you'll blow fuses.
- Are the switches strong? There's no way to visually inspect this. We recommend replacing them if the vehicle is 3+ years old. They're cheap.

One of the most common errors in modifying is mismatching the batteries, motors and gears. Matching them is as important to a ride-on as having a motor, transmission, and rear-end that all work together in a real car:

Motor: Stock 550 motors (which come in most vehicles) are only designed for 12 volts. Some people do run them at 18 volts but eventually they fail. At 24v the motors usually will not last a day. Our motors are the only motors specifically marketed as upgraded motors for ride-ons. Using a motor from a radio controlled car that weighs 5lbs is a recipe for failure. Our Performance 550 motors are designed to run at 12v or 18v. They come on all Stage I and II kits. Our Performance 775 Motors will run at 12v, 18v, or 24v. At 12v they are slower than the 550's. At 18v they are about the same speed as the 550s but with a ton more low-end power. 24v is where the 775s are at their best and are unstoppable beasts.

Batteries: Upgrading batteries give more speed gain than motors but again you have to match the right battery to the right motor to have the car last. Ride-on cars use SLA style batteries which use a gel form of acid. Using a lawnmower/motorcycle battery is dangerous as the liquid acid can boil and explode. They also overheat motors because of the different chemistry in the battery. Same problem with lithium batteries. Stick with SLAs. The amperage of the battery determines run time. Most vehicles have a 9.5amp battery stock. Our upgraded batteries are all 12amp. This means about 30% more run time. Stock batteries usually have 30amp breaker in them which often fails when using upgraded motors or increasing the voltage. Our batteries use 40amp replaceable fuses. If you switch to an 18v or 24v battery you will also need an 18v or 24v charger. Our battery conversion kits include the appropriate charger.

Gears: Upgrading gears is the least glorious but most important part of making a modified ride-on reliable. Most Power Wheels brand ride-ons produced in the last 10 years use a "7R" gearcase. Older models had "#7" gearcases which are discontinued. Fortunately 7R gearcases are a direct fit in those vehicles. The 7R gearcases are much stronger than the old 7s. Power Wheels continues to do upgrades to the molds of the 7R gearboxes so getting a new 7R is usually beneficial as well. Inside a gearbox are 5 gears. The Pinion Gear is attached to the motor. The First Gear is the gear contacted by the pinion gear and is the weakest in the gearbox. Then there is the Second Gear, Third Gear, and Final Drive Gear. The Final Drive Gear is what the wheel or driver hub attaches to. There are 4 different 7R gearboxes made today. Each can accommodate a range of gear ratios determined by the size of the pinion gear. The bigger the pinion gear the faster the car goes but at the expense of low-end power. Go too big and you will overheat the motor and blow fuses. If you are mud-bogging, hill-climbing, towing, or demolition derbying you will want a small pinion gear. If you are on pavement trying to do the Kessel Run in less than 12 Parsecs then bigger is better. Other brands of vehicles have one mid-ranged pinion gear size in for their gearboxes that you can not change the tooth count in.

Tires: The tires that come on the car are the tires it was designed to run. Changing tire diameter changes the gear ratio and can burn out motors. Ride-ons don't have a clutch in their gearboxes. They use the spinning tire as a clutch. Adding more traction with rubber or spikes removes the clutch and almost always overheats motors and breaks gears. Picking the right vehicle for your kid includes matching the tires it comes with to the terrain it will be used in. Monster Traction tires on the F150 are really bumpy on pavement. Mustang tires will not get traction easily in dirt. Tires are not interchangeable between vehicles so before you spend your time and money modifying make sure you've got the right foundation. You can't get no action if you ain't got no traction!

Which setup is right for you? That depends on your budget and need for speed. The fastest setup is a 24v Conversion Kit with a Stage IV Motor/Gearbox Assembly. Our next preferred upgrade is an 18v Conversion Kit with a Stage II Motor/Gearbox Assembly. You can easily upgrade a Stage II to a Stage IV later on by getting our 775 motors and motor mounting kit. Another popular way to upgrade in steps is to get an 18v Conversion Kit and run the stock motors til they blow. You will not harm anything else on the vehicle and can upgrade the motors as your budget allows. Putting a Stage I upgrade onto your otherwise stock vehicle will give a noticeable boost in speed which will make your kid smile and beat the neighbor's kid in a race. With ALL of these options we recommend adding a Brake Reduction Module (unless you have steep hills) which makes stopping a bit softer. Checkout our "Staged Upgrades Explained" guide for more information.

Please feel free to contact us if you have any question about which upgrade is best for your specific needs/budget.