I went on a small EV field trip to Arnolds in Oaks, PA. Check www.ArnoldsGoKarts.com for more info. Arnolds is an entertainment center which offers Electric Go Kart Races.
The Adult Go Karts are $15 for a ten minute session. You are required to watch a brief safety video, put on safety goggles (bring your own, rent for a dollar, or buy for $3) and a helmet (free), and then you can race.
The track is inside a warehouse with fairly slick concrete floors and stacked tire fenders. The Go-Karts look fairly substantial. The use stock go kart slicks. The wheels are surrounded to prevent contact and the karts have fenders. They are powered by 6 -12 volt Hawker Genesis batteries and a series motor.
The Karts have an interesting feature, in that the power available can be controlled remotely by the staff. When you start your laps, your kart is set at slow. After a lap or two, they use the system to turn everyone's power up. If there is an accident, they shut off everyone's power for safety. If someone is driving recklessly (well, the outer limits of recklessly), they can turn just that person's kart to low power. I find it often difficult to judge the relative power levels of vehicles. A high powered Kart with grippy tires can feel underpowered, while a lawn mower engine on rock hard tires feels like V8. I would guess that these Karts at the standard race settings were more powerful than the basic Briggs and Stratton Karts and less powerful than a Yamaha 100 Kart.
More importantly, the karts power to grip ratio was well balanced for fun driving. The Karts felt very responsive and not slow or heavy. They slide under cornering. Too much throttle can spin the tires, too much brake will lock them. At top speed, you would not want to hit the tire walls.
Transponders catch lap times which appear on a large TV screen in front of the stands. The current session times appear as they happen on the left side of the screen, fastest qualifier on top (think F1 Qualifying), while each persons best lap from the session before remain on the right side of the screen.
For the dedicated, they offer Pro nights. After racing at Arnolds ten times and being approved by their staff, they allow you to run races with the power set even higher.
The concept seems to be well thought out. The Karts are lined up in the pits in 6 rows of ten. The first group of up to ten Karts runs for ten minutes. As these Karts pull into the back of their row and start plugging in, the next group is leaving the pits to the track. The motors are unplugged and each kart is connected to a charger. The chargers were showing 60 amps when first plugged in, and have bulk, finish, float, and hot battery lights. According to a staff person, the Karts charge in less than 60 minutes and have a maximum run time of about 15 minutes. This allows maximum use of the track and by having six groups, allows the Karts to recharge.
Most Rental Go Kart tracks flounder because of poor maintenance. Less and less Karts can run, and the ones that do are so unequal in performance that they are not fun to race. The difficulties of maintaining ICE Karts is usually compounded by asking untrained minimum wage staff to fix the Karts.
With electric karts, the motor and controller should be minimum maintenance and hands off. The chargers looked automatic. Plugging in the Karts each session requires no training or special skills. One employee needs to be computer literate to run the software that posts times and controls power. The motors should remain close to equal but can be tweaked with the software. You still need some employees with mechanical skills to occasionally reset camber, toe, wheel pressure, corner weights and perform preventive maintenance like replacing wheel bearings, to keep the karts even. For racing leagues, it would not be hard to come up with a weight to power formula to allow even racing without having to put weights on the Karts (i.e. heavier people have their power set higher).
The maintenance costs could be lower. The big question is how well the batteries will hold up. How often will they have to be replaced?
The whole set up is a big investment. 60 Karts minimum. A computer control and timing system. Big screen TV. Warehouse rental.
The track seemed real busy (on a Friday night) and has been operating since 1996, so hopefully they are making money. This is some very fun EV racing. I would be here often if it was located in Miami!