• 1st January 2005 - By greg

    THE IDEAL CROSS COUNTRY HUMAN POWERED VEHICLE

    Here is a list of what I think the ideal cross country, potentially speed record setting human powered vehicle should be:

    1. 40 pounds maximum weight. There are plenty of hills and mountains and the lighter the better. Ideally, I would love for this vehicle to weigh no more than 30 pounds.

    2. It should have two wheels to fit into narrow shoulders and between the rumble strips and the edge of the road. Also two wheels solve the high speed stability issues. Incidentally, I am aware of a couple who travelled across Austrailia in two custom fully faired trikes. When Stuart Andrews and Paula Mathews were asked what they would change if they had to do it again, then both admitted that they would rather do it in a two wheeled recumbent than a trike for all the same reasons I have just given.

    3. It could have a three wheel option for comfort when required and stability while climbing steep hills and/or negotiating around tight corners through cities and towns.

    4. It should feature some suspension to avoid rider fatigue and discomfort

    5. It should feature an adjustable seat (seat bottom up and down, and seat top back and fourth) to change the seat angle for variety in muscle recruitment.

    6. It should feature a minimum of side fairing profile to avoid control issues in cross winds – either that or an airfoil profile from the side that helps direct cross winds over and around the vehicle.

    7. The fairing should feature plenty of easily removable surface areas to aid in rider cooling when and if conditions allow.

    8. It should be very aerodynamically efficient – ideally a CdA of .6 or better.

    9. It should feature highly luminous lighting at the rear for visibility in traffic.

    Possible candidates:

    1. Low racer with a tail box.


    (This is Jim Scozzava’s Optima Baron with carbon tailbox – I hope he doesn’t mind me using his photo)

    A good carbon low racer with a tail fairing would weigh no more than 30 pounds – in fact, I know of some that weigh-in at around 20! They are very stable at high speeds, feature a minimum of fairing area to aid in cooling and avoidance of wind turbulence and are narrow enough to fit into shoulders of any width. Typically, commercially available lowracers do not feature adjustable seats, but a custom model very easily could. The draw-back to a tail boxed lowracer is less aerodynamic efficiency than a fully faired vehicle. The CdA of a good lowracer with a tailbox is around 1.58. That equates to about 37 kph at 150 watts on flat ground which incidentally is 1 kph slower than the fully faired Rocket.

    2. Lighting recumbent with body sock.

    This was the vehicle of choice for the 2004 Race Across America HPV team and the current record holder for a human powered cross America team effort (5 days, 1 hour!!!!). If it was good enough for two trans America records, then perhaps it’s good enough for a cross Canada record. These bikes are very comfortable, feature a removable soft spandex fairing cover, and weigh in at less than 30 pounds. I would suggest the only draw back is less aerodynamic efficiency (can’t find any references to the actual CdA value) than a full fairing and that I personally think they look funny.

    3. Zote foam streamliner

    This is John Tetz’s semi-hard shell Zote foam streamliner. It weighs only 33 pounds and features an AWESOME CdA of .6 which equates to 46 kph at 150 watts!!!). It could also feature more removable fairing sections for rider cooling, and wind gust avoidance.

    4. Custom carbon faired streamliner

    This is a rough concept that takes advantage of the best of all the possible vehicle candidates and incorporates as many of my prerequisites as possible.

    A FWD two wheeled lowracer – possibly made from Zote foam to keep it light.

    Removable top to simulate a lowracer with a tailbox, but with a nose cone also. There is still plenty of fairing surface area for the wind to blow around, so perhaps the nose cone could be removable also.

    The vehicle could feature retractable trike wheels for slow speed manouvering, hill climbing or parking. These rear wheels could be very small because rolling resistance isn’t as much of a concern for manouvering speeds.

    This shows a couple of options as to how the removable top could be stowed. Another option could be a soft removable top made from Spandex like the body sock, or a plastic like Zote foam or lexan that could be rolled up.

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