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Engineering TV also did a video on Shawn Lawless' bike |
Rocket, an electric dragster, zoomed into the record books by setting a drag-racing record speed, screaming through the quarter mile in 6.9 sec and hitting 201.37mph. The epic run not only set the record for electric motorcycles, it set the record for all electric vehicles.
The bike belongs to Shawn Lawless, president of Lawless Industries in Poland, Ohio. The company got its start building custom electrically powered transport vehicles. Now it specializes in electric floats and display vehicles used mainly at theme parks like Disneyland and Universal Studios. So getting involved with an electric dragster wasn’t too far removed from Lawless’ speciality. But building the electric dragster was truly a team effort.
Lawless devised the drive and control system. “The 13-in. General Electric motor is probably from the 1960s or 70s and originally came out of an industrial lift truck,” says Lawless. The 29-hp motor was rebuilt by Dennis Berube, a fellow racing enthusiast who runs a welding repair shop in Arizona. He turned the integral-horsepower induction motor into a lightened, high-voltage racing powerplant that typically puts out 800 hp during a quarter-mile run.
The motor is controlled by a one-of-a-kind Zilla motion controller from Manzanita Micro Power Systems, Kingston, Wash. It can handle 4,000 A and 400V, and stores 40 A-hr. The motor drives the back wheel through a relatively simple chain drive. There is no gearbox, so the driver needn’t worry about shifting. He can concentrate on just holding on, no mean feat on a bike hitting 200mph.
Juice comes from a 250-lb, 355-V lithium battery pack custom built by Derek Barger at High Tech Systems, Aurora, Colo. It’s the third and most-powerful battery pack the dragster has carried. It holds up to 14.2 kW-hr of power and 40 A-hr of charge, and the bike needs all of it for each 7-sec run.
The lithium/nanophosphate battery consists of 1,980 individual cells linked together. It requires no cooling before or during racing runs. To get those cells, Barger traveled to China and talked to battery firms to see what was available and what they could manufacture. He found a company willing to custom make cells to Barger’s specifications, and that company now supplies all of Rocket’s battery cells. Still, each cell gets checked for impedance and self-discharge, and each connection measured to ensure its resistance is sufficiently low.
A recharge is needed prior to each run and it now takes about 20 min for a full recharge using a custom charger built by Manzanita Micro that has a peak output of 75 A at 450 V. At one time, recharging was limited by the team’s power source, a generator. But the charger has been modified to accept a dc bus and the Rocket technicians plug it into a large, trailermounted battery pack, which lets them take full advantage of the charger’s capability.
Mechanics at Orange County Choppers in Newburgh, N.Y., from the cable television show of the same name, designed and built the entire chassis. But they got some help from Larry “Spiderman” McBride and his brother Steve. The two have been racing supercharged, nitro-burning motorcycles for over 30 years. Lawless says their know-how and experience was crucial in fielding the electric drag bike. Larry was also the driver on the record-setting run.
The bike runs on special tires. In front, a Michelin Pilot slick made for drag racing wraps around a 6-lb carbon wheel. The wheel was designed and built by technicians at BST Wheels in South Africa. The company uses manufacturing processes pioneered in the aerospace industry. Its racing wheels are made in a single molding operation, resulting in wheels that are stronger and much lighter than any aluminum or magnesium wheels. The hollow-spoked wheels also have their weight concentrated in the hub. This reduces inertia, which results in quicker acceleration and braking.
The rear wheel was another design effort by Orange County Choppers. It was built by RC Components, Bowling Green, Ky. It carries a wide Mickey Thompson drag slick designed by Larry McBride.
The bike has traditional hydraulic brakes front and rear, but they’re equipped with special Jay Brake pads that can handle the stresses of stopping a 1,080-lb bike going over 200 mph. Despite the high top-end speed, there is no parachute.
The biggest hurdles enroute to setting the speed record, according to Lawless, were those imposed by a TV crew eager to film the event.
“Designing, building, testing, and breaking the record within the time constraints of the TV crew was the biggest challenge. But everyone worked overtime to make sure we got it done. Failure was not an option,” he says.
Lawless and his team are still working to improve their motorcycle. “There is still room for improvement with the batteries,” he says. “Newer cells are becoming available and they should let us shave 50 to 100 pounds from the bike. We’ll also lighten the front end and replace our conventional bearings with ceramic versions. Ultimately the chassis will be rebuilt with stronger, lighter materials. The goal is to make the bike the quickest drag bike, regardless of its powerplant.”