June / July 2006

Sled-Edge one hour speed record attempt
The Australian Sled-Edge speed bike team made plans for their first attempt at the now expired Dempsey-MacCready Hour Record prize this month. Wet and windy weather conditions grounded their attempt but although the team are disappointed, they are determined to continue the project. The team thanks Holden for access to the Lang Lang proving ground.

Tri-Sled’s Director, Ben Goodall, has been plotting the development of a world record setting speed bike since his business was born over ten years ago. So when a local HPV enthusiast, Tim Marquardt approached him with imported molds from well-respected US speed bike designer, Matt Weaver, how could he resist?

The partnership began in early 2006, when Tri-Sled’s HPV skills were enlisted by Tim to design and construct a streamlined two-wheel recumbent to fit Matt Weaver’s Kyle Edge molds. Tim also recruited local HPV enthusiast Ken Houghton, who has a lifetime of composites experience which has been invaluable for the project’s development.

The initial start-up project involved the construction of a low-tech speed bike to fit the molds. “Whoops”, as Tim named it, was completed in May 2006 and proved to be a very solid and stable machine, with novice HPV riders able to ride it with ease. Tim’s account of the construction of Whoops can be found here.

Full of confidence and enthusiasm, the team was keen to get serious. The US$25,000 Dempsey–MacCready Hour Record prize was the perfect motivator. The prize, which expired at the end of June 2006, rewarded the first single-rider to equal or surpass 90 kilometers (55.924 miles) in just one hour.

There was very little time to waste. Tim managed to secure limited access to the Holden Lang Lang proving ground which was the perfect venue for an attempt. Ben contacted the Tri-Sled racing team and recruited Scott Hawke as an assistant technician and Jeff Neilson as “the engine” with the full support of his wife Sharna.

The team used Whoops and a Tri-Sled Sorcerer for training and testing to prepare Jeff to ride what would be a far more advanced and challenging machine.

Meanwhile, Ben began channelling his 10 years of HPV research, design and construction experience to develop the new speed bike, known as “Sled-Edge”. As with Whoops, Ken and Tim were called on to assist with laying up the shell, which this time was made of carbon/klegcell to ensure a more solid and crash resistant finish.

However, unlike the true-form molds used for Whoops, Ben decided that a few “nip-n-tucks” were needed to reduce the frontal area for the Sled-Edge speed bike and gain a little more speed. In total he took 60mm out of the height and 20mm out of the width to get Jeff extra snug inside the fairing. Ben also designed and constructed a custom drive system and crank set into a Chromoly chassis to allow for the even tighter fit.

During the first test session at the proving ground, the Sled-Edge was configured into a camera bike. Ben’s aerodynamically designed pod on top of the bike contained a video camera and Jeff had a small screen in the bike to see the road ahead. This proved to be the most testing session for the Sled-Edge team. With the low winter sun affecting Jeff’s vision and the lack of time available to get used to camera steering, they realised we were going to have to rethink video vision for the initial attempt.

After consulting with the team, Ben decided that the only workable option with minimum impact to the speed would be to add a windscreen to the bike. Although this resulted in some added aerodynamic drag, it was a necessary move to allow Jeff to get his full power down.

Further thinking and testing lead the team to decide that a combination of a smaller windscreen and camera in the nose would be the best way to get the most out of the bike with the limited time available. With only a few days to go before the attempt, Ben rebuilt the Sled-Edge and finished the bike with a shiny silver paint job.

Following four weeks of hard work and development, bad luck with the weather kept the Sled-Edge grounded on the designated day of the trial. Holden were only able to grant the team one day at the track within the time deadline and the conditions were not safe or suitable to run.

Ironically, the teams attempting the same record on the other side of the world in Arizona were having the opposite problem. Scorching temperatures meant that none of the teams in the US achieved the 90km needed to claim the full prize. As no team has been able to reach the target, the cash has been divided up to the top three teams.

Congratulations to veteran HPV rider Freddy Markham. Despite the heat he managed to set a new world record of 85.991 km on one of the last days of the trial! For more information on the Arizona speed attempts click here.

The Sled-Edge team will now wait for better weather and further access to the Holden track to put down their initial run. Ben believes that the data collected from the development and testing of Sled-Edge will put him in good stead to build an even faster model later in the year.

Thanks to Scott and Moz for the above images.