2004:  In 2004 the University of Wisconsin-Madison team introduced the Bucky 800 HD, first ever gasoline-electric hybrid snowmobile.  It utilized a 784 cc four stroke Polaris engine coupled with a 50 volt hybrid electric power train.  This power train used an Etek electric motor, Johnson Controls spiral wound batteries, and SevCon motor controller.  To help control emissions, the snowmobile used closed loop control, 3-way platinum/rhodium catalyst, and secondary air injection.  The team also took measures to drastically reduce sound emissions.  This included a side skirt, specially developed sound barriers, a two-stage tuned muffler, and passive head insulation.  

2005:  In 2005, the team utilized the same hybrid design as last years sled in a 2003 Polaris Frontier chassis.  One of the major modifications was to the control strategy for the electric motor which increased power by 25% during acceleration and charged the battery during steady state.  Other major changes to this years design was the exhaust system.  Introduced to the system was dual three-way catalyst which reduced NOx, CO, and HC emissions by up to 94% from stock.  The muffler was also redesigned to further reduce noise and the closed loop fuel injection was further optimized to run at stoichiometric combustion.

2006:  The 2006 team decided to keep the Frontier chassis and upgrade the engine to a Weber 750 cc four stroke to create the Bucky Classic 750.  The engine is also used in the Polaris FS Classic and takes advantage of closed loop control to meet the Environmental Protection Agency’s (EPA) best available technology (BAT) requirements.  To further improve emissions, the Madison crew put in dual three way platinum catalyst.  They also fabricated a custom muffler and installed sound insulation in the engine bay to reduce noise.  Since custom engine mounts needed to be made, the team was able to optimize engine placement to improve overall handling of the sled.  A custom made air intake further reduced noise and increased performance of the engine.  Finally, tunnel stiffeners, a drive paddle dampening system, and a Camoplast Silent track reduced noise output from the rear end of the sled.

2007:  The Bucky Classic was transformed for 2007 through several major overhauls.  While the team used the same engine and chassis, the way they operated changed dramatically.  The team retrofitted a Mototron control system to the engine to optimize it to run on an E85 blended fuel (85% ethanol, 15% gasoline).  The E85 system helps to reduce emissions, improver performance, and reduce dependency on gasoline.  The team worked with W.C Heraeus GmbH to create four custom made three-way catalyst to specifically reduce emissions from the Weber engine running on E85 fuel.  A two stage muffler was designed using a stock Artic Cat T660 muffler in conjunction with a custom made high frequency diffuser to reduce sound output to 73 dB.  The team designed a custom headlight system that required only 6 watts to run, reducing the required power by 91 watts from stock.  Finally, performance and handling were improved by installing a pair of Timersled trailing arms.  These trailing arms reduced overall weight by 12 pounds and increased the steering angle by 10 degrees.

2008:  In 2008, the Madison team will be competing with two snowmobiles, the Bucky 750 FX and the zero emission “Silent Buck-EV”.  The Bucky 750 FX continues to run on the 2003 Frontier chassis with the Weber 750 engine.  New for this year, the team is working on making the machine flex fuel capable.  This will allow the snowmobile to run on different fuels ranging from E10 to E85.  The are also planning on optimizing the system to run closed loop with electronic throttle control.  The team is also working on further sound, emission, performance, and handling improvements.  The Silent Buck-EV is the teams first attempt at a zero emission plug in electric snowmobile.  The design will get power from a 110 kW electric motor and Lithium Ion (L-ION) batteries.  The motor will be controlled by an Azure DMOC445 78 kW controller.  The power will be put to the track through a custom made direct drive gear reduction system.