Low speed electric vehicles (LSVs) are becoming wildly popular these days for a number of reasons. They’re quiet, fun, and relatively comfortable to drive, but more importantly, they don’t use fossil fuels. However, newer LSVs like the GEM and others can be very expensive and not a practical purchase for those who would only use them occasionally or on weekends. Welcome out of warranty “lease” golf course fleet vehicles (golf carts) to the rescue. Club Car, EZ-Go and other three-year-olds are featured in the thousands at auctions in the US each year. Some end up in neighborhood classifieds or used car lots after a quick cosmetic makeover. Many of them head to “chop shops” where their original golf paraphernalia is stripped, jacked up, outfitted with flashy tires, carbon fiber dashboards, plush upholstery and satellite radios. They have painting themes ranging from their favorite adult beverage to their alma mater gear and more. A $ 1,400 golf cart magically transforms into a $ 6,000 “pride ride” for some lucky consumer.
The only thing these vehicles typically have in common under the fabulous makeover are old batteries and components. The other thing is; they are usually set to operate at really slow speeds (about 12 mph). You who have rented golf carts at your local course know why you are doing it. To operate on public roads and be categorized as an LSV, many municipalities require the vehicle to go 20 mph and it must be equipped with lights, seat belts, and a horn. The lights and seat belts are easy enough to handle, but getting your car going 20 mph is another story. Even if you’re not trying to make it street legal, most users want the extra speed capability just to add more utility and enjoyment. 12 mph is too slow for most users. If you think 12 mph is fast enough, wait a few weeks.
Okay, so you’re ready to do whatever it takes to get that baby flying. Well maybe 20 mph isn’t exactly flying, but it sure will feel like it is if thrown at that speed. Seat belts are a good idea at any speed. The first thing to determine is how fast you really want to go and how you are going to use the vehicle. Is the terrain flat or rough? Will you carry cargo of any substantial weight (No, I don’t mean your mother-in-law)? For hills and / or heavy loads, you will also need to increase the carriage torque. This means a more powerful motor and probably an improved motor controller to handle the extra current demands of the motor. There are several vendors that can supply such updates, but they can be expensive. Make sure to do your homework and shop around. If you only have a standard cart and are using it on basically flat terrain, you have a few more options:
• Higher tires – Increasing the diameter of the drive wheels increases the distance they will roll for each revolution of the axle, thus increasing the speed at which your car will go. You first need to know how fast you can go on standard 18.5-inch tall tires. Most portable GPS units can be used as a speedometer to find that. If you don’t want to do math, there are several free online calculators to help you determine how much speed you will get on the new taller tires. A very good one is on the Digital Overdrive Systems website. Although increasing the size of the tire will increase its speed, the torque will suffer a bit. That means you may have to leave your mother-in-law at home! The size of the tires is also limited by the opening of the wheel. Most large tires require the car to be “lifted”, which is not always desirable and can be expensive. The speed gain is relatively small (an increase of a couple of mph)
• High speed gear set – In the case of the differential or rear axle, resides a gear reduction system. The motor has a small gear that drives the largest gear on the shaft. Normally, the motor rotates about 12 times for each revolution of the shaft. This is how the relatively low-power motor gains a mechanical advantage to power the car. Like the gears on a bicycle, pedaling is easier when the drive sprocket is on the small diameter one. To go faster, you must advance to the largest drive sprocket. The bike goes faster, but it is more difficult to pedal. In a golf cart speed gear set, the ratio changes similarly as the diameter of the drive gear increases, and the cart runs faster. However, like the bicycle, the motor has to provide more “torque” force to the axle. This type of mod is great for speed, but will sacrifice low-speed torque (your mother-in-law again) and is not recommended for mountainous areas. Installation can be tricky due to gear lubricant and requires some skill and knowledge.
• Increase engine RPM – Increasing the revolutions per minute or RPM of the engine is one of the most popular techniques for increasing the speed of a golf cart. This type of mod doesn’t sacrifice low-end torque like the two mentioned above. Golf cart electric motors are designed to run at certain maximum RPM (typically around 3600 RPM) at 36 volts or 48 volts and provide a good balance between speed and torque of the end product. Aftermarket motors have their field and armature windings redesigned to achieve higher RPM than stock. If the engine turns at twice the original RPM, a 12 mph car could hit up to 24 mph. The motors are safe and reliable, but may require the addition of a high-current driver to operate at their full potential. Aftermarket “speed motors” are available from a number of vendors, but can be quite expensive due to all the copper wire in the windings. There is a vendor that provides a really simple and easy upgrade for Club Car IQ cars called SpeedyLink, which increases the RPM of the original engine by about 50% with no additional modifications.
Whichever method you use to increase the speed of your golf cart, be sure to use good judgment and use the proper safety equipment. The stroller can be fun and functional for everyone and has many applications. Rest assured enjoying your fast golf cart. Stay tuned for more articles on golf cart upgrades and maintenance.