Tonight on Equator HDTV (Dish Network,) the premier episode of the series “Green Wheels” will be the KillaCycle Team at Firebird raceway. See us set a new record. Learn all the technical details of the KillaCycle. Perhaps they will show the KillaCycle breaking a dyno at Faster Motorsports.
We learn something new with every race. We made a bunch of spot-on modifications recently that made a huge difference in our performance for our latest runs down the strip at the All Harley Drag Racing Association (AHDRA) event on March 30th through April 1st. We vaporized all the existing EV drag racing records with a series of quicker and quicker record-breaking runs. On the last run of the event, we clocked 8.168 seconds at 155.78 MPH.
>>> More Batteries! < <<<
We put in another 110 of the most powerful Li-Ion cells in the world to make a total of 990 A123Systems M1 cells in the bike. This pushed the power output to over 350 HP. We are now able to draw 1575 amps from the 375 volt, 7.5 kW-hr battery pack. There are just 161 lbs of cells in this pack. We call the A123Systems battery pack “Mister Fusion” because it acts like a bottomless pit of power and energy on the track. We could make 7 or 8 runs without recharging if we wanted. It only takes a few minutes to recharge the pack between runs, so we top it off every time. With the latest PFC-50 charger from Manzanita Micro, we can recharge the bike in just 5 minutes! We only use about 700 w-hrs (about $0.10) of electricity for each round. This includes the burn-out and the more than 2 mile round trip back to the pits!
Without these powerful A123Systems batteries, we would have no hope of setting new world records.
>>> Series/Parallel Shifting< <<
Another change we made was to install a series/parallel contactor. The Zilla Controller has the ability to operate a serie/parallel motor contactor automatically. The motors are inititally configured in series. Thus, the full contoller output current travels through both motors. This gives maximum starting torque. As the motors spin up, the voltage across each of them increases. When that voltage matches the battery voltage, the current will decrease as motor rpm continues to increase. The Zilla will then switch the motors into parallel connection. This will double to voltage available to each motor, but will divide the current. The motors can turn much faster, but with half the torque. It result is just like shifting a transmission from low to high.
We could not get the contactor to shift automatically during the two runs we had on Friday test and tune session. The 60 ft times were fantastic, (1.169 seconds) but we were not getting the top-end performance we needed. We re-wired the launch button to be a manual shift button and this proved to work quite well for the rest of the weekend. We plan to upgrade the Zilla firmware and we believe this will solve the auto-shift problem.
These fantastic 60 ft times translate to a 0 to 60 mph time of 1.04 seconds.
>>> Pack Heaters < <<<
Another improvement we made was to build in Kapton heaters into the battery pack. We used these to bring the pack up to optimum temperature, (75 Celsius) and maintain it there for maximum power output. The A123Systems cells are unique in that you can bring them to very high temperatures without damage. (They age a bit more quickly at high temperature, but that is it.)
>>>> Next Event < <<<
We will be displaying the KillaCycle at the Wired Magazine NextFest on September 13th – 16th in Los Angeles
The KillaCycle team (me, Scotty Pollacheck, Steve Ciciora, Derek Barger, and Scot Colburn) just got back from the All Harley Drag Racing Association (AHDRA) event at Las Vegas. I believe that the KillaCycle was the very first non-Harley motorcycle ever to participate in the Las Vegas AHDRA event, ever. Quite an honor.
The reception was warm, but the weather was a bit chilly at times. This made it difficult to get all 880 of the A123Systems lithium ion cells up to the toasty temperature where they deliver the most HP. During the course of the event, we progressively posted better times as we figured out ways of warming up the pack. On Saturday morning, we ran a restrained 10.19 @130 mph just to shake down the bike and cycle the pack. (900 pack amps, 374 volts.) Neither the fans or the tower announcer were expecting a nearly silent drag bike, so there were a lot of puzzled looks and “What the heck was THAT!” comments after the run.
This event is the AHDRA season finale, so there were a LOT of bikes running. (Great track prep by AHDRA, by the way.) We were very lucky to get three runs in all day. (10.19, 9.217 and 9.346) The runs were many hours apart, so we couldn’t get the A123 Systems pack temperature up to the desired 70 degrees Celsius for maximum power. (Other brands of Li-Ion cells would be ablaze at this temperature, by the way.) We knew we had to figure out a new strategy for Sunday.
By the end of Saturday, all the Harley fans knew who we were and were universally positive about the bike. We had a parade of tattooed bikers patting us on the back and telling us how much they liked the KillaCycle.
Scotty worked with the AHDRA officials and scheduled our Sunday exhibition runs for the afternoon. We ran the bike in the back lot several times and charged it up several times in the late morning to pre-heat the pack. We turned the Zilla up to 1350 amps, knowing the hot pack would be able to dish it out.
We ran a bit later than originally planned, so the pack was just a bit cooler than we would have liked for the first run. We set a new record on this run, however, of 9.035 @142.79 mph! (Our old record was 9.156) We quickly returned to the pits, recharged the bike, and the AHDRA folks let us run again just as soon as we were ready. The pack was up to temperature and we were able to back up our new record, making it official.
This last run was near the end of the event and it was quite dark by then. The crowd was all ready for us and cheered Scotty as he did a truly awesome burn-out. (We will post the video shortly on You-Tube.) He then rolled out of the water box and up to the staging lights, taking his time, letting the pack recover from the burn-out discharge. He launched hard and we all knew this run was going to be even better than the previous one. Just as Scotty crossed the finish line, the rear motor splashed plasma onto the track, creating an awesome fireworks display. (You MUST see the video.)